Aune B1S

Build Quality:
I can probably think of maybe 5 companies that comes close to Aune's well thoughout build quality.
Absolute beauty. This is not something that you put inside you pocket and forget about. this is something
you keep looking at it until it burns from eye beams. I talk about each aspect of why I like it so much in the video.

Sound Quality:
have you ever eaten out at an all you can eat and was so full that you were about to vomit but you just had to
keep going because it was so good and you wanted more of whatever sensation you were getting?
Thats what feels like to own and hear through the B1s. Of course, it does have flaws and shortcomings
like all devices. But at this price point?
I go into each aspect of why I like the sound so much in the video.

Intro:
I recently had the opportunity to audition the Aune B1s amp. Thanks to a tour that @MSheney put together. I had the Aune along with a number of other amps over the Easter holiday. I plan to write up a whole Easter Amp Shootout thread, but for now, I’m just going to discuss the Aune B1s.


Equipment and Methodology:
Let me talk a little bit about the usual suspects, and my methodology. I used a Shanling M2s in Line Out mode. The Aune B1s in Class A – High gain mode. My music is FLAC L5 16/44 accurate rip from my own CDs. The headphones I used for the shootout were the AKG 702 – Austrian version (stock), LCD-XC with WyWires Red Cable, and a stock Fostex TH-900 v1. I evaluated 3 songs from the same album. From Steely Dan’s “Can’t Buy a Thrill” album, I listened to the first three cuts. “Do it Again.” “Dirty Work.” “Kings.”


I used a TACKlife SLM01 Sound Level Meter to try to level adjust as closely as I could. In the song Do it Again, I used the 2nd Verse as my standard. I used the left ear cup for each headphone and I leveled as closely to 80 dBA peak as I could. Starting around 1:55 seconds into the song is where the 2nd verse starts. The instruments and vocals tend to culminate with a peak around the words “Climber” and “Timer” in the second verse. I tried to get those two areas to hit between 80 dBA and 81 dBA peak. This allowed most of the songs energy to live in the 70-75 dBA range with it not peaking much over 81 dBA.

Now three songs may not sound like much of an evaluation, but those 3 songs total over 13 minutes of music. Add into that level setting for four amps and three headphones and this eval lasted around 5 and a half hours for all amps and headphones. I have to admit, by the time I was done, I was exhausted and really tired of hearing the same 3 songs over and over again. But I did learn some things by listening closely to those songs over and over and over and over and over…

B1s and TH-900 Synergy:
The first thing I would like to say about the Aune B1s is that the engineers must have a pair of Foxtex Th-900 in the lab. This was a truly incredible pairing and terrific synergy. The TH-900 have the reputation for having recessed mids and strident highs. With the Aune B1s, I found that it brought the mids forward and was nice on the top end. While listening to the solo for Steely Dan’s “Do It Again” I felt that the B1s provided a wonderfully full presentation with all the instruments presenting exactly where they were supposed to be.

On the day I had to ship it out, I spent the entire morning listening to the Aune B1s & Fostex TH-900 with Elton John’s Madman Across the Water and Goodbye Yellow Brick road. I have to say that I was sad to have to box it up and send it away.



Other Headphones:
“What about the other headphones mentioned,” you ask. Well, I have to say that I did not love the pairing with the AKG 702 and the Audeze LCD-XC. I felt that it was lacking in energy and heft with those two headphones. At this time, I’m just going to have to chalk it up to my preferences and I would need to spend more time with the Aune B1s and other headphones and different music. The experiment I conducted on Easter was a little limited due to the sheer number of amps and headphones I cycled through. So I can’t really want to say anything disparaging about the B1s.



Physical Attributes:
The Aune B1s is an extremely solid piece of equipment. And the window looking in at the components is a very nice touch. If anyone asked my opinion, I would suggest a different volume knob. I don’t feel like the current knob pays justice to the rest of the amp. The knob feels like plastic to me, and I sometimes had problems gripping and adjusting the volume. A nice knurled metal knob would knock the physical aspects out of the park. But that is just a small comment on a fantastically built amp.

Conclusion:
If you get a chance to try out the Aune B1s, definitely do. With my TH-900, it sounded simply sublime. I know that this is a good amp and depending on the situation, can sound wonderful. As always, this is my opinion and everyone hears differently. So go and try the Aune B1s for yourself.

Quick Read Conclusion

The Aune B1s ("B1s") is a head turning pocket amplifier very well suited to more sensitive headphones, including IEMs that benefit from a little more oomph and a low noise floor. Although it makes a lovely, warm sound it is hard to recommend without question because it suffers from mobile phone interference, and does not drive that loud. An IEM only amplifier is a niche offering!

Introductions and General Bumf

Test Kit: I have tested the B1s with Shure SE215, SE425, Sennheiser HD600, Ultimate Ears UE900s, Campfire Audio Polaris and KEF M500 headphones/IEMs. As input sources, I hooked the B1s up to a Schiit Modi 2, iFi iDSD Nano BL, Samsung Galaxy S8, Note 8, Pioneer XDP-30r and an Astell and Kern AK70.



Preparation: I did not give the B1s any burn it, but as I was about the fifth person on the tour to use it, I figure it should have had a decent burn in by the time it got to me. It gets reasonably warm in operation, so I always gave it an hour or so to warm up before trying to listen critically.

Me as a listener: I am not a pro by any stretch of the imagination. I have always enjoyed my music, and my tastes are pretty broad. I go to live music ranging from rock and pop concerts to orchestra and opera. I would not describe myself as having a trained ear, but I am attentive and my ears are in pretty good nick for a 34 year old.

My tastes: neutral to warm, but I do like good punchy bass and I love to hear decent instrument separation.

Test tracks: I've tried to keep it broad and I have cited my music sources below, so (where possible) people can download the tracks themselves.

1) Wiz Kalifah – On My Level (320k MP3, Google Store)

2) Norah Jones – Turn Me On (24/192 FLAC, Qobuz)

3) John Williams – Throne Room from Star Wars performed by Prague Philharmonic Orchestra (16/44.1 FLAC, Qobuz)

4) The Verve – The Drugs Don’t Work (16/44.1 self-ripped FLAC)

5) Ed Sheeran – Castle on the Hill (320k MP3, Google Store)

6) JS Bach – Brandenberg Concertos, 1 (allegro) (16/44.1, self-ripped FLAC)

7) Hilltop Hoods ft. Sia – I Love It (256k m4a, iTunes)

8) 30 Seconds to Mars – Stronger (Radio 1 Live Lounge Cover) (16/44.1, self-ripped FLAC)

9) Pearl Jam – Yellow Ledbetter (320k MP3, Google Store)

10) Rage Against the Machine – Wake Up (292k m4a, iTunes)

Disclaimer: The B1s was temporarily provided to me for review, as part of the European tour organised by @tenedosian. I am in no way affiliated with Aune and have received no inducement to provide this review (other than the chance to participate in the tour).

So, on to the main event. [/General Bumf]

Unboxing

This is another premium experience. Well packaged in good quality, thick card, the Aune B1s is an absolute treat to open. From popping off the lid, you are greeted by a warranty cards and instruction card, followed by the amplifier itself (packed in matte effect plastic covering). The box I received had already been opened and as a result, the included 3.5mm male to male cable, usb charging cable and rubber rings were sent to me in a separate bag. I presume in the original retail boxing, these are packaged below the main unit.



I didn’t bother with the included 3.5mm cable, much preferring a sturdier Fiio cable I bought myself on amazon a while ago. In particular, the included cable fouled on the covers to my mobile phones whereas my Fiio cable does not. I also particularly liked the charging cable – it was a well manufactured cable, with gold coloured (presumably gold plated?) connectors. Given these are not intended to carry data to the unit, only power on recharging, this seemed an unnecessary but aesthetically pleasing addition.


mmmmmm golden

Practicalities

My measurements, match those on the Aune website (125x65x18). That makes the B1s sort of chunky iPhone SE sized! The biggest to say though, is that the finish on this thing is absolutely beautiful. Reminiscent of the Continental dual mono (including the light up side by side windows to the internal electronics – lit by LEDs in the B1s rather than valves in the much more expensive Continental amp) the brushed, anodised all metal exterior and (in my test unit, black) pu leather on the rear of the unit create a real high quality feel.


So what if I'm a magpie. Shiny impresses me!


The back is beautifully tactile

The satisfyingly solid switches to the sides of the B1s also add to this, and the only criticism of materials I have is that the conveniently wedge-edged circular volume control is made from a cheaper feeling plastic than anything else on the B1s. As this is the part of the B1s you touch the most, one would have thought Aune might have gone knurled aluminium or similar – but this is splitting hairs on an otherwise beautifully built piece of kit.


A focus on that average volume wheel, but did I mention it's shiny?

It feels solid in the hand, and is a real eye catcher. I had more questions about this unit in my office than just about any other piece of audio kit I have had in there… perhaps because of those shiny front LEDs and window panels.

On the top of the B1s are the 3.5mm in and out sockets and that volume control. Worth noting here, that that 3.5mm output is single ended only, and the B1s has no ability to drive headphones in a balanced configuration. To the left side from the front, the gain, voltage and power switches, to the right (from the front) the slightly weird battery charge indicator light (which gives a number of flashes to indicate charge rather than a more customary red, yellow green set up) and button, and on the base the micro usb charging port.



In my test the unit took around 5 hours to charge from a normal phone USB charger, and I was getting 6-8 hours of playback depending on what headphones (and volume) I was using. So battery life is about 1 day of normal use for me, which is fine, but if you buy a B1s you will also need to ensure you don’t stray too far from a wall socket if you will be using it more heavily.

So then, on to the first of my two main criticisms of the B1s. RF interference. It wasn’t until I took the B1s on a train trip with me, having forgotten to charge my AK70. As the DAP died, I thought the time was perfect for having a play with the B1s hooked up to my phones. Unfortunately, the results were a little disappointing. Whilst the sound quality and amplification were in line with comments further below, there was the noticeable click and buzz of mobile phone interference. I tried a few tricks to resolve, but found that turning off 4g data was the only solution. Which meant no Tidal. I suspect the majority of people who will be purchasing a B1s will be doing so to use alongside a mobile phone (see criticism 2 below) and hence I think this is a material issue for anyone who wants to stream music on the move.

