1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.

    Dismiss Notice

Aune B1

Rating:
4.34211/5,
Tags:
  1. cleg
    Portable amplifier with unusual interior and exterior
    Written by cleg
    Published Feb 14, 2015
    4.5/5,
    Pros - nice stylish look, leather inserts, class A discrete output stage, current switching
    Cons - none for the price
    Aune is the company with their own, unique approach to audio gear. Their products are unusual and offers interesting features, absent in competing solutions.

    Their new headphone amplifier B1 looks like no other, and differs from other by its schematic. It utilises class A output stage built with discrete elements, and offers possibility to chose amplifier's current: 20 mA or 40 mA. Aune created nice page, describing B1 unique ideas, so I will not repeat them.

    First of all, specs.

    • Frequency range: 10 Hz – 20 KHz ± 0,15 dB
    • THD+N: <0,0008% @ 1 KHz, 600Ω
    • Signal/noise ratio: >124 dB @ 600Ω
    • Channel separation: > 110 дБ @ 1 КГц, 600Ω
    • Output power: 25 mW @ 16Ω, 50 mW @ 32Ω, 100 mW @ 300Ω
    • Headphone impedance: 16Ω — 300Ω
    • Battery: 4000 mA/h
    • Life time: 10 hours for 20 mA, 5 hours for 40 mA
    • Size: 65 mm × 110 mm × 18 mm
    • Weight: 230 g

    So, by size it's a little bit smaller than Fiio E12, but somewhat thicker.

    B1 is sold in small box from black cardboard with silver print. It's similar with others Aune products and looks pretty stylish for $200 device. Besides amplifier you'll get small 3.5 mm cable and Micro USB cable for charging.

    Aune B1 exterior is very stylish. It's built from solid aluminium, back panel have leather inserts on it. This protects devices from scratching, if you'll decide to make a stack with your smartphone or player. There are two color options available: black case with black leather and silver case with red inserts. Both look really cool.

    On front panel designers placed transparent windows that allow you to see main feature of B1: discrete triodes output stage, working in class A. Really nice touch, like in swiss watch you can see device's complex interior. When B1 is turned on, two green LEDs are lightened inside. Not sure, if they are necessary, but they look great.

    Major part of controls are located on left panel: power switch, gain switch and amplifier current selector (it's labeled "Class A").

    On bottom, located charging micro USB, on top — volume control and input-output sockets. On right side there is button and LED, indicating remaining charge. Press button and count LED's flashes: 5 is 100% charge, 4 is 80% and so on.

    Of course, the most interesting thing for amplifier is sound. And B1's sound is unusual. It's not as powerful as OpAmps solutions, but it still got enough power to drive almost all headphones with ease. It has almost black background, I didn't got any noise with all headphones I've tried. Discrete output stage allows B1 deliver really great amount of details, still remaining musical and pleasant sounding. B1 tries not to add anything to source's sound to preserve its natural form. Thus, if you need amplifier, boosting amount of bass, it's not B1. B1 adds more control and texture, but not amount.

    Mids are lively and transparent. You'll get all emotions, present in record. Highs are detailed and delivered with confidence, but if your headphones/source are bright, you can get too much treble, as B1 doesn't hide anything.

    Current switch is neat idea for power-hungry headphones. Boosting it to 40 mA reduces lifetime to 5 hours, but B1 drives headphones with mach more confidence: more tight bass, more transparent treble.

    So, Aune made really interesting amplifier with great exterior and unusual schematics, delivering great sound.

    2Box.jpg
    3Acessories.jpg
    5Rearside.jpg
    6Schematics.jpg
    9WithQLS.jpg

    I've made simple video, to showcase B1

      bala, nick n, warchild and 4 others like this.
    1. View previous replies...
    2. cleg
      @coletrain104, I've tried with lots of IEMs, and it's working great with them. Almost no noise
      cleg, Feb 24, 2015
    3. Alou
      The desin looks very interesting!
      Alou, Feb 24, 2015
    4. Henke
      I just got this little gem.
       
      Very good sound. When I'm using my IEMS, Supra 2 from Earwerkz, it quickly gets pretty loud so perhaps for very sensitive IEMs, this might not be perfect but on the other hand I cannot hear any hiss or background noise. I can hear the music very very faint when the volume is at zero, but no noise.
       
      I've also tested it with my HE-500s and I feel that it drives them pretty good. When I switch over to higher current, I notice that things gets... somehow a bit firm, drives them with a bit more authority I guess. And it can drive them pretty loud... and then I'm on low gain so there might be room for headphones that are abit more power hungry.
      Henke, Mar 2, 2015
  2. avitron142
    King in its Price Range, Phenomenal in its Features
    Written by avitron142
    Published May 26, 2015
    5.0/5,
    Pros - Class A Portable, Excellent Sound, Elegant Design, Battery, Size, Power.
    Cons - Weight, Instrument separation.
     

     

    PreIntroduction:

     

    I am in no way affiliated or work for Aune. For this review, the Aune B1 has been provided to me as a review sample by Aune, as one of the 10 review samples sent out to head-fi’ers.

     

    Keep in mind that all the pictures, while looking small on the page, were taken by a quite decent camera. I just didn't want to clutter up the page with large pictures. Feel free to click on them and open the image in a new tab to see them in full resolution throughout the review!
     

     

    Introduction:

     

    There haven’t, erhm, been too many Class A portable amplifiers on the market, so introducing this as part of a group is quite difficult. The Lear FSM-2 V2 may be one of the only other ones I’ve heard of, and even then only fleetingly, and at more than double the price point of the B1. In terms of power, though, there has been a few budget amps that pack a punch, including but not limited to the Fiio E12 we all love at its price point.

     

    So, the point? That Aune’s B1 is quite interesting before we even start, by doing something almost nobody else had the guts to do – a fully portable class A amp, for all those that don’t want to be glued to a wall outlet (anybody? Any takers? Well, me for sure). Yeah, you could go for the E12, but what if you’re past budget-fi, and want to do justice for your more power-hungry headphones, and your X5/dx90/A&K player to boot? I was recently put in that situation, where I was blessed enough to be able to get both the AKG K7XX and the Shozy Alien. So then all I needed was an amp.

     

    How hard could it be already?

     

    Hard enough. I went through 5 or so amplifiers, the E12 the only one powerful enough in my opinion to drive the K7XX to a fuller sound (none had problems with volumes, but then again, volume isn’t everything, right? Quality is the beast we’re discussing here), and couldn’t help but wonder if it was limiting the wonderful sound my other two pieces of equipment were capable of producing. So I jumped at the chance to get a B1, hoping that class A was what I was looking for, while also hoping power wasn’t the only good thing the B1 was good at.

     

    It’s good alright. Very, very good. But more of that in the review. Let’s begin!

     

    Packaging:

     

    I’m not a fan of this section in general, but while I’m at it, I am a fan of the B1’s packaging. Nice an’ simple, just the way I like it. Comes with a 3.5mm to 3.5mm cable, as well as an usb charging cable – standard, not a feared proprietary cable like Cowon’s.

     

    DSCN4694.jpg DSCN4704.jpg DSCN4711.jpg

     
    Build Quality & Design:

     

    image10.jpg Tank certified, in my opinion. Much better built than the Schiit Magni 2 Uber I’ve owned, though that wasn't too shabby either. Made almost fully out of metal, and, although I have no idea how I know this, it feels like the metal is thick as well. No hollow-ish sound I’ve had when the components didn’t exactly fit the case they were assigned to; the B1’s case feels like it was made in Germany, ja? I would be afraid of dropping it though due to the fancy see-through glass, although through my rigorous tapping tests I’ve decided it’s pretty sturdy as well. Don’t drop this though – well, make that don’t drop any of your audio equipment, unless it’s created by Apple.

     

    Speaking of the see-through screen, it gives this amp a look of authority. Man, I’m usually scared of anything see-through – it reminds me of the components inside and how they could break. But with the B1, I don’t have this problem. It’s really weird, I was expecting to treat this like a vase, but instead I’m treating it like a Swedish Volvo, carrying its own weight and build quality plenty. I’ve never seen a sturdier built amp around, even with the partial see-through screen, and that’s saying something. The symmetrical led lights the amp gives when powered on is classy to the max. My initial impression when I took this out of the box was that I could probably convince my roommates it had a built-in wine flask.

     

    The leather backing on the other side only confirmed my wine-flask theory. Soft and comfortable, this is another point for the B1’s classiness.

     

    The volume knob is the only thing that people may take up for debate. It is made out of hard plastic, not metal. Now before people start arguing that the E12 has a metal knob and thus better, I just want everyone to know that the plastic Aune used here is just fine in this case. The knob moves smoothly, and it doesn’t appear to shake or wobble no matter how hard I try. So will it stay working for 3+ years? I couldn’t tell you, but it seems well-built enough to stand the test of time, in my opinion. Although a diamond knob would have completed the classy setup, there’s only so much you can expect for $200, you know?

     

    My, they really had a wonderful designer when they made the B1; it looks like it just came out of fine dining, with no way to argue otherwise if I had even wanted to. It simply just looks really, really good all around. Sturdy and elegant, more well-designed than any other piece of equipment I ever handled. Well done, Aune, seriously. I just wish the volume knob could have been outta diamond/platinum, ‘cause that’s really the only thing that anyone could ever nitpick about.

     

    Basically, Aune did well in this department. Not only is it built like a tank, they managed to add the see-through-glass/led-lights/leatherback for a classy, well designed look.

     

    DSCN4721.jpg DSCN4723.jpg image3.jpg

     
    Buttons/Switches:

     

    I’ve already discussed the knob, so moving on one side there’s the power switch, current switch, and gain switch. On the other side there’s the power indicator 

    image5.jpg
    button. All of the first 3 seems well done, and doesn’t look like they would be switched on/off accidentally, which is what I was hoping for, especially given the fact that so many got it wrong in that regard. At the same time, though, they’re also not hard to use if you try, albeit a bit on the safer/heftier side in that regard. I’ve been furious for a while that the E12’s side buttons (gain, crossfeed, etc.) are meant to be used with a toothpick, and even when 3 inches from my nose is incredibly hard to use. Fun fact: I actually thought when I got the E12 that the buttons fell off and I was seeing the mechanics behind it. Like, yeah. So all I’m saying is I’m happy the B1’s buttons are very useable.

     

    The power indicator button works fine, and I’m glad Aune incorporated it, as it’s a brilliant way to check and see how much battery is left.

     

    As for the switches themselves, the power switch is self-explanatory, so I’ll continue with the other two. The gain switch provides a 10db or so volume boost, which works well for the K7XX, but isn’t a shocking jump, when using full-sized headphones. With IEM’s, such as the SA7, it’s a bit of a jump if you hit it by accident, but I don’t see that happening anytime soon. The current switch goes between 20MA and 40MA, although even with power-hungry headphones like the K7XX I could barely hear a difference; I think the 40MA current provides slightly more authority to the sound, although the difference is so small I’d be more than happy if I had to live with only the 20MA. The reason why I’m saying this is because the battery gets halved (more on that later) when under the higher current, and many of you are probably wondering if it does well on the “low” current as well, for more portable uses. But fear not; both sound amazing, and the 20MA doesn’t sound thin in the slightest. If I understood correctly though, both of them are class A currents, so there’s no real “low current” here, only high and higher.

     

    It is important to note that Aune strictly advises against switching the current when powered on, so many might nitpick with that. But to me, if it’s not prone to accidents, and you have the foresight to keep Aune’s warning in mind, there’s nothing to talk about.

     

    Battery:

     

    Let’s take a step back and consider what current this lion is giving us. Fully class A. Now taking that, let’s consider its battery life; 10 hours for the 20MA current and 5 for the 40MA. At first glance, this would make people recoil. But after you consider the wattage we’re getting here, it suddenly turns into a gem. 13 hours on the Oppo HA-2? No problem, we’ll get you a Schiit Asgard current in a portable package straight away.

     

    Seriously, though, if you know what we’re dealing with here, 10 hours should raise eyebrows. And especially since you probably won’t even need to use the high-current when you go outside (unless you’re using 300 ohm IEM’s,) you'll only have to worry about the ten hour battery, not the 5 hour one. I’m usually not a fan of current switches, as they’re usually an indicator that the low current is not enough, but with this I’m keeping it in low current and taking the 10 hours with me. Low current still powers my headphones like a boss. For a Class A, truly a remarkable feat.

     

    *Now, I wish Aune told us whether the 10 hours is in low gain or in high gain, but I should be able to find out soon enough. Get back to you guys later on that.

     

    Heat:

     

    Since this is a Class A, can you fry eggs on it, as with many other infamous Class A amps? (I’m talking to you, Schiit Asgard 2!)

    No, and a big relief at that. I’m happy to say that when using it all of today, the Aune B1 only gets slightly warm, never hot to the touch. A potential issue that many were worried about, Aune seems to have found a good lid for heat control on this one.

     

    Size, Weight & Portability:

     

    Size is small enough and at a good size, being exactly the same size (L x W) as the E12, while being just a tad thicker. Weight, though, is quite hefty. Obviously it’s liftable, but it may not be what you have in mind for your ultra-light setup. This is probably due to the components inside, so it’s all for good cause. Just thought I’d make a mention that this is not a featherweight amp by any means, and as a class A amp I wasn’t expecting it too. It should be great in backpacks and in inner coat pockets, but not in jacket/pants pockets, and definitely not while jogging. However, if you could get past the weight, portability is fine. Pictures:

     

    image7.jpg image8.jpg DSCN4736.jpg DSCN4739.jpg

    Note: On the left is the Fiio E12, on the right is the Aune B1.
     

    Amplification & Volume:

     

    Volume is quite plenty, especially if you keep it in high gain. As far as amplification goes, my main IEM gains massively from high gain, while with the K7XX it’s not that much of a difference. If I had to point it out, high gain gives more of an edge to things, which in turn makes it feel more refined. With my KRK KNS-8400 and the Bang & Olufsen H6, though, low gain is also quite fine, although high gain still has a *slight* edge. So it seems that the SA7 at 50 ohms is the only one who doesn’t like low gain. It does beautifully on high gain, though, so there’s nothing to worry about here. As I have said, volume is not a concern with the B1, and the B1 works fantastically with everything I’ve thrown at it.

     

    As I'll mention later on, the B1 is way ahead of the Fiio E12, especially when it comes to detail retrieval, clarity, and overall balance, all of which I will discuss in the sound section. As for the Schiit Magni 2 Uber (from memory; I haven't had the Magni in a good month or two), the Magni 2 has absolutely no viable edge to my ears when it comes to power because let's remember yet again that the B1 is a Class A amp. So besides for the fact that the B1 is powerful and portable, the B1 sounds yet better to my ears; Detail and musicality probably being its winning factors, but really the B1 -portable or not- is a step ahead of budget-tier amplifiers to me. The overall sound of the B1 is more than I could ever ask out of the Magni 2 Uber, possibly excluding the soundstage, which may or may not have been better on the Magni 2 (I can't really remember all that well now). In all other respects, though, I'd pick the B1 any day.

     

    When comparing the B1 to the Heir Audio Rendition 1 amp ($330) - by memory, it seems that the Heir wins by a small margin when paired with IEM's, as that's the only thing it's geared to do. However, the B1 is not lagging far behind, and definitely takes the cake when it comes to over-the-head headphones, whether they be closed back like the KRK's or open-back like the K7XX. It's not really a fair comparison to begin with, as there's no reason to buy a Class A amp just for IEM's. The B1 has a lot more going for it than the Rendition 1, unless your entire collection is built entirely of IEM's, like @ClieOS .

     

    Hiss:

     

    The B1 has a very black background, and there's not much hiss at all unless I strain my ears to hear it on the highest volumes with my IEM, and even then I’m not sure if I’m imagining things. So no worries for your IEM’s here.

     

    Sound:

     

    Here’s the good part of the review, it’s as good sounding as it is classy. Much of the E12, and it should be, at its price point. Much more controlled in the lower end, detailed in the highs, and overall balanced. Here’s the breakdown:

     

    Lows/Bass: Exactly where I want them, quantity and quality, like an iron arm. Doesn’t overpower my K7XX’s like some other amps do, and keeps everything quite even. I wouldn’t call this lacking in bass though, as when the song requires it to pack a punch, it does very well. Details on the low end are done very nicely, no uncontrolled bass lows on the K7XX’s anymore, which is more than I could ask for. The bass is very fast, which is the first time I’ve ever been able to pick that up on a piece of equipment, so I may be off or hearing something else there. I’d like to emphasize here that although I’m usually not quite impressed with the lows, the bass here really give definition and balance to the music.

     

    Mids/Vocals: Vocals have no complaints from my end, especially when so many have failed me there. Guitars and other instruments are at its prime here, though. I’m savoring everything from the good ol’ Sultans of Swing up to my OCRemix albums that came out last year. Chrono Cross’s OST, when I played that game at 5 years old, doesn’t fail me here either, which makes me smile. Overall, mids are a beast, and instrumentals are glory with this one.

     

    Highs/Drums: I was expecting some kind of roll-off here, as what can be perfect? But, contrary to my expectations, highs are as crisp and detailed as they come, without being bright to my opinion. Not emphasized, but with a strong presence, as they should be. I should remind everyone again that the B1 is very balanced, so it should go without saying that the highs don’t overpower anything, or even feel bright. I just came from a treble roll-off amp and my ears don’t feel fatigued at all, even after 3 hours, if that helps. The highs sure are precise, though.

     

    Coloration: None. Sound is very natural, and is as good as your source DAC/DAP, so however that’s supposed to sound you’ll get it.

     

    Tonality: A warmer sound, though at no time muddy; the B1 stays extremely detailed for its price even with its warmth. It creates a very inviting and comfortable sound that you just want to sink into, though sacrificing a big soundstage.

     

    Soundstage: Well-defined, although I do have to say it’s a tad on the smaller side, due to the B1’s warmth; but within the presentation it gives, it remains very 3D-like. I’m left satisfied, and frankly I’m fine with the way it is. Coupled with a big soundstage from the K7XX, it stays comfortably large, albeit not huge. With the KRK KNS-8400, it has no indication of being small though. So whether you want to use this with open-back headphones or closed-back ones, they’ll both sound wide enough for leg room.

     

    Imaging: Well done; whatever the soundstage may lack, the imaging more than makes up for it. The components of the song are all around you, not only front and center, and I can tell where everything’s placed.

     

    Separation: The separation would be the only non-strong point of the B1, if I had to pick one. The B1 is more of a musical amp than an analytical one. As such, components tend to blend together musically than staying completely separate where you can pick them out. However, due to the nature of the B1, this helps the amp stay musical and the music flow. This isn’t an analytical amp though, as I’ll mention soon.

     

    Frequency shape: Flat, but doesn’t have a flat-ish sound. Every part of the spectrum is lively. Does that make sense?

     

    Detail: Very detailed in highs, mids, and lows, I’m proud to say. I’m quite pleased with the amount of detail it presents overall. Detail is definitely one of the B1’s strongest points.

