Ah... The elusive Shure SHA900 portable amplifier. Shure as a company needs no introduction, yet this product, while priced like the SE846 earphones, gets only a tiny fraction of its attention.
Well, I think it's time this gets a review on Head-Fi, and shed some light on the great, the good and on what's lacking.



My background and equipment used:
I've been with Shure earphones for about a decade now, starting with the SE210s. Along the way I tried all sort of headphones, earphones, amplifiers and DACs from other brands, and while each had its unique impact, for my personal preference there was no beating an SE535 plugged to a silent amplifier.
The SHA900 has been purchased about a week into owning a pair of SE846s, a small risk I took to accommodate the earphones (as there's a very small amount of reviews out there). To that point, my main setup and comparison point is a Schiit Vali 2 and Modi Multibit stack.
The impressions are made on a month-old SHA900 unit with 100+ play hours (on DAC mode) and EQ set to bypass/off.


Sound impressions:
There's two things I don't expect from high-end audio equipment: The first one is to make my "crappy" mid-fi headphones (Philips SHP9500 for instance*) sound anything worth talking about. The second, is any comments on the sound from my audio-Average Joe friends. So when I took the SHA900 to work, gave a listen to a colleague who's proud of his $100 Beats-knockoff, then a friend who has proclaimed he cannot hear a difference between his Skullcandy and my HE-400i, and both go "hey, this sounds a lot better!", I know this time I have something different in my hands.
The first thing that hits you with the SHA900 is the soundstage. It has a spacious, open sound, which makes focusing on instruments an easy task. Once you get acquainted with that, the second thing that hits you is the detail each individual in the music has. Listening to one element can be as enjoyable as hearing them all together. The third and final initial impression point is the decay of instruments, in particular the bass. Admittedly, the majority of the evaluation was done on a pair of Shure SE846s, which handle bass exceptionally well, but string instruments can also feel that they just fade on and on to absolute silence.
Speaking of, it should come as no surprise that this amp is silent, seeing as Shure advertises it to synergize very well with its in-ears. True enough, the SHA900 is easily the most silent amplifier I've ever heard (Fiio E12A included). Interestingly (and pleasantly surprising), this silent character applies both to background noise (hiss), as well as to the music itself, which feels to me as if there's more silence between instruments and during transitions. The cause for that is likely composed from various properties of the sound (width, I guess), and I find it as one of the strong points of this amp.


Macro is what I feel this unit excels in with flying remarks. I can drag on all day about punchy bass, full round vocals and airy guitar strings (all which are true), but it's the experience of listening to a full album, start to finish, which gives the final rating, and the SHA900 is capable of offering an unforgettable ride. I define a good audio experience as watching a good fantasy movie. Half-way through the film, you find yourself immersed in a different world with a different state of mind. In music, call it either ambience, musicality or just detail, for me, it is the sensation of being engulfed in the music, as if surrounded by or inside it. It may as well have started with the Shure SE535, having that numbing effect. The SE846 then further improved that sense of immersion, and the SHA900 has truly complemented and perfected it. Fed by a Schiit Modi Multibit, for the first in a very long time, I stopped caring to what I was listening through and simply enjoyed what I was hearing. This amplifier is the first piece of equipment I feel inclined to push the volume higher the more I listen to it, having the hearing loss warning etched into the unit being a testament to that.

(*) They sound great for their price, actually. Just passing a point. ^^

With the Sennheiser HD 650 (01/12/2017 update):
I felt compelled to update the review with a recently acquired Massdrop Sennheiser HD 6XX (which are basically the 650s), for two reasons:

1. They are said to be very revealing of the source (which turned out to be true).
2. Although less musical and not as refined, they sound remarkably similar to the Shure SE846.

The impressions are on about a 150 hours of burned-in unit.