And the second criticism? Volume. This is an amplifier, but it does not amplify that loudly. Whilst it does a good job of amplifying the output of a mobile phone, and pushes well beyond comfortable volumes when driving IEMs, it simply did not drive my HD600s to unlistenable levels. I cannot therefore recommend this for anybody with low sensitivity cans. This said, there is a plus here, which is sweet, sweet silence. On maximum voltage, gain and volume there was no audible hiss from any of my IEMs (including the CA Polaris, which tends to be less sympathetic than my other IEMs). So an amplifier for IEMs perhaps?

The Sound, Comparisons and Matching

As this is an amplifier, I haven’t done the standard highs-mids-lows review. Ultimately, this is an amplifier and so should just be making the existing signal louder. It undoubtedly helps some kit perform a bit better – the Shure SE425s for example, I always think sound better amplified, and the B1s drove them well, creating that wider feeling and greater clarity which the SE425s only deliver under amplification.

This said, there is a definite colouration of sound from the B1s, placing a greater emphasis on mids and low mids, and delivering a warmer sound. I have seen reviews which compare the B1s to valve amps, and compared to my Vali 2 (with the stock Schiit tubes), it sounds good – warmer than the Vali, with a greater emphasis provided on (especially male) vocals.

The net effect of all this, is that I found the B1s a little picky with headphones, especially when running from a source which has a lean to the warm anyway, like the Nano iDSD BL. With the Shure SE425s and to a lesser extent the Kef M500s, mids swamped out both the bass and the treble, resulting in a harsh almost shouting quality to music that I have not heard before. This was most evident on Yellow Ledbetter on the 425s, with guitars lost in the background and the soft vocal jarring in my ears.


Too long a chain to sensibly be mobile, but it did sound good.

In complete comparison though, the B1s sounded great with the CA Polaris, which is a little light in the low mid range. This was a dream pairing, sounding airy and clear on every track I listened to, but (from my phones and XDP-30r particularly) bringing the voices of Ed Sheeran, Bruno Mars and Frank Turner back to the front of the recording. It also sounded very good with the HD600s, where I heard a noticeable clarity and separation compared to other sources, especially my phones.


The CA Polaris and B1s played together very nicely. So well, I'm seriously considering buying a B1s just for the Polaris.

Other thoughts

The problem is, I just don’t get who buys a B1s as their first foray into mobile amplification…if you want pure amplification, the Nano BL and the XDP-30r and AK70 (esp. in balanced mode) drive louder, and there are any number of more versatile DAC/Amps in a similar price band that provide more amplification and do the DAC stuff. But don’t get me wrong – I want one. It is beautiful, it lights up and it does make a satisfying noise, especially with my CA Polaris.

Finally, one more thing I knew I would missing when sending the B1s on for the next leg of its tour. When you switch the B1s on, there is obviously some sort of reed switch circuit performing some internal sorcery. For the first second or so on turning on the B1s, it does nothing but light up – then you hear (and feel if you are holding the unit) a solid and thoroughly satisfying click as the reed switched circuit is engaged. It sounds and feels like an old valve amp clicking on. Puerile exuberance ensues. Honestly, it is beautiful, and adds to that quality feel that the B1s constantly exudes.

Conclusion

Plain and simple, I want one. It makes my CA Polaris sound even lovelier, looks great and oozes "quality product". Well matched, with the right IEMs, this is a wonderful amplifier, but the low power output and electrical interference move this from 5 stars to 4 for me.

It’s funny how coincidences happen. Almost 2 years to the day I reviewed the original portable amp from Aune, the B1. And if you’ve seen or even read my review, I’m pretty sure I got across that I rather enjoyed the little guy. So to be able to try out its successor made me, needless to say, very excited. But of course I must give my humble thanks and appreciation to both Aune for providing a unit for me to review, and fellow head-fi’er/reviewer MShenay for organising the tour and for allowing me to take part. So to you my friends, again, I give you my sincerest thanks. But with the pleasantries aside, please allow me to now share my thoughts on Aune’s portable headphone amp, the B1s.





The Opening Experience




The handshake that Aune gave me with their B1s was, overall, satisfactory. The box that came with my review unit was exactly what I personally like seeing. It was just a very simple box that only have Aune’s name on the front and some very generalized writing on the back. As I said in the unboxing video I’m not sure if the full retail version of this will have like a cover to the box that has anything else on it but I personally think this is exactly what you get as a consumer. When you open the box you’re greeted with 2 separate compartments that don’t focus a lot on looks over simple delivery functionality. The first compartment holds the beautiful Aune B1s and the warranty & owners manual, while the other holding the micro USB charging cable and a 3.5mm to 3.5mm aux interconnect cable.

So nothing really set the Aune B1s apart from any other portable amp’s or combi’s that I’ve tried and I’ll very likely forget about this unboxing, but I will say that I wasn’t disappointed at all either, it’s just a normal unboxing experience.


Construction




Aune continues to deliver quality build products within a very reasonable price. Their newest B1s portable amp. is made almost entirely out of aluminum minus some faux leather accents on the back. But the top of the B1s contains a 3.5mm headphone input, the really smooth and linear volume control knob, and the 3.5mm aux input. The right side of the B1s (if you’re looking at the front has the battery indicator light (simple enough) that I personally don’t like how Aune does it, but I’ll discuss that more in depth in the features section.

The left side of the unit (going from top to bottom) has the gain switch, current switch, and power switch. The bottom of the B1s has the micro USB charging port. The front and back of the B1s is super simple with only 2 panes of class showing the viewer the inner workings of the amp and the back, as mentioned earlier, has 2 faux leather accents.

I really don’t have any complaints but rather nothing but satisfaction and joy with the build of the B1s. It’s constructed very well and, though I haven’t personally tested this, I’m quite confident that it’ll survive a respectable fall and not skip a beat. Aune also paid mind to the size and I was very easily able to carry this without trouble in my laptop bag I took to work or in my pocket with my phone (I did need to use bigger pockets for this though, i.e. shorts or sweatpants) and wanted to jam as I shopped for groceries. So well done Aune


Features


For the most part the Aune B1s is a very straightforward portable amp. But there are two features that I would like to give special mind to. The first is the current switch. Aune implements a current switch that’s separate from the gain switch. This allows the B1s to be much more versatile in the products it can drive and, what I believe, gives it the ability to play so quietly with hyper sensitive c/iems. Now, please keep in mind that if you’re rocking high gain AND high current then the battery of the B1s will die quite rapidly. The 5 hours Aune claims on their site is quite close with ME PERSONALLY getting roughly 4.5ish hours when driving my higher impedance cans. And this little booger does live up to the class A name for it will also get a little toasty, nothing to cause worry or honestly even discomfort if being held, but certainly warmer than any portable amp I’ve personally held.

The second feature the B1s has is its battery indicator light, that I’ll be right up front in saying I really don’t like. Call me old fashioned or what have you but when I see a single indicator light that determines how much battery a product has left I like seeing it change from green to yellow and then to red. But in the case of the B1s they chose to go with blinks. As I was writing this review the battery of the B1s went out and when I clicked the indicator light expecting to see a red light I was greeted with a green blink. Quite perplexed I looked into the manual and it states that there’s 5 patterns the Aune B1s shows in relation to battery life.



1 flash indicates the B1s is at 10% of its battery or less

2 flashes indicate it’s between 10 and 20%

3 flashes indicate it’s between 20 and 60%

4 flashes indicate it’s between 60 and 80%

5 flashes indicate it’s between 80 and 100%


Now granted, I did not look through the manual before I played this product and if I did I would’ve known that it does this, but I still don’t personally like it.


Sound



To jump right into my thoughts on how the Aune B1s sounds, I really liked it. The B1s, to my ears, added a very nice touch of warmth and vocal forwardness that didn’t alter the overall sound of the headphones very much but it just added that little bit of sauce to add a touch more musicality to the notes. The most impressive results of this I got was on the Meze 99 Classics. My goodness did these two pair beautifully together and similar results were had with the Sennheiser HD660 S. Being completely honest, the B1s didn’t “open up” any of the headphones I listened to or make any sort of drastic improvement but that touch of warmth and musicality it gives the headphone is something that I really, and let me stress, really relished in during my short time with it. If I had to put my finger on a description of the B1s’ sound, it would be like adding tube like sound to a solid state amp.

The power to drive headphones is fairly respectable so long as nothing you’re not wanting to power anything too difficult. The B1s, on high gain and high current can drive, from my headphones I tried listed above, headphones from the HD660 S and below really nicely and with impressive results. However, when you move into more difficult headphones (in relation to the rest of what I was using) you definitely reach the upper ends of what the B1s can do. The website specifically mentions the Sennheiser HD650 in its product page so I made it a point to test mine with it to hear the results. So, yeah, it powers the HD650 with respectable vigor, but to my ears there’s definitely a lot more than the HD650 can put out and I won’t even start on the HD800 S. In terms of volume the B1s gave each of the two aforementioned headphones plenty of that for my ears to be able to listen to comfortable but there was most certainly more potential to be had in both headphones.

To my BIGGEST surprise and enjoyment, the Aune B1s played DEAD SILENT to my hyper sensitive Empire Ears Hermes VI ciems. I heard nothing remotely close to a buzz or jitter through them which is a major testament to the B1s because I’ve listened to combi’s and DAP’s that costs considerably more than this $230ish and there’s only a VERY small select few of them that have a background and noise floor as silent as the B1s presents. So Aune, you all have done a very nice job with your B1s.


Conclusion




My final thoughts on the Aune B1s is that I really enjoy the ‘tube like sound’ they give their solid state portable amp. The touch of warmth is something I personally greatly enjoyed and will miss having this really attractive piece strapped to my phone and laying back in my chair on in my bed just finding new enjoyment in music. It’s built very well and I’m conifdent that whoever purchases one of these, so long as they take reasonable care of it, will last them indefinitely. I do wish however, that the B1s had more power so that it really could drive more difficult headphones other than my reasonably portable ones, but for the majority of my collection it definitely sufficed.