     

    Accuracy: It’s hard not to love the accuracy the B1 provides, especially given its detail. Sound is fast and on point to my ears, and being both very accurate and detailed just makes the B1 a deadly competitor and a king in this department.

     

    Balance: Also great; I wouldn’t have imagined that the sound sig could be the way it is without having something boosted in some way. But I have to say, the balance of this amp is near perfection, especially compared to the amps I’ve tried before. Definitely makes my K7XX and KNS-8400 sing.

     

    Coherency & Flow: A very musical amp, this is the type that makes you want to sit back on your couch and sink in. It doesn’t sound unnatural though, and doesn’t blend in together too much. It flows just right to me.

     

    Reveal Factor: The B1 is quite revealing, something that’s going to be coupled with any very detailed amp, I’m afraid. To illustrate, I was a bit shaken when I was hearing recording mistakes in my songs I had no idea existed, even with any of my other amps. However, feed it quality stuff, and it’s very rewarding.

     

    Immersion Factor: I have to mention that this isn’t a very analytical amp in the sense that it sucks you in, so don’t expect to be paying attention to every little detail, because in the end, you’re going to space out and have to rewind. That’s why reviewing this is so darn hard; I have to listen to each song 3 times until I can finally pay attention to how good it is. That’s the immersion factor to you.

     

    Sound Summary: It sings. That’s the best 2 words I can use to describe it. You won’t be analyzing your music anytime soon, as the B1 will invite you in and shut the door behind you, until you realize you’re not doing much analyzing and rewind back 3 songs later. Very musical, detailed, and 3d-like presentation, all the while keeping a steady coherency and flow that won’t leave you disappointed. The most important part of this review -the sound- the Aune B1 excels at, especially given that it’s a portable amp.

     

    Value & Conclusion:

     

    The B1 is a serious threat to other amps, even just given it’s features, which, let me remind you once more, is fully Class A in a portable package. Yet Aune didn’t stop there; the B1 excels at sound given its price range and looks wonderfully classy to boot. Quality heating control, and battery life is very decent given its specs. Size is in a great form factor, although the B1 is on the heavy side. Almost all definite positives, while having very little that there’s not to like.

     

    I would recommend this completely to those who don’t want to be glued to wall outlets while powering heavy voltage-needy headphones at home, and also want an extremely potent portable amp for their daily travel with portable/closed-back headphones. For those looking for a sole IEM amp, I’m not sure why you would look at a Class A amp to begin with, but hey, it does well with those too.

     

    All in all, the Aune B1 really packs a punch given everything it has going for it. If I had $200 to spend on a portable amp that could double for desktop headphones, I’d most certainly buy the B1 in a heartbeat. I couldn’t find anything wrong with it if I tried.

     

    -Avishai

     

    P.S. – the B1 sample I just reviewed is going on tour in a week or two; the application thread is open here http://www.head-fi.org/t/768275/aune-b1-usa-tour-application-thread for those that live in the U.S.A and want to give the B1 a try. Good luck!

     

    Video review:

     

    [​IMG]

     

    A few other Pictures (that didn't make it to the review):

     

    DSCN4696.jpg DSCN4701.jpg DSCN4708.jpg DSCN4721.jpg image1.jpg image2.jpg

    1. View previous replies...
    2. avitron142
      @miceblue Haha, I wasn't aware of that :D . Detailed measurements are not my thing, so I'm going to have to go with you on that. It'll be interesting to see how the B1 stacks up with 300/600 ohm headphones though, I'm sure some people in the upcoming tour has some HD600's or DT990's.
      avitron142, May 30, 2015
    3. miceblue
      Oh it should be juuuuust fine with those headphones. I just got my AKG K240 Monitor measured by Innerfidelity (a whopping 688 ohm impedance and requires 0.447 Vrms to reach 90 dB SPL), and the B1 can get it to 111 dB SPL. I'm using it with the B1 right now and it does a better job than with the OPPO HA-2 since the HA-2 is much more limited in voltage output. That's thumbs up for the B1 when using high-impedance headphones!
      miceblue, May 31, 2015
    4. Hi-Fi'er
      I agree with this review. The B1 is a hard act to follow. It rivals my Cypherlabs that costs way way more. I would say it's 90% there what a portable amp should be.
      Hi-Fi'er, May 6, 2016
  3. Cotnijoe
    Aune B1 Amplifier: Gorgeous Inside and Out!
    Written by Cotnijoe
    Published May 27, 2015
    4.5/5,
    Pros - Sexy Design and Build, Fantastic Sound
    Cons - Slight Channel Imbalance Issue
    Introduction:
    One of my favorite parts of this hobby that I've grown to love over the past few years is trying new things and just experiencing how different components (or combination of components) have their own unique way of expressing what is essentially the same music. So when Aune Audio began looking for reviewers of their B1 amplifier, I jumped on that train real fast. I’d like to give a big thank you to Aune Audio for providing me a unit to review and, of course, my review is solely my own opinions and I am in no way affiliated with Aune Audio.
     
    Packaging and Accessories:
                The Aune Audio B1 came well packaged in a DHL bag, a brown box, and finally its actual box. The box is sturdy and simple. Inside, you find the amp, manual, a business card, a USB cord for charging, and a short 3.5mm to 3.5mm cable. The overall presentation is simple but very nice, and Aune provides everything you may need to get the B1 up and running. The only thing that I would have liked to see is some sort of storage case, or even just a nice little bag for it.
     
    IMG_0058.jpg IMG_0059.jpg
    IMG_0060.jpg IMG_0062.jpg
    Inside of the packaging. Nice and simple!
     
    Build and Design:
                The Aune B1 is built like a tank, and it’s a damn good looking amp. Its chassis is built from brushed aluminum with only its volume knob being made of plastic. The B1 feels solid and has a nice heft to it. The build quality leave little to be desired and a whole lot to admire. My unit did come with two tiny tiny scratches, on at the bottom of the amp, and one on the volume knob that made me a little sad. Honestly though, build is awesome!
     
                It’s clear that the engineers over at Aune Audio paid a lot of attention to detail when designing the B1. The “highlight” of the B1’s design is obvious its two windows that show the components inside the amplifier. When I first saw a picture of the B1, I thought it was some sort of portable tube amp. I mean c’mon… looking at the tubes is half the fun! Now obviously the B1 isn’t a tube amp, but I still think displaying its internal components was a pretty cool little feature and is definitely a bonus in terms of aesthetics. The LED lights just make things even more awesome to look at.
     
                The buttons around the B1 are also well designed. Most of the functions of the B1 are controlled by sliding switches, where you slide it to turn a feature on or off. To prevent the switches from being easily changed, Aune had the chassis on the sides slightly indented. I don’t think that’ll solve the problem completely, but I personally had absolutely no problems with the amp accidentally shutting off or accidentally blowing my brains out by switching to high gain, so hey… what do I know, maybe it’s doing its job just fine.
     
                The back side of the B1 is well designed with two strips of material that keep the amp from sliding too much on a flat surface and prevent the amp from scratching. Now I won’t pretend to know what material it is, but I would guess that its pleather (I don’t think its real leather?). All I know is it looks very nice and gets its job done.
     
    Size wise, I think the B1 is very reasonable. It’s a little taller than my iBasso DX90 with about the same width. The two as a pair looks very nice!
     
    My only gripe about the B1’s design is that if you decide to make a portable stack by rubberbanding a DAP to it, it’ll block off the gorgeous display of its components unless you use the other side. But then that defeats the purpose of the pleathery material protecting the amp and you risk scratching the amp. Oh well… it seems inevitable.
     
    Again though – Built like a tank and damn good looking.
     
    IMG_0061.jpg
    Sick!              
     
    Features:
                The B1 is quite a special little device. Not only is it a class A portable amp, which is not all that common, it also has an interesting current switch that gives it a bit more flexibility in driving more demanding headphones. In addition to that, the B1 also includes an on/off switch, micro USB charging port, battery indicator, and of course a volume knob, input jack, and headphone out jack.
     
    Being a class A amp, the B1 does get quite warm after using it for some time. It remains very safe to touch though and never gets overly hot by any means – definitely still very safe to keep in your pocket or to use portably.
     
    What’s kinda bizzare is the current switch. In the B1 manual, Aune quotes in RED, “Never flip [the current switch] under B1 is working.” Ignoring the slightly broken English, it doesn’t sound like Aune is messing around. I wonder what would happen if I just … …
     
    Battery Life:
                The B1 is advertised to be able to run for 10 hours with low current and 5 hours with high current. I did run the battery dry on low current and got approximately 9 or 10 hours out of it. I didn’t keep a strict count, but the battery life is certainly around what it’s advertising to be. 10 hours isn’t bad, but it is trumped by other portable amps that can last 20, 40, or more hours (The most I’ve heard of is like 80 hours or something. That’s pretty insane.). However, remembering that most high quality audiophile DAPs currently on the market can barely last 10 hours, it’s not a problem at all. You’ll just have to remember to bring two chargers along when going on a long trip! Plus, remember that it’s a class A amp and, thus, fairly inefficient, I guess 10 hours is actually pretty good.
               
                I didn’t bother running the B1 on high current to see how long it lasts, as I don’t see that as necessary. If I’m running it with high current, I’ll probably be using a fairly demanding headphone, which means it’s not portable and I’ll probably be near some sort of power source where I can freely charge up my B1.
     
    Sound
                       Listening was done with my iBasso DX90 as the source running line out into the B1 and then into my Earwerkz Supra 2, HIFIMAN HE560, and HIFIMAN HE1000 (just for fun and cuz I have it with me as a beta unit… why not). Basically all genres are covered and all audio files ranging from 256kbps and up (with the exception of DSD files) are used for my sound impressions.
     
    FullSizeRender2.jpg IMG_0067.jpg
    iBasso DX90 > Aune B1 > Earwerkz Supra 2 using plusSound Cables.
     
    Noise Floor
    The B1 is quiet. With my Earwerkz Supra 2, one of the most sensitive I know, it does have a tiny bit of hiss, but a VERY manageable and hardly noticeable amount. It is one of the quietest amps I’ve had the pleasure of listening to and I wouldn’t worry about it hissing at all honestly – very nice and very dark background. The DX90’s amp section still trumps it in terms of noise floor, but it’s hardly a difference at this point.
     
    Channel Imbalance
    The B1 does have a bit of channel imbalance issue that could be problematic, as the B1 also happens to be pretty loud. Running DX90 > Aune B1 > Earwerkz Supra 2, I had to set the line out volume of the DX90 to 200/255, which is the lowest I’ve ever had to set it, in order overcome the regions on the volume knob where the B1 has its channel imbalance. So what does that mean? Well first off, those using the most sensitive IEMs may need to do a bit more research or to give the B1 a listen first to make sure that the B1 is a good match with the sensitive IEM. And second off, those that do not have digital control over their line out signal may also need to do more research. It’s really unfortunate to see that this may be the dealbreaking point for those using the most sensitive of IEMs because of the sound that the B1 produces (hint: it’s awesome).
     
    Sound (For Real Now)
                As a whole, I think the B1 is one of the most neutral portable amps that I’ve ever heard, and is certainly the flattest sounding in the sub-300 dollar range that I know of. And that’s a good thing. I really like this neutrality that the B1 has.
     
    B1 compared to Amp section of DX90 (Using Earwerkz Supra 2)
                I love my DX90 and I consider it to be one of the best (if not the best) DAP currently available under 500 dollars. I do have a few gripes about it though, as I feel that it is just a bit warmer and smoother sounding than I would prefer it to be. The B1 addresses that issue for me quite beautifully. When connected to the DX90 via its line out, the improvement over using just the DX90 alone is significant.
     
                The most obvious change and improvement come in the bass department. The B1 removes the midbass bump that I find the DX90 to have, and bring on better bass extension. What you get is a much cleaner, tighter, and faster bass that retains a very fun sound all while making the sound straight out of the DX90 seem muddy and bloated in comparison.
     
                The midrange of the current firmware I’m using on the DX90 (FW 2.2.0) was a little forward and can be just a bit thin and unnatural sounding for me. The B1 also helps the DX90 out here. It pulls the forwardness back just a tiny bit while giving the midrange more fullness by presenting a flatter upper midrange that fixes the DX90’s slightly unnatural tone.
     
               The treble from the B1 extends better than that of the amp from the DX90, giving the sound slightly more air. The B1 also adds a nice crispness to the sound, but never making the sound harsh or bright.
     
                The other major improvement that comes with the B1 is the soundstage and separation. You get a significantly larger soundstage, particularly in width, which really opens the sound up. Separation is also a very big step up compared to listening with just the DX90. The sound from the DX90 alone is claustrophobic and congested in comparison to the very nice and open sound when you add the B1 into the picture.
     
                After spending some time with the DX90 connected to the Aune B1, it’s honestly very hard to go back to listening with just the DX90 as the B1 just tightens and cleans up the sound so fantastically well. This is not to discredit the DX90 of course. It’s a 400 dollar all-in-one box solution with everything stuffed into a very small box. On the other hand, the B1 is 200 dollar standalone amp that’s bigger than the DX90. Hell it better be better than the amp section of the DX90. What is awesome, however, is just how much better it is. The B1 really is a fantastic sounding amp and if you’re willing to sacrifice some portability, it is very well worth the additional 200 dollars and extra bulkiness. This thing simply sounds fantastic.
     
    DX90 > B1 > HE560/HE1000
                This portable combo drives the HIFIMAN headphones quite admirably if I must say, and in the event that I’m traveling and staying at a hotel or something where I can use my full size headphones but obviously couldn’t bring along my full size amplifier, I would be happy to live with this combo for the time being.
     
                Some things that it tends to lack while driving these headphones in comparison to my Asus Essence III:
     
    -The bass extension and punch is good, but it does lack the last bit of bass extension that gives the rumble that planar magnetics are so famous for
     
    -Overall soundstage is a bit smaller but holds its own. The B1 tends to lack a bit of depth, and that really comes out when paired with the HE1000. The HE1000 is a fantastically layered headphone with great out-of-head imaging, and it clearly doesn’t perform its best in terms of soundstage and layering when paired with this combo.
     
    -Not surprisingly, the detail retrieval of this portable set up is not on par with the much more expensive Essence III, but for the price, it does a very respectable job.
     
                So I also tried listening to the HIFIMAN headphones with different current settings, and honestly I don’t hear all that much a difference. The HE560 and HE1000 are not notoriously hard to drive. If anything, they’re some of the easiest orthodynamics on the market. I would guess that perhaps the current switch would make more significant of a difference on headphones that are more difficult to drive. I would swear that the HE1000’s treble is just a teeny tiny bit sharper when the current is set to high, but I would really not bet my money on it. For me, the difference between the two settings was pretty much nonexistent.
     
    Summary on Sound
                What you get from the Aune B1 is an impressively detailed sound that is very well balanced and gives a great sense of space. I wouldn’t be inclined to call this amp warm nor cold. To me, it’s simply pleasantly balanced and uncolored. Despite that, the B1 is in no way boring to me as it has a very tight, crisp, and detailed sound that just begs you to take notice of it. I’m very happy with what the B1 offers and I think it is of fantastic value at its MSRP of 200 dollars.
     
    Final Thoughts:
                Aune Audio was a company that I was aware of, but never paid all that much attention to. I know they made some well-regarded desktop friendly components, and I thought their company logo was pretty slick looking, but that’s about it. My experience with their B1 amplifier really put them on my radar. I obviously hold the B1 in very high regard, and I think it’s a gorgeous piece of gear – inside and out. I would like to thank Aune again for the opportunity to demo this beautiful portable amplifier, and I’ve very excited to see what products they have planned for the future!
                Do I recommend this product? Absolutely yes. The only thing keeping me from giving the B1 a full 5/5 is its channel imbalance issue. If Aune is able to resolve that issue somehow, I think this amp would be an easy recommendation to just about anyone looking for a portable amplifier at this price. But for now, those using a DAC with a powerful line out signal combined with a sensitive IEM may want to think twice about purchasing this amp. For anyone else, go crazy! 
      thelonious58 likes this.
    1. avitron142
      Nice review! Our reviews seem to agree on most parts of the sound department, with the exception of the soundstage and separation. Are you sure you could pick out the instruments from the crowd? Mine seem to blend in musically so it was hard to do so, IMO.
      avitron142, May 27, 2015
    2. Cotnijoe
      It could very much be a pairing issue for you. I have no idea. I did find the soundstage to lack a bit in layering and depth, but besides that the sound is crisp and clear especially with my in ears.
      Cotnijoe, May 27, 2015
  4. Loquah
    Aune B1 - a surprisingly versatile headphone amp
    Written by Loquah
    Published May 31, 2015
    4.5/5,
    Pros - Spacious, nuanced and textured sound, versatile with a range headphones, elegant design, well priced
    Cons - Too powerful for IEMs, may have output impedance high enough to alter the sound of balanced armature IEMs
    I received the Aune B1 for this review direct from Aune at no cost to me and may be given it for free or will be able to purchase it at a reduced price as part of the terms of the agreement Aune made with the 10 reviewers selected. Either way, the chance to get things for free doesn't influence my reviews - if it's no good, I wouldn't want it anyway and if it's good, I'll gladly say that regardless of the possible gain.
     

    Overview

     
    Based on their products thus far (like the S16, T1, and M1), Aune seem focussed on making affordable products with high performance. Sometimes that works extremely well, like the T1 DAC, and other times it backfires a bit, like the S16 with its slightly sub-par amplifier stage and M1 with its high output impedance and WAV-only design. Both of the misses have shown outstanding potential and the hit (the T1) was a real hit, so where will the B1 be placed in history?
     
    At around $250 (AUD) it's priced in the upper range of affordable portable headphone amps amongst some stiff competition so it's not necessarily trying to undercut the competition in price and that means it has to outperform them somehow to be really appealing. Let's see what it's packing to help with that challenge.
     

    Specifications

     
    1. Up to 10 hours playback
    2. Suitable headphone impedance:  16-300 ohm
    3. Size:  65 x 110 x 18 mm
    4. Weight:  230g
    5. THD:  < 0.0008% @ 1kHz
    6. SNR:  > 124dBA
    7. Frequency response:  +/- 0.15dB between 10 Hz - 20,000 Hz
    8. Crosstalk:  < 110dB @ 1kHz
    9. Power (class A mode): 25mW/16ohm, 500mW/32ohm, 100mW/300ohm
     
    So, on paper the B1 packs plenty of solid specs including low distortion (THD), good channel separation (crosstalk), and decent power. Let's divert our attention from the specs and the sound to the look and feel of the amp and then we'll circle back around to talk about the all important sound quality.
     

    Design & Functionality

    Size & Weight

     
    The B1 is designed with the fairly typical footprint of most portable amps and that's a good thing because it will stack well with the many and varied DAPs on the market. That said, it's a bit bigger and heavier than some of the alternatives. For example, compared to FiiO's E12 family (E12, E12DIY, and E12A), the B1 has the same chassis width and length, but is about 4mm thicker. It also weighs about 70g more which doesn't sound like much, but for some people it can start to add up if you've got a heavier DAP.
     