In an even greater effect than the Shure in-ears, the 650s soundstage through the SHA900 simply pops. I literally got a comical "eh?" moment after re-plugging the headphones from the Vali to the SHA900 during ProtoShredaniod's Orbital Shred Station (yeah, a bit underground I guess, but you'll get the same result with Nightwish). Separation, as a result, is superb as well.
Frequency extension and decay sound accurate and whole, so in regard to speculations on the amp not having enough power (the "95mW into 42 Ω" spec), I feel the unit has no problem properly driving the 650s, with volume not being an issue.
One noteworthy sound characteristic of this pairup is the "silent sound" I've mentioned (perception of silence between instruments), which can be either a positive or negative thing, based on preference: While the outcome is a wider, more detailed presentation, it can occasionally sound analytical and somewhat dry. I feel this is most evident in brickwalled records, but overall really dependent on the album and seems to be irrelevant to genre.



The DAC:
I've seen the unit's DAC being referred to from "old" to "crap", without any further explanation, so I wanted to dedicate a section of the review to address the subject. The internals of the SHA900 are largely a mystery. With a rather odd spec sheet, the amp section is possibly a unique Shure design (stemming from the KSA1500). The DAC however, is the Cirrus Logic CS4272, which came about in 2005 (hence the 'old' moniker).
Now, my experience with pricey DACs is rather limited (see comparisons section), so between the Schiit Modi Multibit and the original Fiio X5's TI PCM1792A DAC, the SHA900's DAC veers substantially more towards the prior. While obviously a function of implementation, the TI DAC sounds muddy and muffled in comparison to the CS4272. The Modi however does sound more detailed, spacious and more realistic - not as far as calling it night and day, but it's noticeable.
Either way, as part of a portable package, while not on the same level as the amp, I would still rate the DAC as very good and a well worthy match. It does not negatively affect the feeling of immersion I mentioned earlier, and while I do enjoy the SHA900 more when fed by the Modi, I don't get disappointed when I listen through the DAC on the go.
I am aware that there are very good portable, even multibit DACs out there (Chord Mojo the first that jumps to mind), but I've read reviews that go both ways, and as I haven't heard it myself, I can't comment on it. As for delta-sigma, I am curious about the recent AK4490s popping all over the place, and will update the review if I get my hands on a decent one.

Opposed to a mid-range AK4490 (15/04/2019):
I did finally get my hands on an AK4490 in the form of a Schiit Fulla 2. I'm no longer into the hobby (enough money spent, plus Tinnitus) and it's not really apples to apples comparison, so I just did a swift 45 minutes of direct A/B testing using the Fulla's line-out.
I actually expected the AK4490 to introduce something new, or make sounds the CS4272 couldn't do, but it turned out the ol' SHA900's DAC outperforms it in both micro and macro: Dives deeper on both edges of the spectrum, has more realism and a wider soundstage, and frankly, the difference gets more pronounced the more I listen to it (the AK4490's cotton ball gets bigger). I feel the performance difference is narrower than against the Modi, so that's more or less the DAC's spot. I still stand behind what I said two years ago about the DAC being quite good, but I'll definitely understand having my opinion challenged.


Usability and user interface:
Operating the SHA900 is simple enough, with four buttons, three plugs and one small good-looking OLED screen. On the side, there is a slide-click lock button with the power button just above it, which also functions as the 'back/cancel' command in menus. It takes about half a second of pressing to fire the amp up (something a lot of companies could learn from), and the usual 3 seconds to turn it off. At the bottom there's the input switch, which sets the unit into either DAC or line-in mode. Needless to say, the unit can be charged while using either, and I don't notice any audio artifacts when charging and listening to music simultaneously. Finally, on top, there's the volume control knob that can be double-clicked to enter the menu, and single-clicked to navigate it.