Also, make sure to check out my unboxing and review videos. They’re pretty awesome AND you getta put a face to the Army-Firedawg name. If this review helped you out at all please hit that thumbs up button for it really helps me out a lot. Till next time my friends, stay safe.

Thanks for Aune for offering this tour to the community and @MSheney for organizing the tour.

Unboxing

The Aune B1s comes in a black pressboard box with the name Aune emblazoned in Silver on the top, and the name and address on the bottom. No details about what the box contains are displayed on the packaging as is typical of Chinese packaging meant for eastern markets. It certainly is not packaged in such a way to be sold in the average US based electronics store. On the inside of the box, a simple cardboard insert separates the interior into a compartment for the Amp and a 2nd smaller compartment for the cables. Cables are a heavy gauge roughly 3 foot USB to micro-USB cable, and a meager 3.5 TRS interconnect. Hiding under the cardboard are a set of rubber bands for connecting the amp to a phone or source.


Build Quality


The amp itself is roughly the same size as a standard cell phone in height and width and about ¾ of an inch thick. The front face contains two parallel cutouts in the aluminum case to show some of the circuitry. This move was very deliberate to show the discrete circuity inside the amp as most of the competitors at or near this price point rely on integrated circuit op-amps rather than using a fully discrete design. Use of an IC is both a space saving and power saving measure but can be seen by some as cutting corners. The plastic used to cover the windows is slightly flexible and somewhat susceptible to scratches as a few small ones are already present on the tour unit. The remainder of the unit is solid aluminum with no screws visible at all in the construction. The rear face has two inset red synthetic leather strips that run most of the length of the player and create a good gripping surface. The left side has three sliding buttons. The power button is slightly below the middle of the unit, with the class A button next in line and the gain button nearest the top. On the right side, a single push button is used to show battery reserve. At the top of the player, a 3.5mm line in jack sits on the left, the volume knob is centered in the middle and the 3.5mm single ended headphone out jack is on the right side. One nice touch that I think is omitted on way too many products is a mark on the dial and a + and – mark on the unit to show increase/decrease of volume at a glance. At the bottom of the player is a single micro-USB charging port.


Buttons

The buttons are well done. Very positive and tactile. The top and bottom form rails that partially recess the buttons on the left side while the right-hand button is flush with the surface of the player. The elephant in the room though is the Class A button on the middle left. Aune’s documentation says never to move that switch while the player is powered on or it will damage the amp and possible things attached to it. Why you would place that button between two others that do not have the same requirements and not put any safety mechanism that prevented an accidental movement is beyond comprehension. That alone takes this player out of the ranks of pocket amps for me and places it in the sits on my desk at work category, problem being they recommend not using it while charging either, which takes it back out of the sits on my desk at work category and leaves it in limbo. On the next iteration, I would recommend that Aune use a recessed style button like Fiio did for the e7 and e17 lock functions that requires the point of a pen or key to engage.



Volume/Class/and Gain

The B1s has a rare ability to fulfill both the IEM amp niche and the I want to use my 600Ohm Beyers on the plane niche. With the gain on low and the current on 10ma, the B1s has a low enough noise floor to be usable with sensitive IEMs like the Magaosi K5 that can have problems with hiss. The volume knob has a larger travel than many portable amps and gives very good granularity of control so finding a comfortable playback level is an easy task. In this respect, Aune nailed what Fiio attempted to do in redesigning the E12. Arguably Fiio did well with the E12a on that end of the spectrum but struggled on the other end where it failed to drive low sensitivity cans with any authority. The B1s gain switch alone is enough to provide power to full sized headphones. It should be noted that flipping the gain switch with iems in your ears is very likely to cause brain damage and ear drum rupture when using the B1s as the gain goes from very mild to through the roof when you flip the switch. (Ok, so maybe brain damage is a bit of an exaggeration but the gain difference is exponential). For really hard to drive stuff like the Fostex planars, the Class A switch can be flipped (with the unit turned off of course) to double the current. This allows the B1s to fully drive some really tough cans. Flipping the current switch will ½ the battery life and generate quite a bit more heat. I never felt that the unit was hot enough to be uncomfortable to hold, but the difference in heat production is noticeable.



Sound


When I first saw the specs on the B1s, I had some preconceived ideas of what it should sound like but I was conflicted. Some of what I was thinking of was typical Tube based class A amps. Warm, thick, maybe even a little syrupy, but this was a solid-state amp, so I thought maybe a bit dry and clinical. What I got when I listened to it was somewhere in between in some respects and completely unexpected in other aspects. The hard aspect of reviewing an amp is finding those things the amp brings to the table and not attributing characteristics of the rest of the chain to the amp. Clarity, detail, and speed were exactly what I had expected from a solid-state amp and were all very good. That was the easy part. Getting a firm grasp of the sound signature took a good bit longer. After listening with several different headphones, I came away with impression that the B1s is slightly bright and decidedly mid forward.


Starting with the mids since they are the focal point here, I found the upper mids to be forward of the rest of the signature. Most of the time this was only slightly noticeable, but on simple tracks with only a piano and vocal or acoustic guitar and vocal it could get mildly fatiguing. A little volume adjustment was enough to prevent fatigue, but that wouldn’t be needed if the response was entirely flat. The treble is slightly overly-energetic which leads to mild brightening of the signature. At times, this is very much welcome as it complements the typical Sennheiser house sound well, at other times not so much. On the Grado 325 that is already a bit mid heavy and bright, the B1s is enough to push it into unwelcome territory. The biggest caveat to the B1s is that pairing it with a headphone that already has forward mids is going to result in extremely forward mids. For a few, this may be exactly what they are hoping for, for most of us, this will be an unwelcome combination.

Good pairings for me were the Fostex TRP50, the Sennheiser 650 and 700, the Beyer 990, and the AKG n40. Yep, I included an IEM. On low gain, the B1s does a very good job with them and the noise floor is still jet black. On high gain, the AKG n40 would result in ear-splitting volume at anything over about 1/8 of the travel of the volume knob and a moderate hiss is present with the volume knob at zero.

Instrument separation is quite good. Soundstage leaves me a little conflicted. I really tried hard to discount this observation as a function of the sources I was using, but ultimately found that rolling through an Opus #1s, a Cayin N3, a Shanling, a Fiio, and an Essence sound card, I ended up proving what I was trying to eliminate. I found that the B1s does distort the soundstage in that the stage was wider than it was deep regardless of which source was being used. That is not the natural tendency of a couple of those sources so when I found the same effect coming from two that normally have good depth, I couldn’t ignore it. The more I traded sources, the more I noticed that regardless of source, the B1s projects a very similar soundstage. At times this is a good thing, at others, that distortion causes an unnatural positioning of instruments on the stage and can play some games with the imaging.



Overall

I find the B1s to be a very good portable amplifier that is somewhat particular about the source and headphone pairings it needs to do its best work. Darker signatures will benefit from the mid-centric nature of the B1, and choosing a source that pairs well with the B1s tendency to reshape the sound stage will help with imaging. Of my gear, I would pair the B1s to the Fiio X3 as the source as it was the least impacted by the shift in soundstage, and the Sennheiser 6xx as the mid-forward slightly bright nature of the Aune B1s complements them extremely well. In the next generation, if Aune would add a balanced input and output capability and put a mechanical lock of some sort on the current switch, I would like it even better.

Aune is a Chinese company known for its minimal and sleek designed audio gear with a focus on high fidelity sound at a reasonable price. The aune B1s is the first overall upgrade of the well acclaimed aune B1. One of the best value in budget amps.

The aune B1s has been lent to me by @ethosian on the case of a sponsored European tour. I have tested the amplifier for about week. I'll try to be as accurate and objective as my ears and my brain let me to be.



#SPECIFICATIONS:

• Typical line output indicators
• Frequency response (from 10 Hz to 20 kHz): ±0.02dB
• THD + n: 0.00015% @300Ω
• SNR: 124dB @300Ω
• Crosstalk: <110dB @300Ω
• Max output: 6.443Vrms 18.4dBu(10Hz to 20kHz)
• Headphone output power: @300Ω 84mW , @600Ω 42mW ,@32Ω 74mW
• Class-A: 25mW/16R 50mW/32R
• Size: 125×65×18（mm）
• Weight:230g

• Output impedance: c.1ohm

#PACKAGING AND ACCESSORIES
The aune B1s comes in a black box with a thick usb cable and a humble 3.5 to 3.5 interconnect. So me manuals in Chinese and English. No need for more.

#BUILD
The B1s has the dimensions of a 5" smartphone except it's a bit thicker. It is too big to fit my jeans pocket but it's small enough to be in a jacket or coat pocket. It's a bit heavy, I wouldn't like to drop this thing considering it has a glass panel. The volume knob is made of high quality plastic. The chassis is of brushed metal glued to what looks like aluminum on a side and leather on the other. There is a small led button to check battery life.
The knob has large travel and it's really easy to fine tune the volume desired. I noticed channel imbalance at very low volume but nothing alarming considering the quality of the low gain.
There is two gain modes. The low gain is quite conservative and you can easily use sensitive earphones without hassle. The high gain has power and I only need to go as far as 20% to get comfortable volume with my 300 to 600 ohm earbuds. The amp can get rather warm. Slightly more than lukewarm. At the time of the review, it is very cold in Europe right now, But I would assume, in summer or in a tropical area, this may be uncomfortable for some.
I don't know how easy it is to open it but I guess you'll have to tear down some panels considering I couldn't find any screw. I guess it is not meant to be eventually repairable or modded. Something that concern me considering the battery life is on the short side (c. 8 hours on CLASS A). If used on a regular basis, I don't know how well it will pass the two years mark.(average life of a lithium battery before it start to degrade significantly)


airy, smooth, clear like the Swiss mountains on a sunny day

For the review I will mostly use the nuansa P1 (Philips multibit DAC TDA1387T) as a source with a jensen silver cable with oyaide plug interconnect. I will also do some test with the Zishan Z2(AK4490 DAC)

#SOUND
earphones used: Puresounds PS100-600, K's 300 samsara, SeaHF F650S, Blur black cable.
Coming from the aune m1s, I felt at home with the aune B1s sound, It's quite airy and clear. The imaging is accurate. Compared to the m1s, the sound stage is larger, the treble more controlled and overall it sounds more musical. There is a holographic-like presentation, It's easy to sense the space of the scene. The sub bass is of excellent quality, and can reach low with the right earphones. The sound is airy, It has an holographic quality, the layering and separation is excellent. It's very resolving and textures are rich. Overall the tonality sounds right to me. There is a slight upper mid lift which gives an overall sense of clarity.
The sound signature of this amp could be described as an "airy and fresh" for the lack of better term, If you are happy with the aune M1S, you couldn't be more satisfied with the B1s.
Although it sounds excellent on many levels, I noticed some drawback: The upper mid lift can be tiring, Especially If you pair this amp with the wrong earphones. I had issues listening to some song where the piano would be a tad too present. The snare of some techno recordings can be too much as well. With some recording that are a bit old and/or modest in terms of mastering the B1s will be unforgiving. The sound will be relatively thin, acid, and flaws would be overly apparent. "Angry" music will sound a bit too polished and relaxed.