    Knobs and Switches

     
    AuneB1-0250.jpg The B1 is concisely laid out with all switches up one side, input, output and volume on one end, a micro USB socket for charging at the other end, and a battery level button on the remaining side. The result is elegant simplicity in terms of the B1's appearance.
     
    The battery level button triggers a simple system of LED flashes to show battery level from 1 flash (charging needed) to 5 flashes (battery full). Just like the overall design, this approach is simple and elegant.
     
    There's not much to say about the volume knob other than it is an interesting flanged shape, but is easy to hold and turn. It appears to be plastic, but it doesn't look out of place or tacky on the black B1. I'm not sure how the aluminium design fairs with the volume knob.
     
    The inputs are well spaced and slightly recessed with an attractive inward curve from the surrounding metal housing. I was worried that the slight recess might play havoc with some plugs, but have had no problems with the connectors that are most prone to these problems so I don't think that design choice will have any negative impacts and it looks really nice so I'm glad they did it.
     
    On the action side of the amp are the three most interesting switches. The switches are all made of plastic, but that's a good thing I believe. The pre-production B1 I played with had aluminium switches and they felt rough to touch because of the slightly sharp edges caused by the machining. It's possible that Aune could have made smoother aluminium switches for this final production version of the B1, but I'm quite happy with the black plastic. It looks and feels like good quality plastic and is a much smoother and more comfortable user experience than the pre-production version.
     

    The Mode Switch

     
    The mode switch is labelled "Class A" because it changes the current output of the amplifier by changing to A-class operation. I don't claim to be an electronics expert so I'm not going to attempt to explain A-class operation in detail, but suffice to say that the reasoning behind A-class operation is that you can sacrifice power efficiency (i.e. battery life) to reap benefits in sound quality and that's what this switch is about.
     
    Aune clearly instruct users to always switch the amplifier off prior to changing modes so direct comparison of the differences in sound are hard to complete without 2 amps side-by-side, but my rapid switching (power off, wait for the click of the relays, change mode, power on) between modes resulted in some subtle differences to sound that were mostly headphone dependent. Some cans prefer A Class while others prefer the normal mode from the B1 it seems. As you'll read later, I'm a fan of this switch and you might be too. It's not just a gimmick.
     

    Aesthetics & Finish

     
    AuneB1-0254.jpg The look and feel of the B1 are both top notch. The body of the version sent to me is black anodised aluminium rather than the natural aluminium I previewed a while ago. On one face are two windows showing the B1's heart - it's discrete amplification circuitry. On the other face are two full-length inserts of black leather (or at least faux leather). The leather inserts make a really nice touch on the black model and add to the sense that the B1 is a classy and elegant amplifier.
     
    Back to those two windows on the other side. Other than allowing a glimpse into the B1's heart, the windows also allow the light of two green LEDs to shine through when the amp is powered up. There's also a power indicated LED (also green) above the power switch so I assume that the in-window LEDs are more for aesthetics than function and they're fine. It might have been a nice touch to hide them somewhere so that only their gentle glow could be seen, creating an ethereal light as though the light were emanating from the B1's soul, but there may be reasons why such fanciful frills were avoided. As it stands the lights are fine. Unnecessary perhaps, but fine and, as I think about it, a window with no light would seem so boring. At least the LEDs mean that you feel like something happens inside the visible circuit when you throw the switch.
     

    Sound

     
    The B1 has a sound that I would describe as clean, crisp and musical with an outstanding sense of space, texture and nuance, but it requires much more explanation than that. With the inclusion of a switch that changes its operation from a normal mode to an "A Class" mode, the B1 can change how it sounds depending on the 'phones you're using.
     
    Based on the headphones I've tried, I'd suggest that the output impedance of the B1 might be high enough to be incompatible with low impedance loads and particularly multi-balanced-armature IEMs. Using the B1 with the Noble K10s results in a thick and lush sound that takes the best features of the K10s and pushes them too far. There are also channel imbalance issues because the volume level is way too high with sensitive IEMs. This is a headphone amp, not an earphone amp (with the possible exception of high impedance IEMs and earbuds).
     
    AuneB1-0253.jpg Importantly though, shifting from the K10s to the Audeze LCD 2s completely changed my experience. Gone is the additional warmth caused by the K10 mismatch and in its place is a clarity and transparency that sounds like a different amplifier. This is all with the mode switch in the normal position too so hold tight if you want to know what happens when that interesting switch gets flicked.
     
    Jumping now from the rich and warm LCD 2s to the leaner HD800s I hear exactly what I thought was happening - the B1 isn't producing the full bass presence or impact when running tougher loads. The LCDs and HD800s are tough in different ways - the HD800s present higher resistance and the LCDs present lower sensitivity - both seem to result in the same outcome when the "A Class" switch is off; a slightly lean and bass-shy sound.
     
    Next, I powered-down the B1 to switch from normal operation to A Class operation in order to see if the extra current fixed the problem...
     
    Well there's definitely a change, but it's subtle (as you'd expect given that the basic circuit remains unchanged). To my ears the sound in A Class mode has a greater sense of warmth and body compared to the normal mode sound when driving the HD800s / LCD 2s. One thing I definitely notice is that the normal mode sounds slightly disembodied and ethereal with the HD800s and LCDs whereas the A Class mode seems to bring the sound back into focus and creates a better sense of body. It still sounds a touch lean with the HD800s, but I am a fan of tube amps with the HD800s because they can tend towards the clinical.
     
    So, while the B1 powers the HD800s amply (no pun intended), the pairing that I have rapidly come to love is with the LCD 2s. In fact, the sound from the B1 + LCD 2 combo is comparable to the LCDs paired with my heavily upgraded Bottlehead S.E.X. amp and that is a seriously impressive feat for a portable amp to come close to a much more expensive desktop amp. Based on what I'm hearing from this combination, I would easily believe it if I was told that the B1 was made to drive planars. Perhaps it was... I don't know, but what if you don't have planars? Is the B1 a good amp for dynamic driver headphones? Let's see...
     

    Fischer Audio FA-011 Limited Editions

     
    With the 160 ohm Fischers, the sound is highly enjoyable and just slightly warmer than neutral. There's good bass presence, nice extension at both ends of the sound spectrum and a crisp and articulate sound overall. Flicking between the normal mode and A Class mode brings about the same slight changes I described above, but the drop-off in bass is nowhere near as prominent with the Fischers as with the HD800s.
     
    The Fischers are a headphone that needs amplification to excel and the B1 most definitely has the chops to get the Fischers singing. I'd very comfortably listen to the Fischers with the B1 as an amp of choice.
     

    Thinksound On1

     
    AuneB1-0252.jpg The On1s are a 50 ohm headphone that's designed for portable use so they're more efficient that the others I've tried thus far. The results here are quite interesting...
     
    With the On1s, the A Class mode creates an overly thick and warm sound that's still enjoyable, but tends to close in the normally spacious sound of the On1s. Switching to normal operation brings a lighter touch to the bass and balances the sound perfectly. The bass is still punchy, tight and deep, but it no longer dominates the soundscape and it lets the On1s return to their more spacious ways. In fact, while completing this portion of the review, Stevie Wonder's Don't You Worry 'Bout a Thing came up in my auditioning playlist (mostly albums that have been awarded Best Engineering Grammy) and blew my mind with the depth and control of the bass. The B1 had the On1s on a tight leash and was manipulating them like a master conductor.
     
    What I'm starting to see at this point is an amplifier that's somewhat of a chameleon, adapting to different headphones as required to always give you the best possible sound. That's a really nice option to have at the flick of a switch!
     
    So, sound-wise and power-wise, the B1 is neutral and clean, but still energetic and musical and it pairs very well with all range of headphones, but not IEMs. Let's look at how it compares to another star portable amp, the FiiO E12DIY.
     

    Aune B1 vs FiiO E12DIY

     
    It's a little bit tricky to make this comparison because the DIY is designed to have changeable op amps whereas the B1 is a discrete (no op amp) design. I decided to play around a bit to find a buffer / op amp combo in the DIY that sounded similar to the B1 in order to compare them less on sound signature and more on general qualities.
     
    Honestly, once the signatures were matched, I would gladly choose either amp to drive my On1s, but keep in mind that the DIY is a special project that should have been worth significantly more than the B1's ~$250 price. The B1 is standing toe-to-toe with a veritable giant at the pricepoint we're considering and I believe the B1 has a slightly better sense of texture and nuances compared to the DIY which means it'll also outperform other portable amps like the standard E12, Cayin C5, and probably the E12A. I don't have those other amps with me to try, but have extensively compared each one to the DIY and always found the DIY superior.
     
    Both amps have sufficient grunt to also power the LCD 2s, but I once again found myself preferring the B1 thanks to its marvelous sense of realism and coherence - everything is just so well placed and balanced.
     

    Overall Summary

     
    Moving through a range of headphones and trying different modes has really left me loving this little black beast with a glowing green heart. Its sound is, to my ears, neutral and accurate without tipping into becoming cold or analytical and it has a sense of energy and PRaT that's beguiling. The fact that you can change operation modes to adjust its synergy with everything from portable on-ears to desktop-only planars makes it extra versatile and extra appealing. This is clearly the best portable headphone amplifier I've tried so far thanks to its great sound and versatility. It's not the best portable amplifier in general terms because it's really not compatible with IEMs and the E12DIY still owns the 'generalist' mantle for that reason (and the versatility of all those different buffers and op amps), but I flat out love the Aune B1 and will be hard-pressed to see it go when the review period is up.
     
    If you're in the market for a portable amplifier for headphones, and you don't mind something of a reasonable size and weight, you should absolutely do yourself a favour and check out the Aune B1. It looks good and sounds better!
      djvkool and Vartan like this.
    1. capnjack
      Nice review Loquah, been debating between this and a Cayin C5 to drive my M-100s and future purchased cans.
      capnjack, May 31, 2015
    2. miceblue
      I like your photos!
      How do you get the formatting for the photos to be in-line with the text though? It makes the formatting of the post really neat, but I haven't been able to do that with the BBCode editor.
      miceblue, May 31, 2015
    3. capnjack
      Well I've finally bitten the bullet and ordered one of these thanks to you, Avitron, Cleg and Cottonijoe for the reviews! :grinning:
      capnjack, Jun 2, 2015
  5. money4me247
    Unique Affordable Portable Amplifier with Clean Sound
    Written by money4me247
    Published Jun 3, 2015
    4.0/5,
    Pros - great value, stylish design, versatile, clean sound signature & solid SQ, unique topology/design as fully discrete Class A portable amp
    Cons - amplifier only, larger & weight size compared to some competing portable amplifiers (Class A/B), lack of accessories, room for design improvements
    Aune B1 portable headphone amplifier Review
     
    2015-06-0219.58.09redsidecropped.jpg
    1. Review unit provided by Aune during its worldwide review tour. Link to program details here
    2. Extensively tested over a period of more than full week (with an extended out-of-town trip)
    3. Will continue to use the B1 for the remaining one week period allocated for the review sample & will update this review as needed
    4. ***UPDATE 6/10/15: I have shipped out the B1 review unit on a USA demo tour (sign-up here)
    5. This is an unpaid and uncensored review covering my own personal subjective thoughts and opinions. I am NOT a professional reviewer. As always, I hope this is an enjoyable and informative read, and remember that ymmv!
     
    Intro: Focusing on achieving high quality sound at a competitive price point while utilizing premium materials and uniquely eye-catching aesthetics, Aune is a Chinese company based in Wuhan specializing in high-end audio equipment. Founded in 2004, Aune is the brand of the largest Chinese audio technology community, http://hifidiy.net/. Aune’s current product line-up include the Aune S16 (desktop usb dac at $699), T1 Mk2 (desktop usb tube dac with a solid state amplifier at $229), the X1 Pro (portable dac/amplifier at $249), and the newly released B1 portable headphone amplifier ($199). The B1 embodies Aune’s philosophy and unique approach with its distinctive styling, emphasis on premium components, and unconventional topology for a portable headphone amplifier.
     
    Tech: The B1 is a fully discrete Class A portable headphone amplifier with its main amplifying circuit comprised of individual triode components. MSRP $199.
     
    2015-06-0219.08.57blackshadowcropped.jpg

    Features:
    1. Pure Class A output
    2. Fully discrete design with no opamps in its entire amplifying circuit
    1. Adjustable Current Output Control (two settings): 40mA and 20mA of static current at 32 ohms, both operating as Class A
    2. Adjustable Gain (two settings): low (5dB) and high (15dB)
     
    Official Technical Parameters:
    1. Impedance: 16-200R
    2. Size: 65*110*18 (mm)
    3. Weight: 230g
    4. typ THD+n <0.0008% @ 1kHz 600RZ/ -0db
    5. SNR > 124dBA @ 600RZ
    6. Flatness +/- 0.15dB @ 10Hz-20kHz
    7. Crosstalk < 100dB @ 1kHz 600RZ
    8. CLASS A: 25mW/16R, 50mW/32R, 100mW/300R
     
    Official Battery Specifications:
    At 32 ohms, the B1’s 4000mA lithium battery provides for 5 hours of continuous current in the high current mode and provides 10 hours continuous current in the low current mode.
     
    ***Will update this review with my personal real-world battery life tests***
     ​
    Design: The Aune B1 is an extremely gorgeous device with a very futuristic and gadgety look. Its styling is serious and stylish enough to draw attention and be appreciated without being too gaudy or garish. It can easily sit unobtrusively in professional settings, especially if placed with the leather side facing up. My geeky side found the view into the insides of the amplifier to be quite exciting and appealing.
     
    The B1 is built with an entirely aluminum chassis bound in synthetic leather covering one side and tempered gorilla glass windows to view the discrete components of the amplifier on the other side. There are two bewitching green LED lights that shine on the circuitry of the amplifier when switched on, drawing your focus towards its premium discrete components. Both sides are well decorated and aesthetically pleasing to the eye.
     
    Special attention was paid to creating a high quality chassis on the B1 with all six sides of the device finished by CNC (Computer-Numerical Control). Anodic oxidation with brushing treatment is applied to final surface with lettering applied via laser. More information about CNC here. More information about anodic oxidation here. On the window side, the name of the device is written in white above the windows with white labeling inscribed at the bottom edge. The three icons are the FCC label, WEEE symbol, and CE mark. There is the inclusion of an unique individual serial number on each device, giving it a premium touch. The leather on the other side also enhances the premium feeling of the device.
     ​
    2015-06-0220.05.50redleather.jpg
    Aune B1 Leather Side
     
    Viewing from the ‘front side,’ the volume knob is placed at the center top with line-in jack on the left and headphone out jack on right. The American-made conductive plastic volume potentiometer functions without any flaws, turning quite smoothly throughout its range with appropriate sense of resistance. The placement of the volume control is very thoughtful. I found it was very unlikely to accidentally adjust the volume even when taking it in and out of my pockets or carrying it in a bag. It is extremely convenient to adjust the volume while it is in your pocket without taking the device out.
     
    2015-06-0218.59.12blacktopedgesideshot.jpg
    Top View of the B1 (minus sign obscured by the glare)
     
    One con noted about the volume pot is that its entire surface is monocolor without any indicator bar to dedicate what volume level is currently used. It is difficult to gauge what volume settings are currently applied or which volume settings are commonly used with different headphones. This can result in accidentally blasting the volume of the amplifier when switching between different headphones or different source devices. I recommend getting into the habit of just always turning down the volume knob prior to usage.
     
    The bottom of the B1 has the micro-usb input for charging located closer to the left side. Left side (going from top to bottom) has a gain switch, adjustable current switch, green LED power-on indicator light, and a power on switch. The right side only has a single LED indicator light for battery/charging along with a small push button to trigger the light.
     
    After pressing the button the the right side, the green battery/charging life indicator will flash a different number of times (1-5) to indicate the percentage of battery life remaining. While charging, the indicator light will continuously blink. Upon reaching full charge, the indicator light will be steadily on. Do note that pressing the button while charging does not do anything.
     
    2015-06-0220.00.52switchside.jpg
              ​
    2015-06-0219.00.35blacktopedge.jpg           
    2015-06-0220.00.20batside.jpg
       B1's Left Side with switches                   B1's Top Side with volume control        B1's Right Side with battery indicator
     
    I do believe that you will not get any additional battery saving with no music playing or lower volume level on your source since the B1 amplifier will supplies a steady continuous current at all times when it is on. I did find that the battery life per current mode seemed to average pretty consistent times quite close to the official estimates. I found it has difficult to catch exactly how long it takes for the battery life to fully charge in my tests, but I estimated that it takes at most 4 hours. In real-world usage, I do not always actively check the battery life, so the device does sometimes suddenly run out of power on me.
     
    My suggestion for improvement on the battery life/charging indicator would be offering another color (such as red) to indicate when the battery life is extremely low. The inclusion of a red color can also be used to indicate charging instead of the current blinking green LED. This would make it much more noticeable when the device becomes fully charged or low on battery with the obvious color change.
     
    2015-06-0219.58.58redglowslash.jpg
          ​
    2015-06-0220.06.21rednoglow.jpg
     ​
    Accessories: A bit lacking. Comes with a 24 inch total length usb to micro usb cable for charging and a 3.5mm-to-3.5mm cable with straight plugs measuring 6.5 inches when plugged in. Below I list the items I feel needs to be bundled as well as items that would be nice to have.
     
    Things NOT currently included, but I think should definitely be included:
    1. Short right-angle cable (3.5mm to 3.5mm) for portable usage
    2. x2 rubber bands for stacking purposes
    3. Longer straight-angle cable (3.5mm to 3.5mm) for desktop usage
    Things NOT currently included, but would be nice additions (not as necessary):
    1. Wall charger
    2. Some type of carrying case
     
    I personally found (for my needs) I would need to use two additional 3rd party 3.5mm to 3.5mm cables. The included cable was just a bit too short for desktop usage and just a bit too long for portable use. I would recommend purchasing an additional short right-angle to right angle cable for portable usage and a long straight connector cable for desktop usage.
     ​
    2015-06-0219.05.31blackwires.jpg        2015-06-0219.05.54blackwindowswires.jpg
    B1's leather side while connected to source                             
    B1's window side while connected to source​

     
    Portable Usage: I rate the B1’s portability ranging from acceptable to great, dependent on user preferences. I personally found to B1 to work well for my needs in the portable setting.
     
    The B1 has larger dimensions and a heftier weight than many other competing portable headphone amplifier designs that commonly employ Class A/B designs rather than Class A. At the same time, the B1 is smaller and lighter than the only other pure Class A portable amplifier using discrete components that I am personally aware of: the now-discontinued Just Audio AHA-120 (80*126*26mm with a weight of 332 grams). I do personally feel that its size and weight is quite manageable as a portable device in real-life usage. My personal measurements for the B1 was 65mm*119mm*18mm.
     
    2015-06-0220.03.14ha2vb1front.jpg
    Size Comparison between the Aune B1 vs Oppo HA-2
     
    There are no rubber bands or other materials included to use in creating a portable stack. Options for stacking will likely include purchasing third-party thick ‘audiophile’ rubber bands designed for stacking portable audio equipment. I personally prefer using third-party velcro-type solutions like the 3m dual lock over rubber bands for stacking equipment, but I was unable to try this option since my B1 is a review unit. The 3M dual lock gives a stronger-than-velcro attachment between devices with an adhesive backing to attach the dual lock strips onto the devices. I can see possibilities for placement of velcro-type strips on the window side of the device above and below the windows for a secure fit.
     