On actually using the amp, I'm unfortunately greeted once more with the disease that plagues the complete majority of amps on the planet, which is the volume being too god damned loud. The amp has 25 volume levels, and even with Shure's in-ears (counter-intuitively), when plugged as a DAC, level 2 is enough to sound what I consider loud. In line-in mode, with input gain set to -20dB, 4 is still my personal limit. While a point can be made that there are many inefficient headphones out there (personal limit for the Hifiman HE-400i is level 5 on high gain), my expectations were for a much more fine-grained volume control. On the bright side, channels are absolutely balanced from the lowest volume point, and, as I mentioned, in line-in mode the input gain can be attenuated by -10dB and -20dB, which is a must when fed from a desktop DAC. Curiously, the spec sheet states for an adjustable gain range of -60 to +17 dB, which isn't accessible through the UI.
Speaking of which, the SHA900 sports the most simple and practical UI I came across in a portable. Double-click the wheel and you're greeted with an 'Equalizer', 'Audio' and 'Utilities' menu entries. The EQ admittedly, is my least accessed menu, other than occasionally using the 'Low Boost' preset. It does however allow a fine-grained, subtle (when needed) control of frequencies. Shure puts an emphasis on that feature of the amp, and when exploring and toying with the custom EQ presets, it's commendable, and easy to understand why: If you won't be using an external DAC, this is a very accomplished way of matching the sound to your headphones and personal preference. It is worth noting however, that while the EQ can be used when plugged via line-in, it will "default" the sound to the capabilities of the unit's ADC/DAC, which can degrade sound quality if your source is superior.
The next entry in the menu is 'Audio', a more frequently visited area for me. Output gain can be changed here - Low/High, both of which are dead silent - the mentioned line-in input attenuation that helps prevent clipping from high output sources, and an "analog RMS limiter", which function to the best of my understanding, is limiting volume spikes.


The last menu, 'Utilities', controls technical aspects of the amp itself. The display's brightness and timeout can be adjusted, as well as its orientation (flipping the screen) and the volume pot's direction. Resetting and firmware updating is possible here as well, along with some info on battery health, its charge cycles and the unit's hardware info (which doesn't appear to mean much). One of my personal favourites is the ability to disable charging when the USB plug is connected, which appears to be a non-existent feature on a lot of DAC/amps and DAPs. This is particularly useful when plugged to a smartphone in DAC mode, as most battery-powered DACs I've tested so far, simply keep running (or charging) on power provided by the phone instead of using their own batteries, allowing about 3-4 hours of playback in the process.
In general, the usage experience feels like Shure knows their unit inside-out, and doesn't feel like there were two separate teams whose work was dumped in and merged at the last second (hi, Fiio).


(Limited) comparisons:
This is both fortunately and unfortunately my first foray into the 4-digit audio market, so equipment anywhere near the SHA900's price is rather scarce. Still, I figured it might interest people not into $100 jumps in their audio journey.
The first obvious comparison is to smartphones and laptops. In case somebody new to all this audio craziness is reading the review, with a decent pair of headphones/earphones from a respectable brand (Sennheiser, AKG, Shure, to name a few), the difference is day and night. In a quiet environment, you will hear a difference, and it will be enormous.
Unto some audiophile nonsense, the first first piece of equipment I have on hand is a Fiio X5/E12A portable stack. This is an IEM-targeted "great value/bang for your buck/competes with much higher priced" sort of thing, and one could argue that it can indeed compete with higher tier gear. The SHA900 however, sounds better in every single aspect, in both DAC and amp departments (except for the lack of hiss, which is pretty much the same). Long story short, it makes the Fiio stack sound like radio, answering the age-old question of whether double the money buys you "double the sound", which in this case, it actually does.
The second comparison is a more relevant one, and is a desktop Schiit Modi Multibit/Vali 2 stack. While I already mentioned the SHA900's DAC is a bit short of the Modi, in terms of the whole package, the Shure package presents a smoother, slightly more refined and more immersive listening experience. The cause for that, of course, is the Vali - while no slouch by any measurement, it doesn't quite portray the music in an effortless, airy presentation as the SHA900. While the various tubes help shape the sound to match particular genres and listening preferences, compared to the Vali, I find the SHA900 to be the jack of all trades - having the detail and soundstage of the stock 6BZ7, and the smooth, slightly warm lows of an EH 6CG7. Admittedly, not a fair comparison considering the price difference, but the fact a portable amplifier is able to outperform a very good desktop setup is worth mentioning.