Pairing in order of preference with their sound signature and how they react with the aune B1s:

• Puresounds PS-100-600 (U shaped, warm neutral) probably the best pair up. The sound is balanced and airy, bass is agile, treble is smooth. Overall sound is very rich and clear. Holographic sound stage. I could listen to any kind of music and be from extremely happy to satisfied.
• Seahf F650S (V shaped, neutral analytical) Sound is very balanced, very little coloration. It's objectively excellent although not as engaging as the PS, more kind of critical listening
• K's 300 samsara (Fun, warm lush) It's a sort of in between, it does sounds nice but not on everything, The warm lush characteristic sound of the samsara with the airy output of the B1s makes it not ideal. I think samsara prefer a thicker sounding source
• Blur (mid centric, neutral warm) Bad match, Bass doesn't extend beyond lower mid for some reason. Brass are thin and a bit gritty. Overall too clinical and mid centric.

Note: Using the Zishan Z2 DAP line out as a source, the sound is more dry, more 2D, somewhat hollow. Please bear in mind the price difference, considering it is ten times cheaper than the P1. It is nice to notice that the aune B1s is very transparent to it's source. And scale very well with a higher end DAC.

Aune B1s vs Revamp Acoustics Nuansa A1
Nuansa A1 is a discrete amplifier made by Revamp Acoustics, a one man business from Indonesia. It has similar spec in terms of power output, the price is significantly higher though (240usd+40usd shipping vs the 230usd with free shipping of B1s) They are both neutral amplifier although the approach is quite different. On the P1, The sound stage is smaller. There is less air between the instruments, the sound is more upfront and energetic. A tad less resolving, details are melted in the overall presentation. On high end recordings, the B1S is a step further in clarity and agility. The holographic feel is more present, each instruments feels more palpable on its own. However The sound presentation is more even and less colored on the A1. The A1 is more versatile for pairing with different earphones and/or listening to different type of recordings. The A1 has an analog quality. Old recordings, "lo-fi", still sound excellent on the A1.
A1 is smaller with its cigarette pack size, use a generic replaceable battery and is very sturdy. It does look quite rugged, especially next to the aune B1s which has a sophisticated allure.
It's hard to find a clear winner, it's all a matter of compromise on different factors.

#FINAL THOUGHTS
Aune B1s is a neutral amplifier with an airy sound, holographic presentation and excellent clarity. The value of this amp is probably unmatched at this point, It scales very well, has a very controlled sound, great build quality. Low gain is actually low and High gain is dangerously high.
From my experience, It pairs better with U/V shaped and neutral to warm earphones. My main issues are the fact that it can be too analytical with some pairing, the battery life is a bit short and there is no obvious way to replace it in case of degradation.

Aune B1s-$229 Class A headphone amp.




Specs/brief history (from their website):



AUNE B1S Class A Hi-Fi Audiophile Portable Headphone Amplifier (Upgrade Version)

Description

• The B1s is the 2nd generation of the B1, a portable amplifier which was well received across the world. With fully discrete transistors circuit design and output transistor with class-A biasing, the B1s is an extraordinary portable amplifier.

Origin

• In 2014, to break the saying that “portable class-A amplifiers are impossible”, we strove to create the B1, which marked the beginning of a new era of portable amplifiers.

Design

• The design of the B1s presents the beauty of balance, behind which is Aune’s 12 years of design philosophy.

Honor

• The B1 was the choice of over ten thousand audiophiles from around world. It received praise not only from users, but also media.

• In 2015 & 2016, the B1 was on the annual recommendation list of Soomal twice in a row, and in 2016 the B1 received the award of Best Creative Technology at Guangzhou HiFi Headphones & Digital Audio Expo by ERJI.NET.

The heritage of the classic

• The B1s is the latest generation of the worldwide well received B1. It’s born to be extraordinary.

High-quality yet affordable

• Natural and musical tuning, vivid reproduction, now affordable to all of you

Unique class-A output, mellow sounding

• In addition to the high resolution, great dynamics and ultra low distortion, the B1s uses class-A amplification, giving the sound a bit of warmth and tenderness.

Powerful and portable

• The B1s aims to extract every bit of potential from headphones with the rarely seen internal design of high voltage ±9V. While designing the amplifier circuits and tuning, we tested various headphones including those with high impedance and low sensitivity. The switches on the left side enable you to adjust the gain and current to fit different loads. The abundant power and excellent control make driving big cans like HD650 possible.

The perfect partner your DAP has been waiting for

• DAPs have developed very fast over the years. It’s time for headphone amplifier technical specifications to better match those of today’s DAPs. The B1s, with class-leading distortion lower than 0.0002%, is the headphone amplifier your DAP has been waiting for. In fact, few DAPs have distortion that low.

Great compatibility

• We used a wide variety of headphones and IEMs for tuning and optimized the entire circuit design, so the B1s has better control for headphones with low impedance and delicateness of high & mid impedance. Its compatibility with headphones had been significantly enhanced.

Duration

• Power supply is extremely important to an amplifier. The bipolar ultra-low-ripple regulator, together with the high-efficiency power supply design that enables the duration to exceed 10 hours (with current output set to 20mA), supports the B1s with constant purified power.

Specification

• Typical line output indicators
• Frequency response (from 10 Hz to 20 kHz): ±0.02dB
• THD + n: 0.00015% @300Ω
• SNR: 124dB @300Ω
• Crosstalk: <110dB @300Ω
• Max output: 6.443Vrms 18.4dBu(10Hz to 20kHz)
• Headphone output power: @300Ω 84mW , @600Ω 42mW ,@32Ω 74mW
• Class-A: 25mW/16R 50mW/32R
• Size: 125×65×18（mm）
• Weight:230g

Package

• AUNE B1S
• 3.5-3.5mm cable
• USB cable

Gear used/compared to:

thebit Opus #1S
Shanling M3s

Magaosi K5 (with Norne Vorpal SE cable)
Unique Melody Maestro V2 (Effect Audio Ares ii cable)
Campfire Audio Jupiter (Norne Vorpal Bal cable)
Vibro Labs Aria
Lypertek Mevi (Stock!)

iBasso PB3




Initiale:

Upon hearing that I would participate in the Aune B1s tour, I fondly remembered the Aune S6 of which I reviewed about a year ago. That came on the heels of the excellent ampsandsounds Kenzie, so the S6 had big shoes to follow. I had stated that, “To be able to be satisfied with the gear we choose, we must understand completely why we do. We must become that Illinois Bundleflower, from both the inside AND the outside. We must allow part of us to travel through those root hairs, with the bacteria as our guide and ride, then up the Xylem tubes, to all parts of the plant.” A reference I made to a prairie plant in which an acquaintance was using to help alleviate the loss of biodiversity in the prairie, and loss of biological diversity itself. Becoming one with the plant was the side focus, and becoming one with the gear we choose, and review was the point. I thought of that as I unboxed the B1s…thought of that wonderful week listening to the S6, and of how far I have come with my gear (far…!), and reviews (not far enough…).

I had mentioned to @Mshney how cool the B1s looked with the silver opening to the innards, lit by dual green lights on one side, and the red pleather on the other. Quite classy, and able to show off the wares, better than the all black. I rarely go for other than all black, so this was a departure from the norm, and a good one.

I was anxious to use the critter having spent the better part of the last month breaking in my new iBasso PB3. The PB3 was purchased almost solely on the aspect of using it as a dedicated balanced out amp for my DAP’s. Almost… After burning in the iBasso as per manufacturers recommendations, I listened. I liked. I liked a lot. The sound was almost 3D-like and definitely powered my DAP’s to a higher volume. I will have to save more on that for the dedicated review of the iBasso, suffice to say that I was satisfied with the purchase and the sound.

After the initial listen of the B1s, I was almost regretting that purchase…almost. If the Aune had a balanced headphone jack, this would be pretty much ideal. I understand why it doesn’t but think that Aune missed an opportunity here to add a worthy function. But that is OK, because many would not use this in that capacity. Paired easily with a Smartphone, this is a stellar example of how far the industry has come. To think that in a short time (you define it, I won’t), an amp, which cost $229 USD, could enhance ones Smartphone and you could be thoroughly satisfied would be a marvel. Of course, there are cheaper alternatives, which could do the same, but do they sound as good? Well, I’m not sure outside of a small sample, so I will leave you with that.

Coming in (to me) the typical simple straightforward Aune packaging, one is presented with the B1s, red pleather-side up, the charging cord and a longer 3.5mm bridge cable. I do think that this was on purpose, not only so one could configure the controls based upon whatever source unit you have, but also to vary which side you have showing…again choosing betwixt the two is tough…electronics, or that supple red pleather. I actually just like saying reeeeeeeed plllleeeaaatttthhherrrrr….OK enough of that.



Fin-n-Finish:



Impeccable. Top class. Seamless construction. No mismatched parts, toggles, jacks or inlays (the pleather). I hate to use the following, but it is an apt description, the construction belies the price point, and then some. While I am happy to state that this is becoming more the norm, I am also happy to note that this is of that build. Quite good and quite nice to see. Something I like is that one could place the pleather side against your DAP or Smartphone and have no need for that rubberized silicon piece of which most use to separate our “stacks.” That said, I am torn as to which side I like looking at more, the Pleather or the innards…it is a tough decision and one, which could gladly be debated by the owner. All toggle/switches work without fuss, and seamlessly. A click one way and you get high/low gain, class A/regular, or the on/off. The switches just work. I could also see removable glass panels on the one side, so you could switch op-amps, or play with the toggles, not unlike the iFi iTubes2. I also liken that look to staring through the glass at a Ferrari V12, or Lamborghini v12. I get that sense of horsepower.