    I would personally recommend stacking the device with the window against the back of your portable player/smartphone as the leather material makes for a very nice grip. At home usage, I like to leave the windows face up to see the cool lights and discrete circuit design. If the light becomes bothersome, simply flip the device over.
     
    One other note for portable usage: this product can get a bit warm on high gain 40mA operation. On the lower setting, I had no concerns about the heat generated by this amplifier and feel comfortable leaving it in my pocket. I personally also felt comfortable with the heat generated during high current operation, but this can be a subjective thing.
     
    I think that the B1 is well-suited for portable usage as long as you do not mind its slightly larger size and weight, and the generation of a bit of heat. Despite lacking a carrying case, the B1 is extremely transportable with a very durable and rugged feeling to its design.
     
    IMPORTANT NOTE: The current adjustment switch should NOT be toggled while the amplifier is on and headphones are connected. This can damage your headphones!! During my extended usage of the B1, I never accidentally toggled of the current mode switch. However, this is quite an important thing to be aware of. I highly recommend testing whether you experience any switch toggling when placing and removing the B1 from your pocket without any headphones connected. I would recommend covering this switch with a small piece of black electrical tape if you have any concerns of accidentally flipping this switch. I do think that a different switch design for the current adjustment that makes it harder to change settings is an area for improvement.
     
    ***Update 6/5/15: I have experienced toggling on the power switch accidentally while the B1 was in my bag. Would recommend placing it in the bag with the switch side facing up to prevent this***
     ​
    Sound Quality:
    1. Dell XPS m1530 & Samsung Galaxy S5 smartphone > Combination of FLAC files, Tidal HiFi lossless, and Spotify Premium Ogg Vorbis
    2. Please use this resource for the definitions of the audiophile terms I am using: http://www.head-fi.org/a/describing-sound-a-glossary
     
    I found it was possible to experience a dramatic improvement in sound quality by adding the B1 for headphones that require additional amplification (especially if the previous set-up was underpowered). The relative differences between different amplifiers are much more subtle. The B1 still remained quite competitive among my personal collection of amplifiers.
    2015-06-0220.11.34-redglowcropped.jpg

     
    The first thing noticeable about the B1’s sound is that it presents a very full bodied sound, but the sound signature remains extremely clear. The B1 can initially appear a bit tonally warm due to better sense of fullness and body presented, but there does not appear to be an overemphasis of warmth (especially apparent in a direct comparison against the warmer-sounding Woo Audio WA7 tube amplifier). The B1 does strongly present a sense of richness and fullness to notes. The instrumental “presence” is very realistic, providing a very lively and engaging sound that seems to be dancing in the room with you.
     
    The B1 never sounds extremely sharp or bright, but still maintains an highly accurate and detailed sound. Do note that I do not possess any pair of headphones that I find to be overly bright in their presentation. I do imagine that if paired with an extremely bright sounding headphone, the B1 will retain that tonal presentation. There did seem to be a bit of an additional sense of clarity and air for headphones that originally possessed that sonic attribute. However, the B1 would not add airiness or crispiness to headphones that did not originally have that kind of presentation.
     
    I found that there appeared to a bit of softening to the transition of the notes due to the nice smoothness at the end of the notes rather than a more abrupt edgier shift between notes. The spacing between notes remained adequate, but very dependent on the headphones used to test. However, the B1 was still very capable at producing clean hard-hitting attack transients with very realistic weight and power behind each note. The bass attack was extremely realistic and punchy. The rich full body and presence underlying the tones was still kept in check with a great sense of control over the bass speed. Attack transients very well represented and extremely tight. A barely audible lengthening of the decay could be detected in comparison. This does provide a bit of a nice smoothness to the sound signature, allowing the music flows very cohesively without ever sounding too abrupt. The B1 helped tighten up the bass notes on headphones with a boomier or flabbier bass response.
     
    The B1 adds a really engaging vibrant element about the bass. There may be a hint of extra mid-bass impact that really brings out a more visceral presence to the bass notes. The B1 also presents a subtly tighter bass and subtle sharpening of treble detail with switching between current modes for certain headphones (most noticeably the orthodynamic headphones in my collection). I felt like there was a noticeable improvement on the HE-560 and HE-1000 using the higher current mode. For the PM-3 and LCD-X, the differences between modes was harder to detect.
     
    The texture and micro-detail of the notes within the midrange was smoothly rendered. The sonic improvements found within the mid-range varied depending on the headphones tested. Do note that changes that I will discuss in this paragraph are quite subtle adjustments. Headphones with a more organic-focused presentation such as the LCD-X became even smoother and more liquid with very fluid changes in tone. While the HE-560 already has a stellar midrange presentation with a high resolution for revealing micro-details, I did feel that the HE-560 greatly benefited from the extra sense of fullness to the body of its notes as its clinical nature sometimes gave the feeling of a bit of thinness throughout the frequency response. The AKG K553 and K7xx maintained a very good balance between an analytical presentation and an organic focus with the pairing of the B1. The PM-3 experienced a notable improvement in its overall sound quality with its smooth articulate midrange further refined. While there were variable amounts of improvements for the mid-range depending on the headphones, I found the B1 to continue to emphasis the sonic characteristics of the midrange each headphone. It did not greatly alter the overall presentation or tuning of different headphones, but presented additional polish to their respective differing sonic characteristics. I did find that the B1 to be a quite transparent and clean sounding amplifier.
     
    I would not characterize the presentation as more intimate or more spacious, but the B1 accurately reflects the presence range and soundstage of the headphones and source tracks being used. It do get a very realistic sense of the instruments being in the room around me. Imaging qualities of the headphones are maintained or even improved. The sound stage significantly improved on the PM-3 as it was easy to hear the difference with the PM-3 slightly intimate presentation. For the other headphones, there was variable subtle improvements to the sound stage, but could be very difficult to detect.
     
    Overall, the B1 provides a highly resolving, rich, articulate sound that stays true to the headphones’ sound signature.
    I decided to use a sampling of currently popular songs from the Billboard top charts as test tracks in addition to my usual test tracks. Covers a wide variety of genres. My list of usual test tracks can be found in my other reviews. List split by genre and ordered alphabetically by artist
     
    Alternative: “Uma Thurman” by Fall Out Boy, “Renegades” by X Ambassadors
    Asian Pop: “Haru Haru” by Bigbang, “Adoration” by David Tao, “Tornado” by Jay Chou, “If Only” by JJ Lin, “The Third Person And I” by Jolin Tsai, “Love Song” by Rain, “Wedding Dress”“by Taeyang, “Heartbeat” by Wang Lee Hom
    Classical: The following is all performed by London Philharmonic Orchestra and recorded by Abbey Road Studios, Royal Festival Hall, and Henry Wood Hall. “Adagio for Strings” by Barber, “Bagatelle In A Minor, WoO 59, Für Elise” by Beethoven, “Nocturne No. 2 In E-Flat Major, Op. 9” by Chopin, “Suite bergamasque, L 75: Clair de Lune” by Debussy, “Symphony No. 5: Adagietto” by Mahler, “The Magic Flute, K. 620: Overture” by Mozart, “Canon In D Major” by Pachelbel, “Finlandia, Op. 26” by Sibelius, “The Four Seasons, Op. 8, Spring: Allegro” by Vivaldi, “The Valkyrie: Ride of the Valkyries” by Wagner
    Country: “Smoke” by A Thousand Horses, “Little Toy Guns” by Carrie Underwood, “Say You Do” by Dierks Bentley, “Sippin’ On Fire” by Florida Georgia Line, “Wild Child” by Kenny Chesney, “Girl Crush” by Little Big Town, “Take Your Time” by Sam Hunt, “Diamond Rings And Old Barstools” by Tim McGraw
    Electronic: “Waiting for Love” by Avicii, “Outside” by Calvin Harris, “Get Low” by Dillon Francis & DJ Snake, “Love Me Like You Do” by Ellie Goulding, “Lean On” by Major Lazer & MO, “I Want You To Know” by Zedd
    Jazz: “I Didn’t Know About You” by Duke Ellington, “Blue Train” by John Coltrane, “The Dreamer” by Jose James, “Songbird” by Kenny G, “There WIll Never Be Another You” by Lester Young, “What A Wonderful World” by Louis Armstrong, “So What” by Miles Davis
    Folk: “Thinking Out Loud” by Ed Sheeran, “Budapest” by George Ezra
    Funk: “Uptown Funk” by Mark Ronson & Bruno Mars
    Indie Rock: “Shut Up and Dance” by Walk the Moon, “Geronimo” by Sheppard
    Pop: “I Really Like You” by Carly Rae Jepsen, “Heartbeat Song” by Kelly Clarkson, “All About That Bass” by Meghan Trainor, “Fight Song” by Rachel Platten, “American Oxygen” by Rihanna, “Elastic Heart” by Sia, “Bad Blood” by Taylor Swift
    R&B: “One Last Time” by Ariana Grande, “I Bet” by Ciara, “Worth It” by Fifth Harmony, “Want to Want Me” by Jason Derulo, “Nobody Love” by Tori Kelly, “Slow Motion” by Trey Songz, “Earned It” by The Weeknd
    Reggae: “I Need Your Love” by Shaggy
    Rap & Hip Hop: “Energy” by Drake, “Trap Queen” by Fetty Wap, “GDFR” by Flo Rida & Lookas & Sage, “Be Real” by Kid Ink & Dej Loaf, “Time of Our Lives” by Pitbull & Ne-Yo, “See You Again” by Wiz Khalifa & Charlie Puth
    Rock: “Bright” by Echosmith, “Sugar” by Maroon 5, “Believe” by Mumford & Sons
    Trap: “You Know You Like It” by DJ Snake & AlunaG
    Soul: “Honey, I’m Good” by Andy Grammer, “Take Me To Church” by Hozier, “FourFiveSeconds” by Rihanna & Kanye West & Paul McCartney
    Soundtrack: “Skyfall” by Adele, “My Heart Will Go On” by Celine Dion, “Atlas” by Coldplay, “Accidentally in Love” by Counting Crows, “Tron Legacy” by Daft Punk, “Will Hunting Main Title” by Danny Elfman, “Let It Go” by Demi Lovato, “I See Fire” by Ed Sheeran, “Lose Yourself” by Eminem, “May It Be” by Enya, “Aggressive Expansion” by Hans Zimmer, “Concerning Hobbits” by Howard Shore, “Spirited Away - One Summer Day” by Joe Hisaishi, “Star Wars Main Theme” by John Williams, “I See the Light” by Mandy Moore & Zachary Levi, “The Godfather Love Theme” by Nino Rota, “Everything Is Awesome!!” by Tegan & Sara & the Lonely Island, “I Will Always Love You” by Whitney Houston


     
    Headphone Pairings:
    *******Important Notes*******
    Tested with my source volume maxed, only controlling volume via the B1's pot
    Tested each headphone listed on the B1 against the same headphone with:
    1. no amplification
    2. the Oppo HA-2 lineout to amplifier only
    3. the Schiit Lyr 2 desktop tube hybrid amplifier (best amplifier in my collection imo)
    *********************************
    I could not fit my thoughts on how my entire collection of headphone pairs with the Aune B1 in this review.
    Link HERE for further detailed impressions on specific headphone pairings with the Aune B1.
     
    Overall thoughts on headphone pairings: I do want to note that some of my comparative findings were quite extremely subtle changes that required very extensive direct comparisons and even then, I am still a bit hesitant about certain aspects of my findings. Please note that you may have different experiences due to differences in our headphone and amplifier background.
     
    The B1 had minimal coloration to each headphones unique sound signature. Improves different aspects of sound quality on each headphone while maintaining the headphones’ original tuning and frequency response. Suitable pairing for headphones that you are already satisfied with its sound signature. Not suitable as a method for trying to ‘tune’ or adjust to the headphones’ sound signature, and will not ‘fix’ frequency response flaws of your headphones. Can cause a dramatic improvement for headphones that benefit or require additional power. More subtle degree of improvements for headphones that can be driven without an amplifier.
     
    2015-06-0218.58.43blackside.jpg
     
    Direct Amplifier Comparisons:
    *******Important Notes*******
    1. Compared the performance of each amplifier against the B1 using the AKG K7xx, PM-3, and HE-1000
    2. I believe the K7xx and PM-3 are very highly resolving neutral-orientated headphones that are strong representatives of high quality mid-tier open and closed categories. I also used the HE-1000 as it is the most resolving headphones in my collection with the greatest scaling potential.
    3. Please remember these are my own personal subjective impressions. YMMV!!!
    *********************************
     
    Against the Cozoy Astrapi portable dac/amplifier:
    MSRP: $139.99 (can be found for $129.99) - Portable usb dac with solid state amplifier (unspecified, but most likely Class A/B)
    **Cannot compare against the amplifier portion only as it has no line-in**
     
    Design: The Astrapi is much smaller, more compact in all dimensions, and much lighter. Very portable dac/amplifier combination. No internal battery and is powered by the connected smartphone.
    Sound: Astrapi has bit warmer overall sound signature with a smoothed-over treble. While the Astrapi has very competitive sound quality at its price point, it is not as resolving and technically proficient as the B1. The most noticeable differences is that the B1 has a larger soundstage with better sense of imaging, a cleaner more neutral-oriented sound signature, more revealing of micro-details and subtle textural variations, more realistic sense of presence to the body of notes, and a better defined quicker transient response.
    Overall thoughts: Astrapi has competitive performance for its price point and excels as a portable all-in-one amp/dac solution for those requiring the most minimalist slim design. Consider the Astrapi if portability, size, weight, and small form factor as your primary concerns. More suitable for those who enjoy a subtle hint of warmth in their sound signature.
    Personal Pick: Application specific. I use the Cozoy Astrapi when extremely limited pocket space or when I do not want to carry a lot of extra stuff with me. The Astrapi is extremely portable and very convenient. The Astrapi does not require recharging as it draws power through the usb from the source device. I use the B1 during travel (vacations, airplane flights), commutes (subway, driving), or on-the-go when I don’t care about pocket space. Also, I would use the B1 if concerned about smartphone battery life as the B1 does not drain any power from your smartphone.
     
    Against the Oppo HA-2 portable dac/amplifier:
    MSRP: $299 - Portable solid state Class A/B amplifier with dac (ES9018-K2M dac chip)
    **Compared against the HA-2’s amplifier section only via the line-in**
     
    Design: The HA-2 is thinner, taller, and lighter with the dimension of 68*157*12 mm and weighing 175 grams. The HA-2 also is leather-bound with a metal chassis.
    Sound: The sound quality between these two amplifiers was extremely difficult for me to personally detect even after very extensive direct comparisons. Only when using the HE-1000 could I really even begin to really pick what exact differences consistently. The only comments I am comfortable making is that there appears to be a bit extra sense of fullness and body on the B1. There may also be a subtle underlying richness on the B1 that is harder to detect on the HA-2. The B1 seems to have a harder hitting attack and a bit more texture to its bass notes. Perhaps a bit more cleanly defined bass and a subtle mid-bass emphasis compared to the HA-2. The B1 has a bit more breathiness. I do think the comparative differences is also dependant on the headphones that are being tested, so don’t take this comparison too seriously as ymmv! I do personally think that the differences between well-designed solid-state amplifiers can sometimes be extremely hard to pick out in a blind test. I view significant differences as sonic aspects that can be easily picked up within one or two quick direct comparisons. I had to do much more testing to find differences in performance between these two amplifiers. Overall, it appears that both these amplifiers are quite well-designed and provide extremely solid sound quality.
    Overall thoughts: The HA-2 was my personal pick as an external amplifier/dac solution after extensive research, and I do personally find it well suited for my needs with very competitive performance at its price point. I consider it to be a ‘premium’ portable amp/dac combo while staying within the affordable price range. I used the HA-2’s amplifier via line-out to extensively compare against the B1.
    Personal Pick: Tied. I think the different design characteristics of these two devices will primarily determine which one is more suitable for your intended application. The sound quality between the two devices are both extremely competitive and it was extremely difficult for me to consistently isolate the exact differences in sonic characteristics.
     
    2015-06-0220.03.48b1vha2side.jpg          2015-06-0220.05.05ha-2vb1top.jpg
    Oppo HA-2 vs Aune B1 Side View                                                 Oppo HA-2 vs Aune B1 Top View

     
    Against the Resonessence Labs Herus usb dac/amplifier:
    MSRP: $350 - USB dac with solid state amplifier (ES9010-2M dac chip)
    **Cannot compare against only the amplifier section as no line-out**
     
    Design: The Herus is thicker but much shorter in width and length. It also weighs less. The Herus’ boxy design makes it less unsuitable for portable usage (in my personal opinion) as it does not stack well. No internal battery, so will be powered by your smartphone or computer.
    Sound: The Herus has an overall brighter sound signature and sounds ‘crispier.’ Extremely clinical-oriented presentation in my personal opinion. May sound sharp depending on your treble preferences.
    Overall thoughts: The Herus is more suited for desktop usage, but extremely transportable. Can possibly use portably, but not the best choice for that application in my personal option. Consider the Herus is you require a stand-alone usb dac and amplifier combination and enjoy a brighter presentation.
    Personal Pick: Aune B1 (especially B1 paired with a dac of my choosing)
     
    Against the Schiit Lyr 2 desktop tube hybrid amplifier:
    MSRP: $449 - Dynamically Adaptive Class A/AB tube hybrid amplifier
     
    Design: Desktop solution, not portable at all. Chassis becomes extremely hot!
    Sound: Slightly warmer and fuller sound with subtle tube coloration. Noticeably second harmonic distortion for a “tubey” sound. I personally find the Lyr 2 to have a very well-refined balance of an engaging euphonic richness while maintaining great detail resolution and technical performance. Extremely good sound quality attributes including spacious soundstage, precise imaging, tight transient response, vivid sense of energy, sturdy control throughout the dynamic range, and highly resolving micro-detail retrieval. I do think that the Lyr 2 is a superior technical performer though the B1 remains relatively competitive and close in overall performance.
    Overall thoughts: Not a direct competitor product. This is my personal favorite amplifier out of my collection and I believe it is a strong performer at its price point. The relative difference in performance was much smaller and more subtle than I expected from my direct comparisons. I was really surprised by the relative closeness in performance of the B1 to the Lyr 2 despite the Lyr being one of the most competitive options in the sub-$1000 category. While I still think that the Lyr 2 offers the best overall sound for my tastes out of my amplifier collection, the B1 is quite technically capable amplifier and stays extremely competitive. The B1 may even be preferable for audiophiles do not enjoy the slight euphonic coloration provided by tube amplifiers and are looking for minimal coloration in their amplifier.
    Personal Pick: Schiit Lyr 2 in desktop applications
     
    Against the Woo WA7+WA7tp desktop tube amplifier:
    MSRP: $1,398 - Pure Class A transformer-coupled tube amplifier
     
    Design: Desktop solution, not portable at all. Can get a bit hot.
    Sound: WA7 has a much warmer sound. Very noticeable coloration in direct comparison. Pleasant euphonic distortion, “richer sound.” Soundstage and imaging not quite as large or precise with a more intimate presentation and subtle emphasis in the presence range. A subtle rounding and smoothing of notes with a blurring effect in the transient response. Spacing between notes not as tight. A bit longer decay times. Focuses more on presenting a ‘liquid’ smoothness to the textural shifts rather than highlighting the micro-details.
    Overall thoughts: Not a direct competitor product. The WA7 may be suitable for people looking for an all-in-one desktop pure tube amplifier solution with a dac. I feel that the WA7 is better for people who enjoy a very warm, smoothed-over, pleasantly colored sound signature, and strongly appreciate the aesthetic design of their products.
    Personal Pick: Aune B1 in both portable and desktop applications (especially with a dac of my choosing over the WA7’s built-in dac)
     
    ***Update 6/5/15: I have done direct sighted comparisons of the B1 against a few other desktop amplifiers using the HE-1000. Not a fair comparison I know, but I have found that I could hear a subtle differences in sound quality against the Hifiman EF100. It was more difficult to hear the difference against the Audeze Deckard. There was a significant upgrade in sound quality in a sighted test (specifically with the Auralic Taurus MKII, Beyerdynamic A2, and McIntosh MHA1000). Differences were most pronounced in the MHA1000 which I found to be the best sounding amplifier out of all the ones I tried. Extremely life-like and gorgeous sound! The direct comparision with the MHA1000 is the first time I noticed extremely significant scaling with external components. A direct comparison against Chord Hugo did not yield that much of a sonic improvement to my ears. The sonic upgrade was significantly more easily noticeable on the MHA1000 over the Chord Hugo in my opinion. The Chord Hugo alone definitely does not drive the HE-1000 to its full potential. Using these amplifiers and dacs, I could definitely see how the HE-1000 scales up greatly with different components and would recommend investing in a more high-end amplifier for the HE-1000 to maximize its potential.***
     
    ***possible additional amplifier comparisons (including the Liquid Carbon and the Oppo HA-1)***
     
    Value Judgement: Excellent
     
    I would personally always recommend an external portable amplifier or external portable dac/amplifier combination over an audiophile-targeted dedicated audio player. You can normally get more competitive amplifier and dac components at the similar price point and you have more versatility as you are not tied down to the player’s UI and can use your smartphone/laptop as a source as well.
     