Build, accessories and miscellaneous:
On the subject of construction, at first glance, it's a mixed bag: Modern construction trends dictate glass and metal in every millimeter of the product to give you that premium weight in your hand, yet the SHA900 is light, the buttons are plastic and none of them is particularly fixed to the unit (a bit wobbly). Once you turn the unit on however, the impression improves with the sharp-looking OLED screen, which doesn't suffer from the common washed under-saturated colours (all 6 of them ^^') of cheaper counterparts. Finally, examining the unit from up-close reveals an excellent build - there's absolutely zero mismatch between the layers, nothing popping out, and other than the feel of the buttons, the unit both looks and touches a match for its price.


The accessories of the SHA900 are, other than the cables, largely useless, which from experience appears to be a Shure thing. I can understand the rubber bands, but top to bottom, the cleaning cloth has a silky texture that instead of wiping your fingerprints, just smears them (unlike cotton); the airline adapter is useful if you're flying North Korean (i.e., deprecated); the volume attenuer sounds god-awful in any scenario I tried it; the 6.3mm adapter is very situational - if anything, I would've prefered a 6.3mm to 3.5mm cable adapter, as these plugs are more common with high-end headphones. Also, including a wall charger with a swappable plug is nice, except that there aren't any additional plugs provided. But the icing on the Should-Have cake is the lack of a case of any sort. At first I thought there had been a mistake at the shop I bought the unit from, as the KSE1500 set has one, but as it turns out, $1k is not enough to include one with the package. The SHA900 isn't exactly brittle, and personally I would have sufficed with faux-leather or rubber, but I still feel it's a cheap move on Shure's side.


Concluding remarks:
Welp, this has been my longest review by far, on my most expensive piece of equipment so far (which I hope remains that way). To sum this up in a paragraph, the Shure SHA900 is a subjectively exceptional sounding portable amplifier with an optional good-sounding DAC, has an accomplished UI with well-thought-of features and commendable attention to detail, and has an excellent construction to pack it all up. On a grayer side, one could ask for finer-grained volume control and the accessories are rather lacking.
More than once the subject of price has been a point of debate over this unit. All things considered, this is unavoidably a luxury multi-buck product: It doesn't sport a "great value" moniker, nor crams as many functions and features as possible into a single box. But in my opinion and personal experience, it doesn't need to, either. Instead, it achieves precisely what it's advertised to do: It costs close to a grand, feels like it, sounds like it, is built to standard, and ultimately, it's a product well worthy of the brand's reputation.

GermanMAESTRO - just rolls of your tongue. Little is said about the company around Head-Fi and I imagine most of their customers are companies too. Still, Massdrop had the GMP 450 Pro for $175 and I wanted a pair of good-sounding closed cans, so here we are.



My background and equipment used:
I'm your typical audio enthusiast: One whose friends think he's crazy for spending such money on headphones, but who will never pass the 4-digit mark unless there's something truly amazing on offer.
My equipment of choice is a pair of Shure SE846 earphones and Schiit's Vali 2 and Modi Multibit stack, which were also used for performing this review. The impressions are on a 100-hour+ burned-in headphones.

Sound impressions:
Before putting these on, the impression is that the isolation isn't going to be crazy, and unfortunately my educated guess was spot-on. For the advertised "closed design", the isolation is meek, and while it will block some high-pitched noise, both public transport and an "active" office easily pass through the cups. In fact, I'm pretty sure it's the same exact housing used for the open GMP 400, just with the grill covered, which brings me to the next issue.
The immediate impression on listening to some music with the GMP 450 Pro is that they sound muffled; the kind of muffled sound you get when you cover your open headphones with your hands. It seems unlikely to me that it's exactly what the company did, i.e. "close the headphones, leave the tuning", but it does seem odd to leave the tuning at that, as the result is a bizarre "taller than it's wider" soundstage. Quite a miss in my opinion, in particular when the sound has plenty of detail and potential.
On to some positive things, they do sound detailed: The layering is there, and while there's not much width to work with, instruments are spaced, sound full and don't take over vocals or themselves. A little surprise with these is that they actually sound a bit musical, which I wouldn't expect from such a flipped soundstage. In fact, it's the first pair of $200-300 headphones I listen to that produce at least some ambience, which I'll take over "emphasized highs/lows/crazy-detail" any day.