Sound impresioni:

Well, this is harder for me to take. What with my hearing loss, I am confined away from the finer points unless I can absolutely pick them out. As also mentioned, my work with Passerines, afforded me that time to hone my listening skills enough to discern differences. And, I can add that there are some good ones, here.

What gives is a bit of a nicer richer more full sound than out of either the Shanling M3s or Opus #1S. Noticeably more so on the Opus. What to me is a somewhat thin (compared to the Opus #2 and M3s), clear, detailed sound is blown out of the water by the addition of the Aune. I immediately noted more detail, or rather clarity. That would be a better word. Clarity. Providing an almost holographic-balanced sound, I get now fully why Aune did not bother with a balanced set up on the B1s…it isn’t needed. That holographic sound perpetuated no matter the source, and no matter the IEM.

While this did occur, I did find the mids pushed too far forward for my tastes. I like having Carlos Santana’s guitar heard, but not so far forward, that it pushes all to the back. The great conglomeration of Santana is that all else is together in their psychedelic funk. This drug-induced mind-bending meld of musician and instrument is music to be felt. And that is good. It is lost a bit here, to that forward push. Moving to another Santana song, African Bamba, all is near-normal again. But there is that push still, this time with vocals. Is it something, which would prevent me from a purchase? Well, it is kind of a moot point, since I have the PB3, but if I had auditioned both side-by-side, it would have been a factor (read on for my conclusion of the pair).



Running the Opus #1s on Line-Out, I was presented with very little volume adjustment, even on Low gain. To me, this defined that the B1s is to be used in conjunction with your device, not subservient to said device. On all but my Jupiters that volume was all but unusable at even low gain/line out. With the Jupiter, I could get much more adjustment. I list this as due to the higher impedance and high sensitivity of the Jupiter, but I am no expert, here. I simply state my findings. Someday, I will get to the more technical side…someday…

Running the DAPs on normal Coax out, the volume was much more adjustable as one would expect. I was able to fine tune all this away, to my satisfaction. And the Aune simply sat back and allowed me that small bit of control. Listening to (Da Le) Yaleo, Santana’s excellent song, there is plenty of volume, and an ear-splitting volume could be achieved. And the sound is good. Quite good. Good separation, good soundstage, while that clarity is still there. I am getting somewhat mixed messages, but still think the mids too hot for my taste.



Soundstage/Separation/etc:

There is good soundstage width and height, but to me the depth seems to fall behind others a bit. Maybe I expected too much, but while I state the above, it is still quite good. One in which I could happily live with, due to the otherwise excellent characteristics. Proper to the aforementioned clarity, separation is good. Each instrument is where it should be, and as it should be.

I cannot find much to complain about with this fine little critter, except for battery life. I was disappointed to be honest, garnering only about 7 hours at most on A-class, and a bit more when A-class was turned off. Short of the standards listed. While not a big deal, since many of us carry portable power for our various devices, something in which to consider.



Comparison:

The only one of merit for me is the iBasso PB3, which as I stated I purchased specifically for the balanced-out headphone jack. To many, the loss of fully balanced in this iBasso lineup was a definite downside. That said, the cost became much more in line with amps of this spectrum, including this Aune B1s. Within $30 of each other, this is a wash. I will freely admit that I purchased the iBasso to replace my FiiO A5, too. While nice, the iBasso is a definite step up. I will lastly admit the purchase was to have a point of comparison with the iBasso and another amp coming soon. So, three points there.

My initial switch was one of wow, the Aune is quite good! While the iBasso is more powerful, the drive seems to be better with the Aune. More vibrant, better detail, and a bit warmer of sound. The PB3 also has a sound more midcentric, while sounding slightly more neutral. Depth of sound does seem to be better than the B1s, with width and height pretty much a wash to me. Both are of excellent build quality so there is no difference there.

Something I have not mentioned but indirectly regarding the Aune, is a slight reverb of sound. An old term we used to define a slight delay of sound, giving the music a sense of depth ala 3D, one could liken reverb to todays balanced, somewhat. This is where I think Aune didn’t have to go with the balanced out sound capability. The SE functions just fine, with the mentioned aspects.





Conclusion:

The Aune B1s has some pretty big shoes to follow with big brother S6. While not in the same category, it is clear than Aune put as much into the R&D of the B1s (family), as the S6 (one would hope, and of course they did). And, this shows. From the quality of construction, to the versatility of Class-A, the B1s is good, quite good. To make me rethink a recent purchase it has to be good. And it is. I write this listening to Santana on my Aria’s through the Opus #1s, and…the iBasso PB3. Why? To garner my final thoughts and take away the pain of sending the Aune on to @Wiljen. He will be very lucky, coming on the heels of another amp he has recently tested.

I would recommend a long listen of the Aune B1s, it is a really fine amp, and for those looking at amps of the slightly warmer genre and of single-end, this would be a very fine choice.

I want to thank @Aune for sending the tour unit along, and to @Msheney for setting up and managing the tour. It was worth the listen.

I have always thought that I could get something better from my portable setup without breaking the bank. In a search for an affordable Android DAP with two micro SD card slots, I end up with Pioneer XDP-100r. I love the versatility and its great sound, but I felt like something is missing. When I listen to my desktop setup, I can hear more detail, great nuance across the spectrum and more impactful but I would not mind that considering the price difference with my desktop setup and my DAP. The only thing that I am looking for with my portable rig is a fuller sound and I only get that only with Aune B1S so far.

Introduction

First and foremost, I want to thank Aune and @mshenay for organizing this tour and they did an amazing job in making sure that everyone gets their turn in a timely manner. The amp is sent to me in exchange for my honest review thus I have no affiliation with the company, but I will try my best to be as neutral as I could. Honestly, it is hard to not be biased when you love something but hopefully, I am not overhyping it too much

Disclaimer

Lately, I just started to be more serious on having a good portable setup but I don’t have any portable amp that I could compare with although I did extensively listen to iDSD Nano BL, iDSD Micro BL, and Chord Mojo; comparing with something that only exist in memory would not be fair for the sake of review. But, I’ll try to maximize every gear that I have in delivering a proper review on how the amp would sound and for whom it made.






What’s in the box?

Out from the box, you will get the amp itself, Aune B1s, a 3.5mm to 3.5mm short Aux cable and a USB cable for charging purposes. The accessories provided are nothing fancy in fact it would be amazing if Aune could throw in two or three rubber bands for stacking purpose. An inclusive case (or even sack) could be something that they can improve on the package bundle especially with the amp of this size, having something like a small bag is indeed convenient. The amp has a great build and it does feel solid in hand. However, the shape can be a little bulky for some, but it pairs nicely with my DAP. The back of the amp has a layer of leather for better grip and avoid any scratch or dent when stacking together with DAP. At one side, it has the gain, Class-A implementation and On/Off Switch slider and battery indicator on the other. At the bottom, you can it has the female micro USB port for charging and volume knob, line-in and 3.5mm headphone jack at the top. It has every feature that exists in the previous version of Aune B1 and the only difference is the addition of ‘s’ on the cover to indicate the differences. Of course, it has a slightly different circuit board implementation to lower down the output impedance to 1 ohm and has a better THD at 0.00015%. These little changes are what makes B1s a better version and a worthy upgrade from B1.






From Penon Audio

Description

· The B1s is the 2nd generation of the B1, a portable amplifier which was well received across the world. With fully discrete transistors circuit design and output transistor with class-A biasing, the B1s is an extraordinary portable amplifier.

Origin

· In 2014, to break the saying that “portable class-A amplifiers are impossible”, we strove to create the B1, which marked the beginning of a new era of portable amplifiers.

Design

· The design of the B1s presents the beauty of balance, behind which is Aune’s 12 years of design philosophy.

Honor

· The B1 was the choice of over ten thousand audiophiles from around world. It received praise not only from users, but also media.

· In 2015 & 2016, the B1 was on the annual recommendation list of Soomal twice in a row, and in 2016 the B1 received the award of Best Creative Technology at Guangzhou HiFi Headphones & Digital Audio Expo by ERJI.NET.

The heritage of the classic

· The B1s is the latest generation of the worldwide well received B1. It’s born to be extraordinary.

High-quality yet affordable

· Natural and musical tuning, vivid reproduction, now affordable to all of you

Unique class-A output, mellow sounding

· In addition to the high resolution, great dynamics and ultra low distortion, the B1s uses class-A amplification, giving the sound a bit of warmth and tenderness.

Powerful and portable

· The B1s aims to extract every bit of potential from headphones with the rarely seen internal design of high voltage ±9V. While designing the amplifier circuits and tuning, we tested various headphones including those with high impedance and low sensitivity. The switches on the left side enable you to adjust the gain and current to fit different loads. The abundant power and excellent control make driving big cans like HD650 possible.

The perfect partner your DAP has been waiting for

· DAPs have developed very fast over the years. It’s time for headphone amplifier technical specifications to better match those of today’s DAPs. The B1s, with class-leading distortion lower than 0.0002%, is the headphone amplifier your DAP has been waiting for. In fact, few DAPs have distortion that low.

Great compatibility

· We used a wide variety of headphones and IEMs for tuning and optimized the entire circuit design, so the B1s has better control for headphones with low impedance and delicateness of high & mid impedance. Its compatibility with headphones had been significantly enhanced.

Duration

· Power supply is extremely important to an amplifier. The bipolar ultra-low-ripple regulator, together with the high-efficiency power supply design that enables the duration to exceed 10 hours (with current output set to 20mA), supports the B1s with constant purified power.