    Considering that many smartphones and computers have quite capable dac chips nowadays, I do believe it is quite reasonable to skip an external dac (especially for a portable set-up). The nice thing about a standalone amplifier is you can choose your own dac pairing, ranging from inexpensive budget dacs such as offerings from Hifimediy or Stoner Acoustics or more expensive options like the Cypher Labs Algorhythm Solo.
    Fiio E6 ($27.99)
    JAD Labs cMoyBB v2.03 ($59)
    Fiio E10k ($75)
    Creative Sound Blaster ($49.99)
    Fiio E11k 2 ($59)
    Fiio E12 ($129)
    Cayin C5 ($159.99 on Amazon, MSRP $239)
    JDS Labs C5 ($189)
    HeadAmp Pico ($349)
    Ray Samuels Audio Emmeline P-51 Mustang ($375)
    Ray Samuels Audio Emmeline Hornet ($370)
    HeadAmp Pico Slim ($399)
    Ray Samuels Audio Emmeline SR-71A ($450)
    HeadAmp Pico Power ($475)
    **Just Audio AHA-120 (~$535 in 2013, discontinued): fully discrete Class A portable amplifier
    Fostex HP-V1 tube amplifier ($549)
    Cypher Labs Algorhythm Duet ($599)
    iQube V5 ($699)
     
    **Note: Just Audio AHA-120 is a discontinued portable Class A amplifier using fully discrete components with a slightly different feature set that retailed at the $500+ price point.
    Do note that if you are looking for a compact external amplifier/dac, the B1 will not suit your application.
    Fiio E07k Andes ($89 on Amazon - MSRP $99.95,)
    Fiio E17k Alpen 2 ($139.99 on Amazon - MSRP: $249.99,)
    Fiio E18 Kunlun ($159 on Amazon - MSRP: $299.95)
    Creative Sound Blaster E5 ($199.99)
    Leckerton UHA-4 ($199)
    Beyerdynamic A200p ($219.99 on Amazon - MSRP $349)
    JDS Labs C5D ($249)
    Leckerton UHA-6S MKII ($279)
    Oppo HA-2 ($299)
    Sony PHA-1A ($299)
    Leckerton UHA760 ($399)
    Fostex HP-P1 ($449 on Amazon - MSRP $799)
    Sony PHA-2 ($449.99 on Amazon - MSRP $599.99)
    iFi Audio micro iDSD ($499)
    CEntrance Mini-M8 ($599.99)
    Centrance HiFi-M8 ($699)
    There are also usb stick-sized dacs with built-in amplifiers that can feature a much more compact design, but will generally not have as nice quality or powerful amplifier. Majority of these options also requires special OTG adapter for Android devices or a lightning camera connection kit for iPhones to utilize the dac. Some examples include the Audioengine D1/D3, Audioquest Dragonflyv1.2, CEntrance Dacport, HRT Music Streamer line-up, LH Geek Out, Meridian Explorer 2/Director, Resonessence Labs Herus/Herus+, and Schiit Fulla.
     
    For people looking for an high-performing dedicated portable amplifier, the B1 is a very appealing high performing option with an affordable price point. From my research, I do think the B1’s price point is quite competitive for its unique topology and design even among the current market offerings.
     
    Considerations for Prospective Buyers:
     
    My Overall Ratings (as I believe the side-ratings on head-fi are averages):
    Do note that I hardly ever give out full score ratings even on extremely good products. Reserve that rating for products that I feel far exceed and redefine my previous notions of what is capable
     
    Audio Quality: 9/10
    Design: 8/10
    Quality: 8/10
    Value: 8/10
    Overall Score: 4/5
     
    The greatest sonic pro of the B1 in my mind is its full, rich, detailed sound with minimal coloration. The B1 has extremely competitive high-quality sonic performance even above its price point with the versatility to work with a wide range of headphones from sensitive low impedance IEMs to high-impedance dynamics and hard-to-drive orthodynamics. It also features a stylish design and a very competitive price point.
     
    The biggest con in my mind with the B1 is the lack of accessories (especially the lack of a short right-angle connector often provided by competitors even at lower price points). I do strongly feel that those accessories should be included at this price point. There is also room for improvement to its design (marking the volume pot, indicator light improvements, possible concerns of accidentally switching the current switch). Other important properties of the B1 that warrant individual consideration are listed below.
     
    Important considerations for potential purchasers:
    1. A dedicated amplifier only. May not suitable for those looking for an all-in-one dac/amplifier combination. Does give the flexibility of pairing with personally preferred portable or desktop dacs (especially helpful if you have different dac preferences for different headphones). This can be a pro or con depending on your requirements.
    2. Class A design will generate heat and requires a larger footprint/weight compared to some of the other portable amplifiers on the market (especially compared to traditional Class A/B designs). My personal experience with the B1 was not really affected by those factors, but how those qualities of the B1 affect you will be a personal subjective call.
    3. Battery life ranges from 5-10 hours. May not suitable for those looking for an portable amplifier that can last multiple days without charging (though do note whether its battery life is sufficient for your needs will be dependent on your usage habits).
    4. Should work with the majority of headphones on the market as I was able to test it with high impedance headphones (DT880 600 ohms) and some orthodynamics. Do note that all Audeze and Mr. Speaker headphones are easier to drive than the HE-560 from a technical specification standpoint. However, the older Hifiman headphones such as the HE-4, HE-400, HE-500, HE-5, and especially the HE-6 are harder to drive than the HE-560 from the calculated power requirements and I was not able to test the B1 with any of those headphones. Pairing the B1 with the old Hifiman headphones will require additional research (ask for impressions from owners).
    5. Does not drastically ‘tune’ your headphones’ sound signature by adding excessive coloration. Not suitable for those trying to find an amplifier to significantly alter their headphone’s sound signature.
    6. Does NOT have a bass boost feature. Not suitable for those who are looking for that specific feature or are looking for a heavy bass quantity emphasis. Do note that the B1 does offer sonic improvements to the bass quality.
     
    Conclusion:
     
    The B1 provides ample power for all the headphones I tested with a clean black background. It adds minimal coloration to the sound signature, so the source and headphones can be heard accurately. Providing sonic improvements to the weight, fullness, and richness of notes throughout the frequency response, the B1 is extremely detailed, highly resolving, and true to source.
     
    A quite strong application of the B1 that may be overlooked is using the B1 as a stand-alone ‘transportable’ amplifier. I personally found this to be the B1’s best strength. It’s small size in comparison to other ‘transportable amplifiers’ allows for a very easy carry from one location to another. Whether going to work/school, travelling between hotels, or moving between rooms in the house, I found the B1 to really shine in that setting. Plugged into a laptop, there is no need to worry about checking the battery indicator lights for battery life.
     
    I personally found packing the B1 while travelling on vacations or business trips added a great deal of convenience as one piece of nice audio setup. Not only can it be used while on-the-move (flying in airplanes, sitting in subways, walking on the street), but it can be used while working at Starbucks or chilling in the park. I do strongly feel the B1’s sound is extremely competitive even beyond other portable amplifiers with performance that allows it to be used as a viable alternative to traditional desktop amplifiers. I have personally been utilizing the B1 the most often as a "transportable desktop amplifier."
     
    While it is possible to use the B1 purely on-the-move in your pocket as well, the B1’s larger size and weight compared to the competition makes it bit less suitable for that specific application for the general consumer audience (in my personal opinion). I would personally recommend the B1 more for the really serious audiophile who emphasize sound quality over convenience and the portability of their audio stack. Other audiophiles I think this product would greatly appeal to are audiophiles with multiple different listening locations who would benefit from an easily relocatable  “transportable” amplifier solution. Finally, audiophiles requiring portability with multiple dacs and various headphones may appreciate the standalone approach to an external amplifier providing clean power for dac and headphone synergies to truly shine.
     
    While I do personally think that Class A topology does not inherently mean a superior sounding amplifier, I found the B1 to be an good example of well-designed, well-implemented Class A amplifier with solid sonic performance. I am not aware of any other currently in production fully discrete Class A portable amplifier, so this device seems quite unique. While this device may not be for everyone, I would highly recommend audiophiles interested in high performance affordable portable amplifier to audition the B1 as it has very compelling sonic performance for its price point.
     
    ***UPDATE 6/5/15: Please check out this post HERE if interested in signing up for a home audition of my review unit. My demo tour will last as long as there are interested people wanting to try this item. Please post on that thread or PM me directly***
    ***UPDATE 6/10/15: My US tour of the B1 has officially started & has been shipped out***
     
    2015-06-0219.11.09woodglow.jpg
     
    Product link: http://en.auneaudio.com/html/en_products1/Portable_series/190_11.html

      aluweer, CPhoenix, Anjolie and 6 others like this.
    1. View previous replies...
    2. WhiskeyJacks
      I had never even heard of this, when did it come out?
      WhiskeyJacks, Jul 24, 2015
    3. money4me247
      @WhiskeyJacks, I am not 100% sure the exact release date, but it came out this year. Earliest thread discovering the B1 on head-fi is here (1/21/15). First head-fi review written by @cleg (2/14/15). Aune's official sponsored thread posting on the B1 here (4/8/15). Aune's head-fi review tour announced here (5/10/15) with an impression thread created here on 5/21/15.
      money4me247, Jul 25, 2015
    4. yacobx
      excellent review!
      yacobx, Mar 6, 2017
  6. hakushondaimao
    Class A Portable Amp With Class
    Written by hakushondaimao
    Published Jun 7, 2015
    4.5/5,
    Pros - Stunning looks, high quality build and materials, power to burn, natural sound with strong mids.
    Cons - Gets quite warm on high gain, slightly bass-light and rolled-off treble, limited fine volume adjustment with IEMs.
    0Main.jpg
     
    Disclaimer
     
    I received a sample unit of the B1 portable amplifier from Aune Audio as part of a worldwide review tour. I was able to keep the unit for 10 days, during which I used it extensively. I did not have to pay for the unit; only for postage at the end of its tenure with me. The only expectation of tour participants was an unbiased review once we had given the B1 enough time for a fair evaluation. I am not affiliated with Aune in any way.
     
    About Me
     
    To begin, here's a little context. I’m 50 years old, and am pretty sure I have deficiencies in my hearing. In a recent, entirely non-scientific test I discovered I can’t really hear anything over about 15 kHz, with roll-of starting around 12 or 13 kHz, which is actually pretty good for someone of my vintage. I also like to crank things more than the average bear to get the volumes I desire.
     
    I’ve been a music lover for decades, but am still relatively new to the MidFi/HiFi/Head-Fi game; I haven’t listened to a lot of high-end equipment, and am not an expert on the technical aspects of electronics or musical terminology. I have read a lot of reviews and threads on Head-Fi, and spend a lot of time on the site; as such I know what has been helpful to me in reviews and endeavor to provide what I consider useful insight to help others make decisions about items they might want to try or buy, or avoid.
     
    I listen to a variety of music genres, in particular, Classical (mostly mid 1700s to mid/late 1800s), Jazz (late ‘50s to early 70’s), Rock and some Prog-Rock (‘70s), ‘80s New Wave/Electro, and Trip Hop/Acid Jazz (90’s into 00’s). My preferred sound signature would be characterized by a good sub-bass presence, tight mid bass, and relatively linear, detailed mids and highs. I like my music quite lush and rich, but with a good level of detail. I’m not a bass-head, am not a big fan of anything too boomy, and don’t like highs that are too intense or harsh.
     
    Unboxing and First Impressions
     
    As usually happens when I receive a new piece of equipment, I was excited to get the Aune B1. The unit arrived by courier from Hong Kong, so first order of business was to get the protective packaging off. Thankfully, not a big job, and in a couple of minutes I had box and protective material removed.
     
    1Box.jpg
     
    The B1 comes packaged in a solidly constructed, textured black cardboard box. Even before lifting the lid, one has the impression of quality and pride in this product.
     
    2BoxOpen.jpg
     
    3Stuff.jpg
     
    Opening the box reveals two compartments within an intricately cut and folded corrugated cardboard inlay. In the large compartment one finds the B1 amplifier, within a thin, semi-opaque plastic sheath, and in the other, smaller compartment are the Micro USB charging cable and 20cm-long 3.5mm-to-3.5mm interconnect. Under the B1 there is a basic, folded instruction sheet, with Chinese information on one side and English on the other.
     
    4.E12AB1C5JPG.jpg
     
    The B1 unit has a good heft to it. It has similar length and width dimensions to the Cayin C5 and Fiio E12A, but is a bit thicker (E12A = 14mm, C5= 15mm, B1 = 17mm). It is available in Black with black trim, or silver with red trim. I received a black B1.
     
    5FrontRight.jpg
     
    The front of the B1 is gorgeous! Two glass windows reveal a circuit board with various chips and resistors. The effect is both hi-tech and artistic, and gives a highly unique feel. The only thing on the right side of the unit is the battery level indicator; press the button and a small light blinks: 5 times for full battery, 4 for 80%, 3 for 60%, 2 for 20% and 1 for 10%).
     
    6light.jpg
     
    When the power is turned on, a small green light turns on in each window, giving off a tube-like glow. When ambient light is low, the glow from the B1 is quite mesmerizing and moody.
     
    7Back.jpg
     
    The back of the B1 is flat with nothing but the brand name and model number, and two strips of what looks like textured leather. The leather is slightly raised, providing a soft surface for resting the unit, or for mounting a DAP when stacking (the leather helps avoid scratching). The leather doesn’t grip too well though, so a stacked DAP will tend to slip and slide unless using double bands to hold units together.
     
    8Top.jpg
     
    At the top of the unit you find the volume pot, and headphone-out and line-in jacks. The volume pot is metal, with ridges for grip, sits flush (not much to catch on things in a pocket) and feels tight and solid. Turning is not difficult, but it does offer good resistance to inadvertent adjustment while on the go.
     
    9Left.jpg
     
    On the left side you find the power control, Class A current adjuster (20MA or 40MA), and gain switch (low gain is +5dB, high gain is +15dB).
     
    10Bottom.jpg
     
    On the bottom is the Micro USB charging plug-in.
     
    11Front.jpg
     
    12Back.jpg
     
    The silver version of the B1 is quite attractive. The red leather back is quite striking in contrast to the silver aluminium chassis. Both colours of B1 are attractive and have a quality feel about them.
     
    Listening
     
    In my review I did some general listening using the Fiio X3ii as source, using a variety of over-ear headphones (Sennheiser HD650, Audio Technica ATH-R70x, and AKG K7XX). I also performed several comparisons to other portable headphone amps (Fiio X3 2nd generation’s internal amp, Cayin C5 and Fiio E12A), using a variety of IEMs (Noble 6, T-Peos Altone 200, and Havi B3 Pro 1). Some of the equipment I used in my reviews was my own, and some was provided by 3rd parties for review purposes.
     
    General Listening
     
    Listening 1: Norah Jones – Come Away With Me
    ALAC > Fiio X3ii > Aune B1 > Sennheiser HD650 (Low Gain, Volume 6/10)
     
    1. The B1 is rated at 16-300 ohms, and the HD650 is a 300-ohm headphone. As such, one would naturally expect this combination to be at the limit of the B1’s capabilities. At 6/10 and on low gain, volume was right where I like it (I like my Vs) and detail excellent.
    2. In “Come Away With Me,” there is a lovely sound of brushed snare throughout that I find beautifully soothing; this was clear and textured. There is also a lovely, low-key guitar solo half-way through the song; this was atmospheric and high notes sparkled. Norah’s voice was full, with her characteristic airy, textured tone. The B1 dealt with both song and headphone very well. Very enjoyable.
     
    Listening 2: Sade – Bullet Proof Soul (from Love Deluxe)
    ALAC > Fiio X3ii > Aune B1 > Audio Technica ATH-R70x (High Gain, Volume 6/10)
     
    1. The R70x is rated at 470 ohms. Of all the headphones I own, this was always going to be the ultimate test for the B1. Perhaps it was unfair to even attempt this one based on power ratings, but some manufacturers under-rate their amps so I figured I’d give it a try (as an example, the Fiio E12A is designed for IEMs and rated at 16-300 Ohms – same as the B1 – but it drives the R70x exceedingly well).
    2. If you’ve read any of my other reviews, you’ll know that this is my favourite song for sub-bass, and I just love the combination of Sade’s vocal with those of her back-up singers (depending on equipment, these backing vocals sometimes don’t come through very well). The B1 dealt with all challenges very well. Volume reached more than satisfactory levels at 9/10 on low gain, and 6/10 on high (high gain sounded better; on low gain I felt there was just a touch of distortion). R70x test passed!
    3. My initial listen to this track was done on the low current setting. Curious about the Class A current adjustment (have never played with any Class A equipment before), I did a little reading and learned that with high powered phones or speakers, higher current beefs up bass and extends treble. Decided to give Sade a listen again on the high setting, and found this to be the case with the B1; the effect was subtle, but highs and lows had just a bit more authority.
     