Specification

· Typical line output indicators

· Frequency response (from 10 Hz to 20 kHz): ±0.02dB

· Output Impedance: 1 Ohm

· THD + n: 0.00015% @300Ω

· SNR: 124dB @300Ω

· Crosstalk: <110dB @300Ω

· Max output: 6.443Vrms 18.4dBu(10Hz to 20kHz)

· Headphone output power: @300Ω 84mW , @600Ω 42mW ,@32Ω 74mW

· Class-A: 25mW/16R 50mW/32R

· Size: 125×65×18（mm）

· Weight:230g


https://penonaudio.com/aune-b1s.html



Gear used for this review:
Headphones: Takstar Pro 82 modded, Sennheiser HD6XX modded and HD800SDR

IEMs: Westone 30, KZ ZS6 and ZSR

DAP: Pioneer XDP 100r

Amp: Aune B1S and Aune B1


Sound

Mellow sounding with tons of clarity. B1s is a kind of amp that let you immense with the music for hours without sacrificing any of those minute details. I am a fan of the modern song like EDM that sometimes needs an extra warmth for them to be more enjoyable. It doesn’t color the sound but stays transparent as Class A amplifier. Some might find that the amp is not warm enough, but not for me; it fits my taste perfectly. All of my dedicated solid-state amps are transparent and neutral but has a tube sound it. Not gooey, lush kind of warm but it gives a smoother top end without being rolled off. The highs are smooth with a great amount of detail enthrall the listener and shower them with enjoyment. The bass has a good body and articulate, but it does lack in sub-bass. I don’t have any dedicated headphone to focus on the sub-bass so take this with a grain of salt. Phenomenal vocal! Engaging vocal response with fantastic midrange is what keeps me coming back to this amp. The spacious sound makes every song sounded full and wide. The depth is above average, but the width is very noticeable especially with jazz, acoustic, classical and orchestra genre.



HD800SDR

Neutral sounding, spacious and smooth. I really love the spacious sound coming from the amp and with HD800, it did add more space, and everything seems so distant. I thought that this is the widest that I ever heard in a portable setup. Is that a good thing? Maybe but not for me because I felt like it’s not natural. The midrange lacks in body and lack in tonal density. Although, it does have a great tonal balance and I still enjoy them with a live concert and classical song but less so with modern songs. The bass could have more body and texture. HD800 is known for its clean and thumping bass but not like planar kind of bass. At times, the bass sounds a little thin and I am not basshead by all means but I do feel like the neutrality somehow sever the bass texture. When I play them with Fragile by Robert Lan (DSD), I noticed how smooth this combo is. The upper midrange is smooth and pleasing but did not sacrifice the details. Everything just sounds and flow well with the music. Oh My! I am loving what I heard. That’s for sure. I found that it does very well with DSD. I enjoy the whole show as if I am there in front of the band and not struggling to pick up every single detail in the songs.



HD6XX modded

Fuller sound, great imaging, spacious, musical and well-controlled bass. By far, this is the best synergy I have heard to date for my HD6XX for portable setup; they are so good to a point that I am buying the amp next month. The HD6XX/650 works great with my main setup and really enjoy them but with never like the headphone with a portable setup. With XDP-100r, I have tried Chord Mojo, iDSD Micro BL and iDSD Nano BL pair with HD6XX; while they are good, I am not really a fan of the synergy because I felt like something is missing. I have used line-out and USB connections with the amps and my DAP, but they never satisfied me; the case is different with B1S. I am utterly amazed at how full the sound was after a minute of listening to them. The ‘veil’ has been lifted and everything is just so detail. The great but smooth clarity, clear separations, spacious sound and well-extended treble. What can I say? I really fall in love with this. I tried them with the various genre from classical to rock and even metal (a genre that I never listen to in the past so take this with a grain of salt). The combo excels in every song that I listen to. The fuller sound and very engaging mids are what made me finds it hard to take the headphone off my head. Great tonal balance across the spectrum and the bass has more body and well-controlled. Again, I am surprised how good this combo is. If you already own Pioneer XDPX00 dap or Onkyo DP-1 and HD650/6XX, I would encourage you to try to listen to AUNE B1S. You’ll be amazed at how good they sound.



Takstar Pro 82 modded

Good tonal balance, engaging mids and spacious. Takstar Pro 82 is very transparent and really depends on your chain. After listening to the amp for at least 3 hours every day in a week, I can confidently tell that the amp has spacious sound, vivid and beautiful mids, great tonal balance, well-controlled bass and neutral overall. That is what it sounds like through Pro 82. It is more articulate, and I do find that it excels with most genre. I did not have the opportunity to listen to every genre but with most popular genre like pop, rock, alternative, punk, EDM, classical and jazz, it does quite well. However, the sounds can be a little thin and lack of sub bass. The treble is kind of rolled off with busy songs, but the bass still maintains clean with a better body. As I mentioned, the three things that really hooks me with this combo is how balanced it sounds, lively and engaging mids and its wide space albeit the lack of depth.

IEMs pair



Westone 30

Balanced, great detail, good separation, and wider soundstage. Westone 30 has the best depth compare to my other IEM albeit a quite small width. I thought it sounds similar to HD650 but lack of vivid vocal; with Aune B1S, the problem pretty much solved. I really enjoy vocals and mids with this combo. It brought the singer a few steps back that allows for more space to breathe. I used to enjoy modern genre more than classical with this IEM but enjoy them equally now; cleaner bass elevates the capability of W30 to sounds amazing with every song I listen to. The drum thumps at the right time and I can virtually point out where it came from in the song. I am a fan of W30 but I do think that it could do a little better in detail retrieval and the solution has appeared right before my eyes.



KZ ZS6

Articulate instrumental timbre, amazing detail retrieval, and clean sounding. I would expect the amp will sound amazing with KZ flagship’s lineup. The sound is surprisingly clean at any volume level with an output impedance of 1 Ohm. ZS6 can sound thin especially with classical and jazz songs but its wide soundstage and amazing separation compensate the weakness in those genres. Aune B1S adds thicker sound to most instruments plays through the ZS6 and it sounds uniquely articulate. I am genuinely amazed by the realism that it brings to the music. More energy coming from drums and guitars but never overwhelm of being harsh or fatigue. I noticed that zs6 biggest issue, the treble spike, is solved. The highs are much softer and articulate; I do enjoy more songs with the ZS6 now than how I was before. I found that male vocal is more dominant in this combo. Female vocal could be softer because the combo makes female singer to sound strong and masculine. Bass still lacking in quantity but has a better body and goes slightly low. With Aune B1 (2015 edition), the bass is punchier, but I still prefer B1s because it excels in every other part.




KZ ZSR

Smooth, airy, great clarity, spacious, musical and clean sounding. ZSR is a smoother version of ZS6 especially in the top end but also not as detail. B1s brings an awesome musicality to ZSR and provides a very balanced sound across the spectrum. Smooth sounding and very articulate treble. Every KZ ZSX flagship owner kind of had an issue with them but not anymore. The music has more space and wider soundstage. Also, it allows you to breathe throughout the song and notably helps when you play a complex song that longed to be fatigue at long listening hours. They are airier like HD650 despite being isolated as an IEM. It goes deeper and wider that gives fuller sound to ZSR. It has been forever since the last time I enjoy Pink Floyd because they could sound thin without proper headphone/IEM, but now, I enjoy them so much with ZSR. Imaging improve greatly; if you’re listening to concert and orchestra, you will feel like you’re in the front row. Instruments separation are more noticeable and let you immense with the music. Just you and the music. The overall sound is balanced, thicker and more vivid. The bass has more texture and well-controlled. It is definitely a better combo than ZS6 and does I love them? Heck yeah, I do!



VS Aune B1 (1st Gen)

I am amazed by the B1s performance then I had this thought in mind, “how does this compare to the first gen?”. Thus, I decided to look for a used Aune B1 (2015 edition) and gauge how far does the B1s evolve. Unfortunately, I received my B1 the day after I ship the B1s to other people on the tour. How unlucky. But hey, I still remembered the sound. I think. After I received the amp and stack them up together with my DAP and ZSR, my first impression was… YUCK! This amp is worse than I thought. Well, I guess it’s not fair to judge it too early since the previous owner only uses it once. I let the amp burned it for about 100 hours and give them a second try. It sounded much better but still does not meet my expectation. The 2015 edition has output impedance 10 ohm which quite high and not the best condition for a super sensitive IEM. I also noticed the treble is harsher and more on the brighter side compares to the B1s. The vocal is less engaging but still clear and detail. The bass has more quantity and body but not as articulate. I noticed a distant hiss when I pair them with ZS6; not a big of a problem but could be an issue for some. Out of all my IEMs, I only enjoy the amp with Westone 30 because with every other IEMs especially KZs, I find it too bright to my taste and fatiguing. Honestly, I am not disappointed because it is quite good; transparent, great clarity, more bass quantity and good imaging with above average separation. But, as I spoiled my ears with B1s first, I can’t move on with how good it was. Thus, I decided to sell the B1 and get myself a B1s and as I am typing this, the B1s is already on its way. At this point, I can rest assured knowing that I am good with portable setup and not needing any other gears.

Conclusion

I tried to be very honest in any of my review, but I am confident to say a lot of wonderful things about something when I love them myself. As always, take this review with a grain of salt but if you’re looking for a mellow sounding amp that has tons of detail and clarity, look no further because Aune B1s got you covered. I heard what I heard. Period.

It's that time folks! I've got a new offering from Aune in the form of a powerful portable amplifier resting in my hands. Before I start with the juicy details I'll start with a little info about myself.

I listen to a wide variety of music however my test tracks vary from EDM, classic rock, classical, alternative and everything in between.. alright alright.. no country I'm an over ear kind of guy as IEMs don't get me where I need to go when it comes to musical enjoyment. On a side note, I'm not being compensated in any way for this review. My thoughts are just that. Also I've come to appreciate the sound each piece of equipment has to offer and realize the importance of synergy. Some chains just simply don't sound right.. finding the magic isn't always easy my friends.



Enough of that.. I'm sure you want to hear about the B1S already right?! Well, I was a bit hesitant when I read up on the original B1's main complaint of not having enough driving power. I can honestly say however this can drive the toughest of my cans into a flaming pile if I got dial happy with gain and the class A switch enabled. The only can I would say wasn't driven 'well' was my HE-560 which seems to really, really like gobs of power to get where it needs to go. It got loud, just not full. How many people are going to be specifically pairing that kind of headphone with the B1S? Yeah, none.. but it is good to know Excellent pairings were with all of my dynamic headphones and even the LCD2C did quite well.