    Listening 3: Duke Ellington & Johnny Hodges – Beale Street Blues (from Back To Back)
    ALAC > Fiio X3ii > Aune B1 > AKG K7XX (High Gain, Volume 5/10)
     
    K7XXX3ii.jpg
     
    1. Even though only rated at 62 ohms, the K7XX is known to have low sensitivity and is notorious for being hard to drive and requiring amplification. This track is a lolloping blues number, with sultry sax, piercing trumpet, lively backing piano, and some fun, low-key guitar and drum riffs. The K7XX is beautifully driven by the B1. All instruments are presented clearly, with great texture, balance and detail. Stereo imaging and soundstage are excellent, with good space and instrumental placement. A very pleasant listen!
    2. After running the B1 on high gain for around an hour through the 3 general listening stages of this analysis, I noticed the B1 getting rather warm. I wouldn’t say it was uncomfortably hot or anything, but it was warm enough that you might notice it in a pocket. Not a bad thing in winter, but perhaps not the greatest in summer.
     
    Comparisons
     
    Comparison 1: Beethoven – Cello Sonata No. 3 (played by Timora Rosler and Klara Würtz)
    320 kbps AAC > X3ii > Aune B1 > Noble 6 (Low Gain, Volume 2.5-3/10)
    320 kbps AAC > X3ii > Noble 6 (Low Gain, Volume 65/120)
     
    1. This is another favourite track for testing, with the interplay of rich tonality and range of the cello with energy and sparkle of the piano. The Noble 6 is a linear, neutral IEM, and I’ve found it doesn’t pair particularly well with overly analytical sources.
    2. With the X3ii+B1 combination, this piece sounded marvellous. Sound was rich, with great body, richness and texture from the cello, and a lively, realistic tone from both left and right hands of the piano. Range on the volume pot was limited at a low volume setting of around 2.5-3/10, with little room for fine-tuning of volume.
    3. With the X3ii un-amped, I had more range to play with and much finer control over volume settings. That said, sound quality at equivalent volume was less satisfying than with the B1 combination. On it’s own, the X3ii produced a less lively, less nuanced, more veiled performance. Cello was smoothed, and the piano was a bit one-dimensional. There were also touches of harshness in the treble that I could see being fatiguing in a more extended listening session.
     
    Comparison 2: Steely Dan – Gaucho (from Gaucho)
    ALAC > X3ii > Aune B1 > T-Peos Altone 200 (Low Gain, Volume 2.5/10)
    ALAC > X3ii > Fiio E12A > T-Peos Altone 200 (Low Gain, Bass Boost off, Volume 4.5/10)
     
    Altone200X3ii.jpg
     
    1. Another favourite test track for atmospherics and micro detail, both vocal and instrumental. The Altone 200 is often described as bright (I don’t find it overly so), and delivers good, strong bass.
    2. These two amps had quite different characters. E12A had great bass quality (sub and mid), along with excellent detail and texture in mids and highs. Texture and detail of snare drum, bass, guitar, and sax were excellent. Sound stage was open and had depth.
    3. B1 was more mid-forward, with more subdued bass and highs. Bass isn’t as much rolled off as recessed, while there was some roll-off in trebles. Texture of main and backing vocals, and body of sax (though a bit smoothed), were more satisfying with the B1. That said, stage seemed a bit more constricted.
    4. While I enjoyed the music from both amps here, I found the E12A more extended in high and low frequencies, and B1 more mid forward. I liked the range in the volume pot for an with the E12A; this was again a bit limited with the B1, which I feel may be better suited to more demanding IEMs and cans.
     
    Comparison 3: Pearl Jam – Jeremy (from Ten)
    ALAC > X3ii > Aune B1 > Havi B3 Pro 1 (Low Gain, Volume 5/10)
    ALAC > X3ii > Cayin C5 > Havi B3 Pro 1 (Low Gain, Bass Boost off, Volume 4/10)
     
    HaviCayin.jpg
     
    1. This is a great track for comparisons, especially of male vocals and energy. The dual-dynamic Havi has an almost cult following. It is known to have a wide open sound stage relative to other budget IEMs, with good texture and extension, especially in treble (some find the bass a bit on the dry side).
    2. The Cayin C5 sounded fantastic, with lovely tonality of bass, “school bell” and drums in the opening of the song. Eddy Vedder’s vocal texture was clear and throaty, dry and rasping. Electric guitars were full of energy, clear, with no muddiness. High-end was a touch harsh and fatiguing. Space and good instrumental definition in performance, staging was open and wide.
    3. With the B1 bass was less prevalent, again with a more mid-forward presence. Gong sounds fuller than with C5. Vedder’s vocal, guitars and drums were clean, warmer, smoother than the C5. High end less harsh, less fatiguing than from C5. Soundstage smaller.
     
    Conclusions
     
    There’s a lot to like about the Aune B1. It drives powerful headphones with authority, and has a lovely mid-forward sound that is easy on the ears and suitable for long, fatigue-free listening sessions. Design is phenomenal, with great looks and a quality build and feel. If I had the power to improve anything about the B1, it would be 1) greater range on the pot for fine volume control, and 2) slightly more extension of bass and treble.
     
    IMG_6308.jpg
     
    In comparisons with other popular portable amplifiers, I’d equate the B1 to the Sennheiser HD650 (contolled bass, mid-forward, clean, easy on the ears) and the Fiio E12A and Cayin C5 to the Audio Technica ATH-R70x (more natural extension of bass and treble). If you’re an HD650 type, you will really like the sound signature of the B1. If you’re more into the R70x, you’ll still enjoy it, especially for longer listening sessions.
    1. View previous replies...
    2. hakushondaimao
      hakushondaimao, Jun 11, 2015
    3. Baycode
      Thanks for this thoughtful review Hakus, now I have an idea what B1 sounds like :)
      Baycode, Jul 5, 2015
    4. hakushondaimao
      @Baycode: Glad to help, and thanks for the comment.
      hakushondaimao, Jul 6, 2015
  7. creatip
    A little amp with class
    Written by creatip
    Published Jun 7, 2015
    4.0/5,
    Pros - Very stylish and elegant, good sound, long running time, good value for the price
    Cons - A bit big, gets warm with use
    So I got this unit from Aune as a part of their worldwide review tour. This is actually the second Aune product that I got the chance to tinker with. First one being Aune T1 MKII Tube DAC/amp, which I bought a while ago and has been using ever since. If you wanna read my review on the T1 MKII, you can find it here. I like to think that both of them is like brother and sister :)
     
    On with this review then.
     
    Unboxing
     
    IMG_0669_zps5ua4onng.jpg
     
    One thing I like about Aune is their box presentation. Aune's products are mostly in the middle level price range, but their box looks so nice and elegant. The box alone instill the sense of 'class' to anyone who sees it. 
     
    IMG_0679_zpsidc5gqq7.jpg
     
    Open it up, and you'll find a few stuffs inside. From left to right:
    - USB to micro USB cable for charging. 
    - Mini stereo 3.5mm to 3.5mm interconnect cable, gold plated.
    - The main unit, the B1 Headphone Amp (I will be referring it as 'B1' from here on)
    - The box
    - Aune's business card. The writings on it are all in Kanji (Chinese) though, so I couldn't make any sense of it except for phone numbers and e-mail addresses.
    - User manual.
     
    IMG_0717_zpsr7b82xlg.jpg
     
    IMG_0774_zpsvwvxz0ie.jpg
     
     
    Now this unit is beeeaaauuuutiful!! I really love the design. They come in 2 variant/color scheme, the all black, and the silver/red like the one in the picture. Usually I like my devices all black, but I couldn't resist that beautiful silver-red combo. It's simply stunning!. Honestly, it's the most stylish portable amp I've ever seen. 
     
    The design reminds me a bit of those liquor hip flasks, especially the volume knob on top. The leather side is actually the back side of the amp. The leather layer protrudes a bit, making it a soft cushion when you put it on hard surfaces, avoiding scratches and dusts to the aluminum case.
     
    IMG_0816_zpsvrol3pi4.jpg
     
    This is the front side of the amp. It got a twin window to showcase the discreet amp parts (more about this later), and two LEDs that lights up when it's powered on. 
     
    IMG_0804_zpslxu83vdr.jpg
     
    IMG_0834_zpsg3g007fk.jpg
     
    The unit measures approximately 12 cm + 6 mm protruding button = 12.6 cm height, 16.5 cm wide, and 1.7mm thickness. It's about as big as an Iphone, but thicker.
     
    IMG_0805_zpsbhxhut7f.jpg
     
    On one side, there are 3 buttons, the power button, 'class A' (current gain) button, and the volume gain button. On the other side, there's a battery checker button with a small LED. Press this button, and the LED will blink to show how much battery is left. 5 blinks = full, down to 1 blinks = 10%.
     
    IMG_0807_zpsrtuaeiiz.jpg
     
    On the top side, there are two jacks. The left one for audio output, the right one for line/signal input. Volume knob in the middle.
     
    IMG_0809_zpsc7mq0bjj.jpg
     
    On the bottom side, there's a micro USB input for charging. 
     
    IMG_0739_zpspcbqofvi.jpg
     
     
    Now what really make the B1 so special compared to other portable amps, are 4 things: the design, class-A amp architecture, discreet op-amp, and high current setting. The design part was already explained above, so I won't go further with that part.
     
    - Amp class. You can find more info about various audio amp class in wiki and articles on the net. In short, class-A amp is an amp architecture that's both simple and has the least distortion, compared to other amp architectures/classes. The drawback of a class-A amp is that it needs constant electric current running through it, even when there's no signals to be processed. Because of this fact, there are two more drawbacks, which are: bigger power consumption, and more excess heat. The B1 gets warm after about 30 minutes of continuous use. Not dangerous hot, of course, just warm. Warmer compared to other portable amps. If you got a vintage speaker amp that's very heavy and got a big heatsink in the back, it may very well be a class-A amp. Because of the drawbacks, especially the power consumption, class-A architecture is rarely implemented in a portable amp. That's one of the thing that sets the B1 apart. It's like they're breaking through the common stereotype. Of course they got the battery to match the bigger power consumption. 
     
    The warm temperature is a bit of a let down actually, especially for those who live in tropical climate like me (southeast Asia). Again, it's not too hot to touch (which would indicate something is horribly wrong with the device), just lukewarm. When used in tandem with my T1 (on my PC desk), I just point a USB fan to the B1, and it effectively countered the heat effect. 
     
    - Discreet op-amp. Portable amps usually use op-amp chips, because they're less space-consuming, and more efficient. Discreet op-amp basically means they substitute an op-amp chip with a whole set of electronic circuit, pictured in the twin window of the B1. The benefit of this is that they can then fine tune each components (resistors, capacitors, etc) the way they like it, as oppose to plugging a factory-made op-amp chip, and accept whatever the result will be. This is of course debatable, whether or not the discreet op-amp implementation gives a better result than an op-amp chip, because the end results aren't fully determined by the op-amp part alone. Nevertheless, the use of discreet op-amps (1 for each channel) makes the B1 unique. 
     
    - High current setting. When it's set to off, or 'low', the B1 will give out 20mA of current. When it's set to on, or 'high', the B1 will give out 40mA of current. The bigger current amount is useful when it's used to power less sensitive and low impedance headphones. This is usually the case with older generation of planar headphones, like the Hifiman HE-400 I'm using. Lacking in current in the signal output will mostly make the sound distorted, like when you turn the volume of your speaker amp too high, and the speakers start to sound unpleasant. Let's see if I can 'show' you:
     
    [​IMG]
    *sorry about the noises in the left channel. I think it's the left mic's cabling. The right channel is working normally. I only found out about this when uploading to youtube, and I'm too tired to record a new one...[​IMG] Maybe I'll record a new one later.
    ** oh and that small piece of tissue paper is not part of the setup. It's there because the headphone is too big on the dummy head.
     
    That dummy head got a pair of separate channel mics embedded in its ears. So the sound you're hearing is actually the sounds coming from the headphone. The recording volume was set to very low, because in reality that was quite loud. I have to set it loud, to the distorting level, to show the effect. Now of course this video can't be treated as 'this is how the B1 or the headphone sounds', because the stuffs I got there (mics, cables and connections, and ADC) aren't studio recording standard. This setup degrades the original sounds by quite a lot. I'm just trying to show how the current gain affects the sound. 
     
    The video encoding seems to alter the sound a bit. This is the WAV extracted from that video: https://soundcloud.com/marcus-sudjojo/current-gain The difference is more audible in the WAV version.
     
    Pay attention to the first part (current gain switched to low), the kicks were distorting. Not much, but still audible. In the second part (current gain switched to high), the kicks weren't distorting, and got tighter and more 'dense'.
     
    This is also a special case, powering an inefficient and low impedance headphone with a portable amp. For portables uses, such as on-ear headphones or IEMs, the low current gain setting is more than enough, because portable stuffs are usually pretty efficient anyway.
     
    Current gain is NOT a volume gain, so setting it higher does not mean you will get louder volume. The B1 already got a separate volume gain switch for that. So if you're using the B1 at the low current gain setting, and you don't hear any distortions, it's best to leave it at low setting, to preserve the battery, and make it run longer.
     
    I have to be honest, with the current gain switch like that, it's a bit of a design faux pas from Aune. They explicitly state that the switch must not be flipped when the B1 is running. Problem is, with the design and position of the switch, it's very easy to flip it by mistake/accident. If you ask me, they should have implement some sort of locking mechanism, so the switch can't be flipped unless you open the lock first. Fortunately, I asked them if there are any danger if the switch is flipped accidentally while running, and they replied, there are no danger, plus the headphone plugged to it is perfectly safe.
     
    One more thing to note is their long life battery. Their 4000mAh built-in battery is claimed to be able to run it continuously for 10 hours at low current gain setting, or 5 hours in high current gain setting. Of course with big battery capacity comes the counter-effect: longer charging time. I charged the B1 with my Ipad 10W wall charger, and it still took a couple of hours. The good news is, it can continue running while charging. So for example, the battery dies when you're on the road. Well, you can plug the USB charger cable to your power bank, and you can keep enjoying your music. 
     
    The B1 also got a good electronic architecture that enables it to output the same stable good sounds until the battery runs out. I've encountered a few portable amps that output deteriorating sounds as the batteries are about to run out. That's not the case with the B1. I was enjoying my songs when the sounds suddenly stopped because the battery ran out, with no deteriorating sounds whatsoever.
     
    Oi, enough about the technicalities, we wanna know how it actually performs....
     
    Well, first I'd have to state the fact that I believe: out of the whole chain (DAC - amp - headphone/speaker), the headphone/speaker got the most margin of difference between one another. The DAC and amp got less margin of difference in that chain. So you can't, for example, buy a $1000 amp, plug a $30 headphone to it, and expect it to magically transform the headphone into a $1000 one. Different DACs and amps can, and will, alter the resulting sound to some extent, for better or worse, just in a smaller scale than different headphones will. So keep in mind that what I'm saying next is in a smaller scale.
     
    I tested the B1 with 3 headphones:
    - Audio Technica AD700 (without X)
    - AKG Q701
    - Hifiman HE-400
     
    IMG_0823_zpsi47ntmhn.jpg
     
    First impression I got when I plug the B1 to my Ipad (yeah, I'm not too crazy on portable devices) is that the B1 is dead silent. The 'silent test' is usually the first thing I test in headphone amps. Plug it to the source, with nothing playing, max out the volume knob. If there's any noise floor audible, then it's not really a good headphone amp. Well, like I said, the B1 is dead silent, or 'black' as some people prefer to call it. After the silent test, comes the actual listening test. The B1 'smoothen' out the edges in the songs. It's not a big secret that older generations of idevices (mine is the ipad 3) only got mediocre internal amp. When plugged to the B1 (via LOD), the mediocre quality of my ipad's internal amp got pointed out immediately. The songs sound as smooth as silk. There are no 'rough edges' between different frequencies and instruments. You might say it's a lot more transparent and less distorting. The frequency separation is very good. I could even hear some subtle sounds that weren't there when I plug a headphone straight to the headphone jack of the ipad. 
     
    I played various songs, like Celine Dion's that's known for 'unforgiving' to bad devices (thus make a good test song). Her voice could sound very rough and sharp when played through bad devices. From Celine Dion, to U2, to Tong Li, to EDM like in the video. Every songs I tried came out so much better compared to the ipad's internal amp. Even my old (and mediocre) AD700 sounds so much better with the B1. 
     
    IMG_0759_zpssdqcplp8.jpg
     
     
    But wait, like said above, I already got the T1, right? The T1 can output line out through the RCA jacks in the back. So of course I'd give it a go. Man, the B1 really outperforms the T1's internal amp. T1's internal amp is already quite good (that's why I'm using it daily, as my main device), but the B1 amp is really 1 level above it. Fed from the tube DAC of the T1, the B1 really performs its money worth, and beyond!! The sound I got was spacious, warm, rich, and yet smooth, with minimal rough edges. 
     
    For people who are used to V-curved sound (like myself), the low frequencies will feel a bit lacking at first. It's lacking, not completely gone, though. I could still fully enjoy EDM songs with the B1. What it's lacking, it gives back in clarity and frequency separation. The high frequencies are very clear but not intrusive. The mids got more density to it.
     
    Now I think I understand why Aune insists on implementing class-A architecture in the B1. To be honest, I've never encountered any portable amps that give this kind of result. If you have auditioned various portable amps, try the B1, and most probably you'll agree with me. 
     
    Now if your music preferences is 'rocking it out loud', and you're looking for something that's 'head-kicking, bass-thumping, heart-pumping' kind of sounds, the B1 might not be the perfect choice for you. I'd say the B1 is more aimed for quality, not quantity. 
     
    IMG_0829_zpsrocaudwj.jpg
     
    The 'siblings', T1 tube DAC/amp and the B1 Headphone amp. Zippo for size.
      aluweer and Synthax like this.
  8. Buhagim
    Who says retro style impacts sound quality? Think again, Aune have bags of both with this stunning little performer
    Written by Buhagim
    Published Jun 8, 2015
    4.5/5,
    Pros - Transparent - deathly silent, built for being thrown around. Class A amp with a 10 hr. battery. Enhances smartphone audio experience
    Cons - Limited accessories. USB can't charge smartphone - only charges the B1. Volume knob needs a mark to show degree of rotation. No case or rubber bands.
    Introduction:
    I'll admit upfront that if you're expecting to read an in depth, technical review - you'll likely be disappointed. Other reviewers on this site have covered this little gadget in much more depth – in fact I'd argue they were writing a thesis on it. For those that like that sort of thing – all’s well and good - you may stop reading here.
     
    For those of you still with me I'd like to take a different perspective. A short and to the point overview with a focus on what the Aune B1 was designed for - quality portable sound. 
     
    What's in the box?
     
    The professional black packaging foretells I was in for a treat and I wasn't disappointed. Lifting the lid reveals a minimalist but adequate set of:
     
    1. A business card from Aune (complete with a lovely protective tissue paper)
    2. Mini stereo 3.5 to 3.5mm connector cable (not sure of quality - looked adequate)
    3. User manual/ leaflet 
    4. USB to micro USB charging cable
    5. The B1 amp (black “pleather” on brushed black aluminium in my case - red on silver also available)

    D71_2585-001.jpg D71_2587package.jpg
     
    First Impressions – look and feel
    First impressions of the B1 remind me of looking at a sturdy hip flask. It has that sort of grab and hold it in your hands shape. Very retro – very chic. Instead of a screw off lid we have a plastic (albeit dense and high quality) volume knob. The comparison goes a stage further too – with recessed “hips” all the way around adding to the flask shape and providing a utilitarian function too. It protects the slide switches from accidental changes perfectly 
     
    This thing is built to withstand a truck driving over it! It is absolutely solid – the sort of solidity and heft you’d you imagine a gold bar might have. No give, no twist – it just exists and the mass helps to dissipate heat? 
     
    The first side has two textured "pleather" insets which give the B1 an air of quality and again plays to the retro styling beautifully. Then comes the wonderful surprise. You turn it over and there in all their glory are two small windows giving you a glimpse of this “badboy’s” internals. Immaculately soldered and perfectly symmetrical surface mounted components mirror (I’m guessing here) left and right channels and their associated power /control circuits. 
    D71_2607-002hipflaskshape.jpg
    I’ve taken a magnified picture (below) to show the quality of the workmanship. Truly a delight to behold and again an indicator of things to come.
     
    I flicked the power switch, hoping there was some juice in the 4,000mAh battery and was rewarded with two satisfying relay clicks. The B1 was alive and two green LEDs were now illuminating the windows. Very hypnotic – and I haven’t even listened to it yet. I love the see through panels.
    In the hand the B1 is weighty – but not heavy. At 200g its not something you slip into a pyjama pocket and forget about in a hurry! However, it’s carriable in a ruck suck/bag or large overcoat pocket alongside your chosen portable source.
     
    Pros: Solid, Robust, lovely retro styling, windows and pleather
    Cons: No bands to hold your gadgets together, connector could have right angled ends to reduce cable distance to piggy backed gadgets
     
    [​IMG]
    Gadget orientation and beauty shots:
    This gallery captures the key faces of the B1. Features of note are:
    1. Glass window panels
    2. Pleather insets
    3. Gain ( - is 5dB, + is 15dB) , Amp current (- is 20mA, + is 40mA) and power switch slider switches on one side
    4. Volume, 3.5mm stereo in (from source) and 3.5mm analogue stereo out (to headphone/IEM) on top side
    5. Micro USB charging port on bottom (only charges the B1 can't use it to power/recharge a USB gadget)
    6. Single "dot" LED and button to indicate battery charge level (number flashes indicates state of charge- 5 is max)
     
    D71_2691-001hipflask1.jpg D71_2687-001hipflask2.jpg
    Recessed slide switches for gain, amp power and device power on/off - picture shows windows on one face and the soft pleather inserts on the other.
    D71_2613-002circuitwindow.jpg
    Close up of the circuitry through one window. (Click for larger file)
    D71_2684usb.jpg D71_2650volumeknob.jpg
    Micro USB charging port on base of B1. This does not charge other devices - it's only  for getting the B1 powered up.Top surface has volume knob and 2 x 3.5mm stereo sockets - note: no indicator/mark on the knob to show its position - makes it difficult to know what volume setting you have reached. A simple "dot" on the top or a white line on the gnerled edge would be more than sufficient and an easy fix.
     
    D71_2653-002batteryindicator.jpg D71_2654-001gaincontrols.jpg
    Close up of the slide switches and battery indicator.
     
     
     
    So how did it perform ? What did I think of it?
     
    Bullet point notes on usage:
     
    1. B1 took about 2 hours to charge using high current charger
    2. The battery usage figures seem broadly accurate at 10 hours use for low gain and 5 hrs at high
    3. Recessed sockets didn't prevent use of headphone plus I tried though you might find a l low profile set that could foul.
    4. Yes it got warm - but not hot. The metal case helps to lose heat and I noticed when it was close to my computer's fans it cooled really quickly as they sucked air across its surface.
    5. Could do with bands to hold the B1 to the Smartphone
    6. The lack of a "mark" on the volume control meant playing safe and moving the volume low each time i tested - a bit of a faff - was tempted to mark it with a little correcting fluid!
     
    Bullet point notes on sound:
    1. Outstanding reproduction for such a small device
    1. Volume control is smooth . I tested it with full volume and max source output and no background noise or hissing.  This thing is deathly silent, even when it's ramped up. More importantly it's transparent. I mean sonically it's giving a flat response neither favoring high or low frequencies.  What does this mean ? Well, having tried it with the MDAC,  the samsung S3, the desktop computer and the samsung tablet,  what you hear it's what you put in. It's very clean.
    2. The overall impression I got was that the sound from the B1 had "atmosphere" and "presence" it didn't distort, it simply made it more enjoyable.
    3. I tended to prefer the settings at full gain and full power as they seemed more solid.
    4. The B1 does have an effect on the sound, you get atmosphere. The music becomes fuller,  the bass more controlled.  Where it makes a difference, and that seems to depend on the source,  the music comes alive.  
     
    Sound Stuff
    All source tracks are streamed from TIDAL - high res audio to avoid issues of poor source quality. These were played sequentially via:
    1. TIDAL> My PC (on board sound card using Realtek ALC898 codec) > NAD Viso HP50 - A/B with the B1)
    2. TIDAL > Samsung S3 >NAD Viso HP50 - A/B with the B1
    3. TIDAL > Sonos> Audiolab MDAC > NAD Viso HP50 - A/B with the B1
     
    Track: Once upon a time in the west - Dire Straits remastered - Communique
    I thought I'd found a weakness in the B1 when I could hear hissing on the track.  I double checked,  without the B1 in circuit, only to find it was on the original sound track. So much for transparency! For the record the drum rolls on this track are simply superb and tighter with the B1 in use. The snares, cymbals and vocals are separated. A foot tapping good listen. Again with the B1 in place,  the samsung S3 sounded more controlled and fuller.
     
    Track: Bullet Proof Soul - Sade
    This is a real test of very low infra-sound. You feel it rather than hear it.  Again the B1 held it together,  it reproduced the bass without muddying it. It was nicer to listen to the B1 for extended periods.  Great atmosphere and a real presence to the sound.
     
    Track: Idle Moments - (Rudyard van Gelder 24 bit remastering)- Grant Green
    Just for the sheer pleasure of listening. .I gave up A/B swapping, left the B1 on max gain and max power...and sat back to enjoy a beautifully rounded sound from sax, piano and drums on a solid sound-stage. 15 minutes of chilling!
     
    Track: Young and Foolish - Bill Evans - Everybody Digs Bill Evans
    Surprised how good the sound from the S3 actually was - but then when I added the B1 it tightened up - again the B1 was transparent, felt "fuller" and "more robust" - it was more controlled and offered better separation- I can describe it like "being in the same room as the artist" - a real room atmosphere. Definitely enjoyable.
     
    Track: Mahler: Symphony No. 2 in C Minor - "Resurrection"  - Weiner Philharmoniker
    I wanted to see how far I could push the B1 so I played a really mean trick.  Mahler is notoriously difficult to listen to. Tens  of instruments,  percussionists, volumes ranging from quiet to loudest of the loud.  An audio system assault course! And the 1st movement of symphony no. 2 - Resurrection is no exception. I wasn't expecting a lot. What I got was a surprise.  Again the B1 was transparent. The complex arrangements of cymbals,  drums,  trumpets, horns and violins were all in control and faithfully reproduced.  No,  I didn't get a huge sound-stage but then the real thing fills an entire auditorium!
     
    Note: Across all these tracks the MDAC through the B1 didn't add much - perhaps a little more solid but really got too subtle for me to distinguish and by this time i was wanting to enjoy the music. They are both Class A amps and equally good to my ears. So I'd argue the B1 was transparent in this scenario.
     
     
    Conclusions:
    If you're looking to add some extra atmosphere to your music on the go and want to drive a decent pair of headphones the Aune B1 is worth putting onto your shortlist. It's looks alone are worth it, the Class A amp in such a robust package clinches it for me. I've enjoyed using Aune B1 over the past week. It's solid, looks a quality device and really adds something  to the sound experience. I'd recommend giving it a listen and seeing for yourself how transparent and atmospheric it is.
     
     
    The listening set up:
     
    D71_2683-001MDACandSonos.jpg D71_2667-001.jpg
    Sonos played through MDAC and TIDAL played through Samsung S3 , B1 and NAD Viso HP50's.
     
    D71_2657NADandAUNE.jpg
    1. Note: I tried my Shure 215 IEMs as another listening option and found they were easily over powered by the outputs from the B1 - not that it didn't add anything - however the quality compared with the VISO HP50s really wouldn't make it a value for money purchase. This balance would change instantly if the IEMs were in the next league / quality up - however I couldn't test those on this occasion.
     
     
    B1 Specifications (as published by Aune):
     
    1. Impedance: 16Ω - 300Ω
    2. Size: 65 mm × 110 mm × 18 mm
    3. Weight: 230 g
    4. Typical THD+n: <0.0008% @ 1 KHz, 600Ω / -0dB
    5. Signal/noise ratio: >124 dB @ 600Ω
    6. Flatness (Frequency range): 10 Hz – 20 KHz ± 0.15 dB
    7. Crosstalk (Channel separation): > 110 dB @ 1KHz  600Ω
    8. Class A Output power: 25 mW @ 16Ω, 50 mW @ 32Ω, 100 mW @ 300Ω
    9. Battery: 4000 mA/h
    10. Battery Life (vs drain current): 10 hours @ 20 mA, 5 hours @ 40 mA
     
     
    Disclaimer:
    Yes, I won a freebie B1 from Aune for a trial period. No, it hasn't influenced my comments - I am being as transparent and objective as if I'd borrowed it from a pal. For the record, the freebie sample was for a trial "loan" period after which it has to be returned. Hope that covers off all the naysayers [​IMG] 
      aluweer and nick n like this.
    1. View previous replies...
    2. money4me247
      enjoyed reading your review. great selection of test tracks with Mahler! :) love that song!
      money4me247, Jun 13, 2015
    3. avitron142
      Nice review! Well done!
      avitron142, Jun 13, 2015
    4. Buhagim
      Thanks guys. Appreciate your feedback
      Buhagim, Jun 14, 2015
  9. ClieOS
    Full Discrete Class A portable amplifier
    Written by ClieOS
    Published Jun 13, 2015
    4.0/5,
    Pros - Sound Quality, Build Quality, Price.
    Cons - High Output Impedance, Short Battery Life, Relatively Low Output Power.
    Originally running a well-known audio DIY forum in China, the company behind the Aune brand has managed to turn itself into a fairly reputable audio brand in recent years, producing mainly PC based desktop Hi-Fi gears. As far as I know, the B1 portable amp that is going to be reviewed here is the company’s first foray into the portable amp market – and not a run-of-the-mill design at that. Not only does it has a fully discrete design, it is also running at Class A configuration. That sound promising on paper, but does it deliver?
     
    [​IMG]
     
    Spec
    Recommended Headphone Impedance: 16~300ohm
    Size: 65 x 110 x 18mm
    Weight: 230g
    Typical THD: Less than 0.0008% @ 1 kHz, 600 ohm / -0dB
    SNR: More than 124dB @ 600 ohm
    Frequency Response: 10Hz ~ 20kHz, +/- 0.15dB
    Crosstalk: Less than 110dB @ 1kHz, 600 ohm
    Power (Class A): 25mW @ 16 ohm, 50mW @ 32 ohm, 100mW @ 300 ohm
    Gain: +5dB / +15dB
    Dual Quiescent Current: 20mA / 40mA
     
    [​IMG]
     
    [​IMG]
     
    Build Quality
    To say B1 is ‘well built’ is almost an understatement – it is drop-dead-gorgeous! The aluminium housing is very well machined, smooth to the touch without any sharp corner. Two transparent windows in the belly allow you to peek inside the amp circuit and two faux leather strips on the top that not only look good, but also serves as a cushion for any device you want to strap onto the B1.
     
    If there is any real complaint that I have, I’ll say the volume knob is a bit too low profiled / oddly shaped, making it harder to adjust volume, especially when there is two 3.5mm plug next to it. Last but not least – and not really a complaint here but more of a suggestion – as Aune warns that the current switch must not be used when B1 is turned on, I’ll think a more logical choice will be to make the switch even more recessed than it is now so it won’t get accidentally switched by any chance.
     
    Battery Life
    Aune quotes that B1 has a 10hours play time running on 20mA mode and half that with 40mA mode. I actually get a bit less, probably around 3~4 hours in 40mA, though it really depends on the load as well as the volume. Suffice to say, the battery life isn’t exactly great. Given it is a Class A amp that isn’t known for power efficiency, I guess that much is expected.
     
    [​IMG]
     
    [​IMG]
     
    Gain, Hiss and EMI
    B1 comes with two gain settings: +5db and +15dB. Personally, I’ll think it would have been better with +3dB and +12dB, as the current setting might be too high for sensitive headphone and IEM, getting too loud (or even worst, channel imbalance) with just a small turn of the volume knob. I will even consider a zero or negative gain setting being helpful for those with really sensitive custom IEM.
     
    There is almost no hiss to speak of. There is in fact almost no ‘click and pop’ during start up as well. B1 is very well behaved in those regard. There is however some EMI issue. Cell phone interference can be picked up in close proximity, though not particularly loud and therefore not a serious concern.
     
    Tech Prelude
    So what is Class A - and if it is that good, why didn’t we see more of it? To put it simple: music is in wave form, swing from one end to another and back for a whole 360 degree. A Class A amp is a device that continuously operates the whole 360 degree non-stop. In the process it usually will waste a lot of power and generate a lot of heat, though it is also considered to be better sounding by many. Most of the amp (and mainly the opamp used) in the market however are in Class A-B configuration, where only half the components are active. The active half is where the signal is, and the inactive half only switches on when the signal arrives. It is far more efficient than Class A, but has its own problems - namely more distortion as components are switched on and off all the time and signal gets distorted when traveling from one end to the other. But at the end, Class A-B is usually the choice for portable gears due to practicality, as the distortion really isn’t bad enough to outweigh the benefit of less heat and much longer battery life.
     
    Being full discrete means there is no integrated circuitry in the signal path. It is just another way of saying no opamp but rather individual discrete components (resistors, caps, transistors, etc) is used for amplification. B1 isn’t the first full discrete portable amp I have seen and this kind of implementation does require a lot of attention to detail, especially on parts matching, to show how good it is. A really well implementation can really sound exquisite, just as good as any top tier opamp based portable amp.
     
    [​IMG]
     
    Sound Quality
    As usually, my SQ assessment starts with an RMAA measurement, and the result is pretty good. No issue can be seen and the number match up with my reference O2 nicely, which is a very good sign. In fact, B1 outperforms O2 noticeably on stereo crosstalk, no doubt thanks to its dual-mono discrete circuitry that keeps the left and right channel further apart than what opamp usually does. However, the result on current output as well as output impedance is really less than stellar. First, the output impedance is rather high - measured and calculated to about 10 ohm, which is no good news for multi-drivers IEM. Second, current output is fairly low. Aune listed B1’s output power of 25mW @ 16ohm is quite low for a portable amp, and my measurement pretty much confirm it. In contrast, a FiiO E06 can pump out 4 times more power on the same load. One thing I noticed is that B1 @ 20mA mode begins to clip when I pushed the volume too high (regardless of gain setting) during my RMAA measurement (*with a 47ohm load). This is independent of the input volume so my guess is that it is running out of current to remain in Class A at such a high volume, as the clipping on high volume disappears once I retest it on 40mA mode. From both the prospective of SQ as well as battery life, I think easy-to-drive load probably can stay happy with 20mA mode, but anything more demanding should perform better in 40mA mode, though battery life will be cut short. Regardless, both modes don’t really have a lot of current output to speak of. In my opinion, this is very likely the inherent issue of being Class A – trying to push for higher output and you will end up with a portable heater that doesn’t run for very long; trying to keep everything reasonable and the output power will be limited, as in the case of B1. Technically speaking though, I think B1 is better suited for higher impedance headphone rather than lower one.
     
    [​IMG]
     
    [​IMG]
     
    Subjectively, B1 sounds really good, as good as any top-tier portable amp I have heard. It also sounds rather clean and neutral, pretty much comparable to my reference O2 for that matter. While still very clean sounding, the mid does sound slightly more hollow in 20mA mode, giving the illusion of extra airiness and a bass kick that is stronger than it ought to be, which can be interpreted as being more powerful than the amp is capable of, though not really the case as I find the texture on the midrange, especially vocal, incomplete. Bass note, while has a good kick to it, does sound thinner than it should. Everything however snaps back to normal once switched to 40mA mode – the vocal is restored and all elements are inline again, though no more ‘extra’ airiness. But I don’t consider that a loss as B1 already has a really excellent soundstage and imaging. It makes a pair of flat sounding ER4S feel almost like surround sound, and that’s a wonder of its own and pretty much the best soundstage I have ever heard on a portable amp that doesn’t have any EQ enhancement. Despite not having a lot of power in measurement, B1 doesn’t sound like it is lacking power in 40mA mode. It is not the tightest in control, but it doesn’t sound loose either. All and all, it holds up quite well
     
    [​IMG]
    Size Comparison (from left): FiiO E12DIY, Aune B1, and Leckerton Audio UHA-4
     
    Sum-up
    I really like B1. It is well built and it sounds great – if it isn’t for multi-driver / very low impedance headphone and IEM, I have no problem recommending it. Aune took on the challenge to manufacture a Class A full discrete portable amp and they almost able to knock it out of the ballpark. Sure, there are still a few kinks here and there – but for as good as it is, Aune really deserves some credit. It isn’t the portable amp for every occasions – but where it does work, it works really well.
     
    This review is part of Aune Worldwide Review Tour:
    http://www.head-fi.org/t/765999/aune-b1-headphone-amp-worldwide-review-tour-reviewers-wanted
      zhibli06 and money4me247 like this.
    1. View previous replies...
    2. Evshrug
      Nice review! Sounds appealing, though for something high-quality portable like this to NOT suit equally high-quality portable like the higher-end IEMs with 3-12 drivers does seem to be a head-scratcher. Good that it breathes new life into the classic Etymotic though!
      Evshrug, Jun 14, 2015
    3. AuneAudio
      Hello , thanks for the good review , we will upgrade  the headphone impedance in the next version of B1 , thanks 
      AuneAudio, Jun 15, 2015
    4. ClieOS
      Good to know. While under 1 ohm will be great, I think anything under 2 ohm will be good in my book.
      ClieOS, Jun 15, 2015
  10. miceblue
    A Solid "Portable" Amplifier for the Price, With a Unique Twist
    Written by miceblue
    Published Jun 14, 2015
    3.5/5,
    Pros - Overall aesthetics, sound quality, silent background, discrete Class A design, Class A switch sonic characteristics, voltage output, price
    Cons - Build quality, volume knob, not stackable, thickness, too much gain, current output, I/O placement, battery life, battery charge time, charge noise
    DSCN9285.jpg



    [rule]
    DISCLAIMER
    I received this B1 unit for a two-week period in order to provide Aune with some feedback on it in the form of a review. Details of the opportunity can be found here in the original thread:
    http://www.head-fi.org/t/765999/aune-b1-headphone-amp-worldwide-review-tour-reviewers-wanted

    I want to thank Aune for giving me the opportunity to be a part of this program, and I look forward to seeing how future products will turn out from the feedback provided!