Some like to say every solid state amp sounds the same.. well - I have to disagree. Every amp I've heard has a variation.. its own sound signature. It doesn't swing as wildly as some say but it is definitely there. The B1S's signature I would say is a very friendly tuning. I can listen to the nastiest of my demo tracks (they are there specifically for a good reason) with ease on this amp. There is some deep sub bass roll which honestly I appreciate. Some very low frequencies can cause a bit of discomfort in some of my amps in the tune of fatigue.. not so with the B1S. This can also be said about the extreme highs, which have sparkle but don't seer my ear hairs right off.

The B1S CAN be a bit of a midcentric amp depending on the setup, however this also gives it the ability to pair so extremely well with many types of different headphones and sources. I can't stress enough, this is a subtle thing, and something that makes this amplifier able to please more of an audience. For something portable and easy to tote you definitely want a tuning like this. Aside from that the B1S is a surprisingly neutral amplifier. Very clean, very powerful and quite worthy of mating with any DAP.

The bass hits with authority and is visceral through the frequency range with smooth transition despite a low amount of roll at the bottom. The mids are heaven for vocal music and retain great warmth. The highs are extended yet controlled at end of the spectrum as to not pierce, even if the source material does. The tuning has only one downside, it is easily appreciated but not immediately engaging. It all comes down to your tastes however and I must say this amplifier is worth trying out to see if its your cup of tea.

Dimensional aspects of the amplifier are decent, although a little bit bulkier than my X5iii.



Sure does look absolutely beautiful though. It does come in a black color as well so.. definitely one of the most eye appealing amps I've ever seen, with good sound quality to boot. There are a couple of downsides to be aware of. It did get a bit warm in Class A mode after extended use and when enabled the battery life wasn't the greatest. A bit of a SQ hit when disabling this feature but nothing to write home about.. honestly, I'm not all sold on this feature as it is just another circuit being introduced into the mix.

When compared to my Fiio A5 the sound was cleaner.. more neutral however less engaging as the Fiio reached deeper. The A5 is more colored in the way it alters the sound though. It all comes down to flavor and what cup of tea you prefer. When using my iDSD BL as a source I did prefer the BL's integrated amp - however I'd say this comes down to synergy. Take comparisons with a grain of salt, my ears are very different than yours I can honestly say though that this amp is definitely worth the asking price. Some pieces of review kit don't get listened to every day for the duration... this one did It'll be missed. - Thanks for the read my fellow fi'ers!





Sources: BifrostMB Gen5, iFi iDSD BL, Fiio X5iii, Galaxy S Voodoo Ed.
Amps: iFi iDSD BL, Jotunheim, Fiio A5
Headphones: Sennheiser HD6XX(Modded), Hifiman HE560 and HE400i, AKG K702(Modded), Audeze LCD2C, Beyer DT770(Modded)

To B or not to B, is the question... corny jokes aside, most portable amp manufacturers don't mention what class their amp operates in. Simply because each of the different modes have their own benefits and drawbacks. How ever, the exception to this rule is with Class A!

What sets a Class A amp apart is it's always on or always ready operating mode. Which lends itself to a faster response times in theory because the components are always ready. Now you may be wondering, if Class A is indeed the best why doesn't every one use it for everything? Well two things, it's very inefficient, being always on means a lower battery life is expected and there will be heat, how ever when implemented correctly as executed by Aune I found neither of these "draw backs" to be troublesome!

Priced at $229 the Aune B1S certainly proves it self an amazing value! In stock as of this writing from both Amazon and Penon Audio.



Build Quality
Aune's B1S is beautifully constructed, with a brushed metal chassis encasing a beautiful clear panel with either a red or black textured back. I found no visible gaps in the chassis, nor any chips, cracks or even scratches. The entire design is seamless, beautiful and inspires confidence!



The 3.5mm and micro usb jacks are solid, with no play,wiggle or action on them! Firm, solid connections every time.





The volume knob is smooth and precise, I had no problems with volume jumps or channel imbalances. Additionally the side sliders have a good solid action.

Function
The B1S offers both a voltage gain slider and a current slider, allowing it to operate in both 20mA and 40 mA current modes. For the purposes of my review I keep current at the 40mA output and adjusted the gain as necessary.

Functionally, the B1S had plenty of space on it's front side for everything. There was no crowding even with thicker 3.5mm inter-connectors, I was easily able to adjust the volume even with the largest of my 3.5mm cables. Plus that fact that everything was front mounted made it pocket friendly. It drove everything from my HD 800 to my Hifiman HE 4XX with ease and authority, but it will not however drive larger or less efficient planars such as the Audeze LCD 2 my HE 4 or less efficient dynamics like my AKG K240 or my ZMF Eikon. Aune did not create this product to be a power house, but rather carefully crafted it to deliver a phenomenal quality of sound for use with more efficient headphones and iems.

Sound
Just how phenomenal is the question no doubt. Typically I associate a sort of thickness or warmth with Class A amplifiers. The B1S how ever did not meet my exceptions, rather I found it to have much more clarity and edge than I was expecting! If fact what little warmth it brought was almost always non invasive.

The B1S characterizes it self with a natural presentation steeped in an inky blackness paired with impressive resolve. Transient information really stood out while using this amp, though there was a slight lack of macro dynamics or aggression. Micro dynamics or small changes in volume were vary apparent, how ever larger more sudden shifts lacked a little. Frankly though with so many headphones and DACs offering a more aggressive sound I found this minor drawback to be mostly harmless.



To help gain some insight on how the amp performed I pair'd or compared it with each device pictured and used my Modified ATH ES-10 as a reference point. I also took the time to compare how the single ended performance of the B1S compared to the balanced output of my Shanling M3S and Geek Out v2+



Shanling M2S Line Out into B1S vs M3S SE and Balanced Out

Overall I found the M2S to be a poor partner for the Aune B1S, as both have a more natural sound. The music as a whole lacked excitement. The M2S and B1S are voiced similarly and as such didn't really impress me. How ever you guys may likely remember that the Line Out of the M2S didn't really scale all that well, all in all I think single headphones owners of the M2S would be better off upgrading to the M3S and utilizing it's balanced out put.

Specifically speaking, the M2S and B1S combo had a wider image over the single output of the 3.5mm Single End output of the M3S. While the M3S offered a better sense of both height and depth, resolve and transients response was similar between the two. The single ended M3S had a slightly more energetic envelope, with a slight de-emphasis on the decay and release of notes. On the other hand, the M2S and B1S had a touch of emphasis on the decay and release of notes.

When using the balanced output of the M3S, the B1S and Shanling M2S only had their uniquely magical romantic mid-range as an advantage. An while I LOVE the M2S, I do feel it brings the most value when it's alone.

Now, I would imagine the Cayin N3 would make a good partner for the Aune B1S. It had a distinctly exciting almost dry sound and it's line out scaled better.


Shanling M3S Line Out to Aune B1S vs Geek Out V2+

Wow, this combo tough to part ways with. Priced at about $500 for both THIS combo is in my opinion the golden middle ground in portables. And what's best about it is that it's NOT balanced! Going balanced can cost anywhere from $60-120 per cable per headphone. The price varies depending on what headphone that you have, so for those of you who own a single primary headphone that you use both at home and while traveling will likely find going the balanced route worthwhile. How ever, if you have more than one primary headphone then the balanced option because less cost effective and can be almost cumbersome.

That said, let's break down how it compared again'st both the SE and Balanced output of the Geek Out v2+ as well as how the M3S own Balanced Output compares to the Line Out combo with the Aune B1S.

Lows;
M3S Balanced vs M3S LO Aune B1S; Comparatively the M3S balanced output was consistently drier and sometimes tighter. This was most noticeable with synth bass lines, with EDM and some Hip-Hop I found a little bit of emphasis and smearing in the low end with the B1S. Though for most bigger stringed instruments and drums especially the B1S had the advantage. It's slight touch of decay made for a more natural envelope overall in comparison to the artificially faster M3S.

M3S LO Aune B1S vs Geek Out SE/Balanced; Sadly, for the Geek Out v2+ it's SE output sat in the middle of this pack. It did nothing wrong but it wasn't as clear as it's balanced output and wasn't as engaging as the Aune B1S.

For the most part balanced out of the Geek Out v2+ proved to be the more technically correct presentation, with a better sense of power and overall resolve. On the flip side the Aune B1S again had a more natural envelope. This most obvious with natural skinned drums, the Geek Out V2+ was sometimes too percussive lacking some of the body or resonance of the instrument itself, just a lot of attack with too little decay. With the Aune B1S there was enough attack and never too much decay, an every single time it's envelope was just more natural. Though, the Geek Out V2+ did better with some headphones than it did others.

Mids;
M3S Balanced/Geek Out V2+ [SE &amp; Balanced] vs M3S LO Aune B1S; Tactility and edge stand out the most with the M3S/GeekOut v2+, never too hard though always distinct. How ever, there was just something magical about the B1S, with a well balanced headphone in every instance.

In the event that you happen to have an already soft romantic headphone and you'd like a bit more edge and aggression, than the Geek Out v2+ or M3S Balanced out will suite your needs best. However, if you don't mind a gentle'r more polite tactility, you'll find that even warm headphones like the HE 4XX pair nice with the Aune B1S!

Specifically, with the HE 4XX I found horns and vocals to have an added creaminess to them. Never lacking any airiness or breathy notes. Even heavily distorted metal guitar riffs had plenty of bite and were beautifully offset by gorgeous creamy solos! Though, while never overly saturated, the Aune B1S was still has a rather wet mid-range presentation.

Highs;
M3S Balanced vs M3S LO Aune B1S; Native balanced out from the M3S proved to be a little too sparkly some times, while this helped draw attention to ambient noise present in the track it also detracted a little from some mid-range textures. Though the balanced output of the M3S had a nice sense of excitement!

The Aune B1S wasn't as hard but was at times a bit under-defined. In some cases I found snare drums and other snappy percussive instruments to be a bit taken back compared to the M3S. Though there was a nice added sweetness to metal bells.