    Note #1:
    I'm experimenting with a different formatting style while writing this review. Long reviews when viewed on the mobile website tend to look like a giant essay and it's hard to pick a section of the review that's relevant to you, so I'm putting the different sections in spoiler tags. If you guys could provide some feedback on it, I would greatly appreciate it and it would help me make better-formatted reviews in the future. Thank you in advance! : )

    Note #2:
    Since Head-Fi takes the average of the detailed ratings on the left, I'll list what I rated the B1:
    • Audio Quality: 4/5
    • Design: 3/5
    • Quality: 3.5/5
    • Value: 4/5
    Overall: 3.625/5, rounded down to 3.5/5 stars



    [rule]
    Video Review


    0:16 - Thank you to Aune Audio
    0:41 - Sound quality A/B test methodology
    1:39 - B1 vs OPPO HA-2
    2:20 - B1 vs FiiO E12
    3:35 - B1 vs JDS Labs C5/C5D
    5:54 - B1 vs JDS Labs Objective 2
    7:53 - Sound quality overview
    8:36 - Price-sound quality value
    8:51 - Gain switch voltage output
    10:02 - Class A switch current output
    11:05 - Class A amplifier design overview
    11:41 - Battery life
    12:23 - Class A switch's sound
    14:05 - Aesthetics overview
    15:03 - Mute relay
    15:27 - Input/output overview
    15:42 - Volume knob
    16:43 - Front panel window and component overview
    18:52 - Size and portability
    20:24 - Stackability
    21:39 - Aluminum chassis overview



    [rule]
    There's not much in here:
    • Aune B1
    • Aune business card
    • B1 user manual
    • USB A-microUSB cable
    • 3.5 mm-3.5 mm straight interconnect

    I made a silent unboxing video on my YouTube channel if anyone is interested in it. It was made for ASMR purposes, so it'll be really weird to watch for 99.99% of the people reading this review.

    Video Table of Contents:
    4:30 - Box overview
    6:32 - Opening the box
    6:49 - Aune business card
    7:01 - B1 user manual (Chinese)
    7:25 - B1 user manual (English)
    7:55 - USB A-microUSB cable
    8:03 - 3.5-3.5 mm interconnect
    8:24 - B1 overview (I wanted the camera to focus on the component window, but it didn't work sadly; it's in the video thumbnail though)
    9:40 - Turning the B1 on
    10:25 - B1 size comparison with Nintendo 3DS



    [rule]
    I won't go into great detail here but I think the power output, size, mass, and battery life specifications are pretty important to know.
    Full details:
    http://en.auneaudio.com/html/en_products1/Portable_series/190_11.html

    Power output and derived voltage and current outputs from Ohm's Law:
    16250.63239.528
    32501.26539.528
    3001005.47718.257


    I received official confirmation from Aune themselves that the B1 outputs 3 Vrms in low-gain mode, 6.5 Vrms in high-gain mode at 1 kHz 0 dBFS signal.

    The maximum input signal into the B1 is 2 Vrms.


    Size:
    • 65 mm (width)
    • 110 mm (height)
    • 18 mm (depth)

    Mass: 230 g

    Battery Life:
    • 10 hours while operating in the 20 mA mode
    • 5 hours while operating in the 40 mA mode



    [rule]
    Classes of amplifiers are determined by how the amplifying transistors are biased (with current). Class A amplifiers always have the amplifying transistors always on and always biased. The amplifying transistors are thus never turned off and are always active whether or not there is a signal to be amplified. Because of this, they are extremely inefficient in terms of power management, and that's why they tend to get warm due to energy being dissipated as heat.

    Two advantages for this kind of amplifier design though is that it's extremely responsive since the amplifying transistors don't need to have a wait period between turning on/off, and it's extremely linear. Class A amplifiers have the ability to amplify a signal linearly with little distortion as long as they are properly biased to operate in the linear region.

    The Class A switch of the B1 alters the static current, or Class A bias. Of course demanding a higher, always-on, current correspondingly affects the current draw from the battery, and thus lowers the battery life. No surprises there. I also don't think it's just coincidence that the highest current output of the B1 is also the number for the high-current mode, 40 mA.



    [rule]
    The overall aesthetics of the B1 are simply stunning in my opinion. An all-metal chassis, viewing window to see the interior PCB and discrete components, and synthetic leather on the back all make it look very impressive.
    DSCN9264.jpg

    DSCN9227.jpg



    The term "discrete components" just denotes basic electronic parts with no special integrated circuit components such as operational amplifiers (op-amps). The Class A amplifying circuit is built entirely out of these individual transistors and no op-amps are used.
    DSCN9208.jpg

    DSCN9216.jpg
    ^ the black rectangular pieces with 3 solder joints are transistors

    Also used in the B1 are round, no-lead, MELF resistors, which is relatively unheard of for an amplifier in this price bracket (to my knowledge).
    More information here:
    https://en.wikipedia.org/wiki/Metal_electrode_leadless_face
    DSCN9306.jpg

    DSCN9294.jpg


    Although the overall aesthetics are really good, the build quality itself is a bit lacking to me. For one, the volume knob, which appears to be silver and suggests that it's made of metal like the chassis, is in fact plastic. The feel of the knob is very lame too. It's hard to grip, there are no volume indicators on it, and it seems to have variable resistance when turning (becoming easier and harder to turn depending on how far it's turned). It's definitely not the kind of quality I expected upon seeing it for the first time and it's underwhelming to adjust.
    DSCN9259.jpg

    DSCN9261.jpg


    The input/output ports of the B1 are poorly placed relative to the volume knob, especially with 90˚-angled jacks. Yeaaaaaaaaaaaaaaaaaah......good luck with that!
    DSCN9396.jpg

    DSCN9410.jpg
    ^ portable rig = ruined and unusable


    Just like the volume knob, the switches themselves are plastic and feel a bit cheap on the otherwise really nice chassis.
    DSCN9265.jpg

    DSCN9303.jpg

    DSCN9302.jpg


    The synthetic leather itself is just a sticker, and the edges are roughly cut upon closer inspection.
    DSCN9272.jpg


    Although the chassis is made of a single piece of aluminum, this aluminum also appears to be pretty soft. I don't recommend taking the B1 with you if it has the risk of falling onto a hard surface. I had the B1 on top of a piece of paper on my desk and the paper got moved by accident. *Thonk* The B1 fell on top of a glass table lamp I have nearby and the edges of the metal chassis got pretty banged up. The metal is now sharp at the edge and I am not going to stack anything scratch-sensitive on top, or underneath it. The glass lamp is fine though.
    DSCN9445.jpg

    DSCN9446.jpg

    : (


    Speaking of stacking things on top or below the B1 though, the package contents don't contain any adhesive rubber feet, nor silicone bands. Without those, you really have no viable options for stacking things on top or below the B1, which is unfortunate. The front face/top of the B1 is all aluminum with only the two glass windows. I ain't going to stack any metal or glass objects on top of that. On the back/bottom of the B1, it's basically all aluminum too with the synthetic leather inserts providing basically zero millimeters of padding between the B1 and the adjacent surface. I ain't going to stack any metal or glass objects underneath that either. For most of my time with the B1, I've been stacking the it on top of my OPPO HA-2 since the real-leather cover of that won't get easily damaged, and it provides some height to wrap my fingers around the volume knob to actually grip and turn it. I am most certainly not going to put the B1 in my pocket attached to a DAC/portable media player in fear of getting them scratched to death.
    DSCN9268.jpg



    As for the heat it gives off, it's really nothing worth mentioning, seriously. Yes, it's a Class A amplifier. Yes, it's extremely energy inefficient. No, the 40 mA current mode isn't going to get super hot. My iPhone 4S gets hotter than it when watching a YouTube video, so don't even worry about heat.


    Regarding power, the B1 might not have as much power output compared to other portable headphone amplifiers. However, I don't think power is really an important thing to use for a determination of sound quality unless you actually need 100+ mW for headphones. I used the 688 Ω AKG K240 Monitor, as measured by Innerfidelity for my specific unit, with the B1 on low-gain just fine. Taking into account my listening preferences, low-gain mode makes absolutely perfect sense for how I listen to music. It takes 0.447 Vrms at 688 Ω for my K240 Monitor to reach 90 dB SPL. My average listening volume is somewhere between 70-80 dB SPL as determined by a calibrated audio system from a local meet. I take into account +25 dB peak requirements from music as headroom for an amplifier, which makes the peak requirements 95-105 dB SPL. Indeed, calculating out the power requirements for the K240 Monitor, it would need 2.514 Vrms, 3.654 mA, or 9.184 mW to reach 105 dB SPL, all of which are perfectly within the B1's 3 Vrms output in low-gain mode as well as 20 mA Class A mode. For a low-impedance headphone that's relatively insensitive such as the HIFIMAN HE1000 on the other hand, the B1's limited current output starts to make the power output relevant since its cap is 40 mA.

    The gain switch affects voltage output; the Class A switch affects the current output. I find the low-gain output to have too much gain even still. I can barely use the volume knob for sensitive headphones like the OPPO PM-3, and I would say the volume knob is useless for in-ear earphones. I personally wouldn't recommend the B1 for these cases because it's simply just too loud. The volume knob has the typical channel imbalance at low levels, and then gradually diminishes as the knob is turned further. By the time I get past the channel imbalance region for the MEElectronics M9, even quiet music is too loud for me in a home environment. This is just unacceptable to me and it makes normal, non-quiet, music unlistenable at a comfortable volume level.


    Regarding the battery life, 9 hours for a portable headphone amplifier is on the low-side from what I've seen. If you're planning to use the B1 portable amp as a, well, portable amp, I would have liked to see at least 10 hours. Five hours in the 40 mA mode is even more of a setback, but I personally don't like the sound out of the 40 mA mode and I wouldn't use it anyway (more on this in the "Sound Quality" section below).

    Charging time for the B1 is also pretty slow. From 0-100%, I clocked in roughly 4 hours' worth of time while using a microUSB-USB A cable to my MacBook. That's a long time to charge a portable amplifier and if I want to use it as a portable amplifier, I would have liked to see a 2-3 hour charge time instead.

    While the B1 is charging, the device has an audible noise problem. It's audible with in-ear earphones, as well as full-size headphones like the HIFIMAN HE1000. It sounds like a fluttering/buzzing sound and it's pretty annoying. Trying it with different USB ports reveals that it's dependent on the connection. Through a normal USB-hub, the noise is audible even at low volume levels. Through my MacBook's USB ports, the noise is only audible when the volume knob is turned up. Through the LH Labs Linear Power Supply 4, the noise is pretty minimal. On high-gain, the noise is definitely amplified, no questions asked.


    In terms of its size, I think the B1 is way too thick to be consider portable, hence why I have "Portable" in quotes for my review title. It's nearly as thick as my Nintendo 3DS handheld gaming console and I already consider that to be a huge burden to carry around in my pocket since it's also smartphone-sized in terms of length and width. Carrying around a Nintendo 3DS-sized metal brick on top of a portable media player or other source prevents the B1 from being portable in my honest opinion. To me, it's more transportable than portable.
    DSCN9233.jpg

    DSCN9429.jpg

    DSCN9438.jpg





    So...yeah, the build quality and some of the design elements are things to be desired in my opinion, hence why I gave the Quality and Design ratings 3.5/5 and 3/5 respectively. It's good enough for the job, but I feel that a lot of things could be improved upon for future consideration.



    [rule]
    Overall, the B1 sounds pretty good to me! There are two things main things about the B1's sound that I experienced:
    1. I prefer the sound from the 20 mA mode over that of the 40 mA mode
    2. It compares favourably next to other portable and transportable amps I have at hand

    An overview of how the B1 in general sounds to me:
    • Slightly woolly-sounding bass
    • Slight warmth in the bass/lower-midrange area
    • Slight etch or emphasis in the upper-upper-midrange area (4-6 kHz-ish)
    • Treble roll-off
    • Wider-than-deep soundstage
    • Good, but not great, instrument separation
    • No background hiss

    Again, these impressions are all with the low-gain mode because I find low-gain to offer plenty of voltage for my listening preferences, let alone usage of the volume knob.

    I did a ton of listening sessions between the 20 mA and 40 mA modes. At first, I hardly heard a difference between the two modes. I was thinking maybe the 40 mA mode had a larger soundstage, but I would be pulling strings to say I would be able to pass a blind test with it. Those listening tests were done with just a DAC and the B1. Aune specifically recommends not adjusting the current switch when the B1 is in operation, so I would listen to the B1 in one mode, turn it off, switch the Class A switch, and turn it back on. The time it took to do that process probably skewed the results.

    I later did A/B tests against other amplifiers while using the FiiO HS2 as a switch and I was able to more reliably, and accurately, hear a difference between the two modes. In summary:
    20 mA mode:
    • Slight warmth in the bass/lower-midrange area
    • Wide soundstage, little depth
    • Decent center imaging

    40 mA mode:
    • More warmth, and a slight sub-bass boost
    • Wider soundstage, more depth
    • Lack of center imaging

    It is because of the better center imaging that I prefer the 20 mA mode over the 40 mA one. The 40 mA mode reminds me of the AKG K 701's infamous soundstage and imaging abilities: much wider-than-deep soundstage and a lack of a center image. It just sounds plain weird to me. However, you may prefer that kind of sound, so your mileage may vary.

    Were I to blind test the 20 mA and 40 mA modes now that I have a better understanding of how they sound with an A/B switch, I'm pretty confident I would be able to pass it just because the weird center imaging of the 40 mA mode was so strange-sounding to me.



    Now, against other portable headphone amplifiers I have at hand, the B1 stacks up pretty well against them. All of these tests were volume-matched by ear with pink noise and 1 kHz sine wave signals generated from Audacity. I toggled between the 40 mA and 20 mA modes for these tests too, so the following impressions are more or less an average of what I heard. I still prefer the 20 mA mode though.
    DSCN9383.jpg

    Setup:
    • MacBook Pro + Audirvana Plus 1.5.12 (hog mode, integer mode, no upsampling)
    • LH Labs Linear Power Supply 4 for a clean USB power source
    • Objective DAC + RCA outputs
    • Y-splitter to go into two amplifiers
    • B1 and other amplifier to compare to
    • Outputs of amplifiers to HS2
    • Headphone of choice

    Headphone of choice included any of the following, and I did tests with all of them for each amp comparison:
    • AKG K240 Monitor (high impedance, low sensitivity, voltage-demanding)
    • AKG K701 (medium impedance, low sensitivity, current-demanding)
    • HIFIMAN HE1000 (low-impedance, low sensitivity, current-demanding)
    • OPPO PM-3 (low-impedance, high sensitivity, current-demanding)

    FiiO E12 (~$129 USD) vs B1:
    • E12 sounds grainier
    • E12 sounds much brighter and harsh
    • E12's bass sounds more woolly
    • E12's soundstage seems much more narrow in width
    • E12's instrument separation is much more blurred
    Hands down I would pick the B1 over the E12, no questions asked.

    JDS Labs Objective 2 ($130) vs B1:
    • O2 sounds smoother
    • O2 has better treble extension
    • O2 has better bass control
    • O2 doesn't have upper-upper-midrange emphasis
    • O2's soundstage is more rounded overall
    • O2 has more rounded imaging abilities
    • O2 has better instrument separation
    It's a tough call for me. I do like the B1's wider soundstage since it gives the illusion of a larger room in width, but I think the O2 would technically be a better amp sonically overall.

    JDS Labs C5 ($189) (in my case I used the C5D since it has a lower output impedance from my older C5 unit, but the amplifier is exactly the same other than the bass boost switch which I didn't toggle) vs B1:
    • C5 sounds slightly smoother
    • C5 has better treble extension
    • C5 has better bass control
    • C5 sounds brighter in the typical 2-4 kHz area versus the 4-6 kHz region of the B1
    • C5's soundstage is more limited in width
    • C5's center imaging is much better
    • C5 has better instrument separation
    Again, it's a tough call for me. I might give the B1 a slight upper-hand here because it doesn't have the bright sound of the C5, but at the same time, I do like the C5's instrument separation and center imaging more.

    OPPO HA-2 ($299) (keep in mind that this is a DAC and amp, so you get more for your money there) vs B1:
    • HA-2 has better bass control
    • HA-2 has better treble extension
    • HA-2 has better instrument separation
    This was by far the hardest test for me. On the 20 mA mode, the two sounded basically identical to me. The B1 might have had a little more warmth, but it was really hard to hear reliably. I give the upper-hand to the HA-2 in this case due to the better treble extension on the other hand.


    All in all, this was a pretty interesting testing session. It's been commonly accepted that Class A amplifiers "sound the best" amongst amplifier classes. This may be true, or may not be true. The design of the amplifier is of the most importance to me though, not the class. Obviously I think the O2 overall sounds better than the B1 in a technical sense, and the O2 is a Class D amplifier that uses operational amplifiers. The OPPO HA-2 sounded nearly identical to the B1 and it uses a Class AB architecture.



    [rule]
    Pros:
    • Great sound
    • Unique internal design of discrete components and Class A architecture
    • Class A switch might be worth experimenting with for various headphones
    • Excellent voltage output
    • Fairly competitive price

    Cons:
    • Slightly low battery life
    • Disappointing, but overall okay build quality
    • Some pretty important design flaws that could be remedied

    A thumbs up from me for sound quality by itself at its price point, but a thumbs down for practical use (as a portable device) and overall shortcomings of the design and build quality.



    Thank you again to Aune for letting me have this opportunity to listen to the B1 with my own setup for these past two weeks. It's been a fun learning experience for me and I look forward to seeing what products you release in the future!

    As always, thank you for taking the time to peruse through my review and I hope you got a thing or two out of it.


    DSCN9419.jpg
    1. View previous replies...
    2. Peter West
      Don't know where my last message came from re text editor...sorry about that...

      I'm reviewing the B1 right now and I'll post in a couple of days. We may have to agree to disagree on some points. The B1 really makes my LCD-X come alive especially when compared to my more laid back Picollo amp. Haven't got to testing out my in-ears yet. So far I'm very impressed.
      Peter West, Jun 26, 2015
    3. miceblue
      That's why we have multiple reviews for a product!
      I tried to make my review as objective as possible without directly measuring anything, and I made numerous comparisons between other amps and other headphones of varying impedances and sensitivities with those amps.
      miceblue, Jun 27, 2015
    4. hqssui
      Excellent review . Thanks a lot..
      hqssui, Aug 11, 2016