M3S LO Aune B1S vs Geek Out v2+; The Geek Out V2+ has an amazing sense of excitement and presence up top with no lack of detail or resolve. In most cases, it's drier presentation helped define vibrato more readily in bells and more clearly defined string/fret noise in guitars and other hand operated instruments. Unique though to the Geek Out V2+ as well was it's sense of space, while having it's own top end emphasis it did not take away from the mid range any.

The B1S presented it self more smoothly in every instance and often lacked resolve and clarity when compared to the Geek Out V2+.

Imaging;
M3S Balanced Out vs M3S Line Out Aune B1S; Imaging and precision were very impressive on the Aune B1S. In comparison, the M3S while equally wide, was often not as deep nor as precise. It's often more emphasized top end sometimes detracted away from the sense of spaciousness.

M3S Line Out Aune B1S vs Geek Out V2+; Once again the B1S impresses, for the most part the two were on par. In some cases with a more intimate master, the Geek Out V2+ balanced was airier, but otherwise both were excellent.

Resolve;
M3S Balanced Out vs M3S Line Out Aune B1S; The M3S had more resolve on both ends of the spectrum but was overall just behind the Aune B1S in the mid-range resolve. It's top end emphasis brings out more ambient noise, breathing, spoken words in the back ground, foot steps, the occasional air conditioner compressor starting up and things like these. How ever this added attention to ambient noise does sometimes take away from detail in the mid range.

The Aune B1S on the other hand often missed out on some of this ambient noise in exchange for providing a clearer picture in the mid range. The slight variation in tone of strings as they come to a rest, a change in a singers voice just after they take a breath a little bend at the end of a Guitarists solo. Details like these were more apparent with the B1S. Not to say the M3s native balanced out lacked any of this, but these details were not as vivid from the M3S as on the Aune B1S

M3S Line Out Aune B1S vs Geek Out V2+; The Aune B1S for the most part did not match up to the Geek Out v2+ sense of resolve especially with darker headphones, the only time it did was with brighter detail oriented headphones such as the HD 800.

Overall;
What I found was overall, the Aune B1S paired with the Line out of the M3S did the most right with the widest range of equipment. While the M3S was very impressive it only really shined with darker or more relaxed headphones and requires use of the balanced output. An the Geek Out V2+ can be very polarizing, with some headphones I love it, with others I absolutely hate it. Again, the combined line out of the Shanling M3S,and Aune B1S check all of my boxes and provide what was the most enjoyable presentation and timbre overall. It was by no means the most technical listen, but rather put emphasis on the details that I enjoy the most while keeping a perfectly natural timbre. An better yet it allowed me to finally enjoy my HD 800 on the go!

In keeping things balanced, as impressed I was with the Geek Out V2+'s balanced performance, it's lavish praise ends when the Aune B1s is sourced with an even more resolving Digital Audio Player.

With what I felt was a top of the line source, the B1s personality shown the brightest. It brings a touch of warmth and smoothness to what ever you pair it with. In the mid-range DAP market you'll find clearer, brighter more energetic ESS Sabre implementations will pair wonderfully with it. How ever with the HM 901 which is itself quite linear, in that it has neither emphasis nor de-emphasis, the Aune B1S was hit or miss. While this system was consistently better than the Geek Out V2+, it was equally as polarizing.

With the 901 as source, the B1S maintained every bit of clarity and precision the 901 offers, I did use the hm 901's HD filter however as opposed to the Vintage filter that I personally prefer it with. The problem however, arouse with the timbre. At times there was too much sweetness in the mid range and a lack of resolve in the lows and clarity up top. Not to say that the Aune B1S is a warm amp, but it does add a bit of decay, and body into the mid range. That said, it will work best with brighter headphones if your planning to pair it with a top of the line Digital Audio player.



The most relevant comparison if of course to my Head-Amp Pico Power. With the HM 901 I prefer the vintage filter as this helps to de-emphasis the top end glare that's inherit to some ESS Sabre Dacs by using a high pass slow roll-off filter. The Pico Power reflects this nicely, adding virtually nothing to the tonal presentation and only improving the existing clarity and resolve. The Aune B1S on the other hand sounded best with the HD filter which maintains a linear top end response from the DAC.

I will also mention that I can NOT stand my HD 800 with this system... regardless of the filter or the amp. As I just find it to be too boring... very non engaging.

Still let's break down how the two amps compared with my modded Audio Technica ES 10.

Lows;
HM 901 Line Out Aune B1S vs HeadAmp Pico Power; Wood winded stringed instruments were often a bit too thick with the Aune B1S, while there was a nice amount of fret noise there was often too much decay.

Bass guitars and larger drums found a slight lack of power as well with the Aune B1S. There was a marginally diffuse nature to their presentation, with the Pico Power presenting a more defined leading edge or attack.

Switching to the HeadAmp Pico Power resulted in a nuanced more clearly resolved and articulate presentation. The envelope with the Pico Power was cleaner, a more defined decay that transitions into a very clear release. The vibrato or slight variation in tone of some of the larger stringed instruments was a bit smeared with the B1S. Again, swapping to the Pico Power I was able to more clearly follow the slight changes in pitch as the notes slowly faded beneath our threshold of hearing.

Mids;
HM 901 Line Out Aune B1S vs HeadAmp Pico Power; Each of these amps had it's own strengths and weakness in relation to the mid range. With busier sections of music the HeadAmp Pico Power maintains it's clarity and purity. With Classical duets, such as those featuring only two instruments, it can at times demonstrate some dryness. Though this is likely a result of the HM901 and less of the amp it self.

How ever, the Aune B1s having just a touch of sweetness does better with these classical Duets. Though with busier sections of music it does not retain as much of the HM901's clarity and can smear the sound ever so slightly.

Highs;
HM 901 Line Out Aune B1S vs HeadAmp Pico Power; Again the HeadAmp Pico Power takes the cake, keeping more true to the source and presenting more resolve. If though you want to add a little sweetness up top than the B1S is the way to go!

Imaging;
HM 901 Line Out Aune B1S vs HeadAmp Pico Power; This one was tough, in most cases the HeadAmp Pico Power proved to be a bit deeper and more spacious, how ever the Aune B1S was consistently a bit wider. Not that it lacked space but it wasn't always as airy, though the added width does create the perception of airiness especially with headphones that are themselves very spacious. Though with more intimate headphones, the slight decrease in air and spaciousness is noticeable.

Resolve;
HM 901 Line Out Aune B1S vs HeadAmp Pico Power; Again, the HeadAmp Pico Power proved to be more resolving, having no emphasis nor any de-emphasis. While the Aune B1S wasn't far behind, it did in some cases simplify some transients as a result of it's slightly emphasized decay.

Overall;
All in all I think the Aune B1S plays best in the market it's priced around. While it does scale nicely, when compared to what I feel is product designed especially for a top of the line portable digital audio player, it doesn't prove as competitive. How ever, tonally speaking if your looking for something that adds a bit of sweetness than the B1S is perfect for you!

Of the various portable systems I own, to date none of them has been good enough for my HD 800. Most are either too technical and just joyless to listen to, or a lot of fun but technically lacking. The idea of owning a flag ship headphone is to have the very best! Thus when I'm listening I have no desire to lug around this massive headphone to listen to a either a fun system or a technical one. Even my own HeadAmp Pico Power proves to often be a poor amp for the HD 800... as it's inherit flaws are by no means masked by the almost invisible Pico Power, making for a very technical but mostly lifeless listen.

That said, the Aune B1S and Shanling M3S proved to be the FIRST portable system that combined both pleasure and technicality into the HD 800. An while most of you will not by stepping outside with your HD 800s, some of you may want to enjoy them away from your desk/office/bedroom or where ever you have your main system!

That said, while the pairing was not the most resolving, not the most spacious, didn't have the tightest bass, nor the most extended top end. It was with my HD 800 simply pleasurable to listen to! With the Aune B1S and M3S I truly had the best of both worlds!

The B1S added just a touch of meat to the low end that the HD 800 needed, additionally it presented a phenomenal sense of resolve pair'd with a pure creamy mid range. An the top end had exceptionally clarity with just a touch of sweetness. So thus those of you who own headphones with a neutral tuning will find that for portable use the Aune B1S is really top notch, especially with some of the very dry portable products it's priced around.

An when I pair'd the HM901 with the B1S I found the bass to be too intrusive, the HM 901 it self has a some what powerful sound signature. Thus when pair'd with an amp that is anything less than invisible, it often winds up having too much of something. In this case the combo just had too much emphasis in the lows for my tastes and enough enough texture and clarity. While this was nice on some tracks with the HD 800, it was not on others.



In conclusion and all things considered the B1S proves it self an incredibly pleasurable portable amplifier. Going back to the HD 800 Shanling M3S and Aune B1S combo, that was a $500 system that I found drove a $1000 headphone beautifully! An it did so better than portable systems that cost in some cases three times as much! An while there is always better, what the Aune B1S delivers is value and balance. In the land of diminishing returns the B1S is with out a doubt designed and priced in such a way that makes it by far one of the best bang for your buck purchases as it does so much right. Chasing after upgrades is often met more by differences than true end over end improvements and really requires an almost super specified system in the end.

For example, I have two portable amps in my collection. My HeadAmp Pico power and my iBasso PB2. My Pico Power is single ended and has a specially selected Li-Ion batteries to help it sustain more current for power hungry but efficient Planar Magnetic Headphones and easier to drive dynamics. My iBasso PB2 on the other hand has an entirely separate battery pack, upgraded Op Amps and current buffers, it specifically drives balanced headphones that require a lot of power. Such as my Hifiman HE 4 or my AKG K240. Each of these amps ran me around $500 after all upgrades and modifications, and both were the result of quite a bit of trial an error. The iBasso PB2 is also now discontinued... so while better does exist, it doesn't come easy in portable systems.

Hence, going back to the Aune B1S it's got an amazingly black back ground, a wide sound stage and unique magical mid range! It's euphoric sweetness is unmistakable and really adds something special to any system that finds it self uninviting! It's uniquely sweet tonal balance gives with plenty of resolve and enough flexibility to help patch up imperfections in both your source or headphones, while also bringing out the best both! An what more can you ask from an amp, that to simply add enjoyment and pleasure into your listening experience!