The sound signature on these is a bit... Standard. There's a slight emphasis on highs and a slighter one on mids, both of which help convey the feeling of detail. The bass however, is left alone and I find it lacking, particularly for dynamic drivers. While it is present, it doesn't extend low enough, and for neutral or cold sounding equipment I feel it impacts the listening experience negatively.
One last note about the sound of the GMP 450 Pro is that it's the first pair of headphones I find I like with some music genres, more than others. Call me crazy, but these seem to be more enjoyable with loud, fast and "busy" genres like metal and electronic, whereas jazz and acoustical don't feel as exciting.

Comfort, build, amplification and concluding remarks:
Not evident from the pictures, the construction on these is very solid. If 'built like a tank' can be said about any headphone, the 450 Pro will be it. While the look is unfortunately cheap, there are no bad screwed-in parts or anything that looks badly connected or half-baked.
Comfort however does feel much like it looks, and while the headphones are very light, the earcups are shallow and space is rather limited. The material isn't irritating, but it heats up pretty fast and keeps that heat in, which eventually makes prolonged wear a rather unpleasant experience.
Regarding amplification, they're pretty much what I expected from 300ohm dynamics: They don't sound awful from something like a smartphone or a laptop, particularly in loud environments, but for a proper bass response you'll need an amp. For what it's worth, the original Schiit Fulla drives them just fine, and I don't believe there's a need to buy anything above two digits for these headphones.

So, to put this review to and end, the GermanMAESTRO GMP 450 Pro are a mixed bag: Closed cups, but bad isolation; detailed and slightly musical, but muffled. Admittedly, after spending two weeks with them, you get used to the sound, and if that's your first pair of headphones at this price point, there's a lot to like. However, with the likes of the Hifiman HE-400i and AKG K702 going for under $200 on Massdrop, these aren't a priority recommendation.

There comes a time you're bored from your audio gear. You don't have a grand or two for a new set of ultra high end headphones to give you that fresh kick, and electronics costing as much as your current cans, make no sense.
Then comes Schiit Audio. They got new, they got cheap and they got an amp with a tube stuck in it for $170.
 
 
My background, experience and equipment:
I have and owned a few amps, but this one is the first tube variation. To me, it looked like poor man's equalization at first, but after some studying it appears the difference is being made at the analogue level and is more than frequency skews.
Anyways, I use the following gear for evaluations:
Headphones: Hifiman HE400i, Shure SE535, Philips SHP9500.
DACs: Schiit Modi Multibit, 1st gen Fiio X5, $1 DAC I got from ebay.
Amps: Fiio E12A.
Misc: 1st gen Schiit Fulla, Nexus 5 smartphone, Schiit SYS pre-amplifier.
Music: Metal (prog to extreme), jazz, electronic.
 
Sound impressions:
I've already known this amp doesn't sound "gooey" or warm as characteristic of tube amps, spoiling the surprise, but was still pleasantly impressed on first listen: Detailed, accurate and transparent, with a little extra on the highs. In fact, it can be debated whether it's too transparent for its own good, not because of it being a bad thing, but because of the expectation from a typical tube amp sound (which I only ever read about, of course).
Admittedly, my previous amp was a portable Fiio E12A, so in terms of price the Vali 2 should outperform it, and as expected, it walks the park with it. The sound is open, more detailed, the vocals are great, the bass has a texture (new thing for me with this) and overall the listening experience feels more immersive.
One great achievement of this amp for me is that I sometimes hear new details in songs I'm familiar with. Whether it's caused by the small bump to the highs with the stock 6BZ7 tube or the overall package, I do not know (the EH 6CG7 pronounces the phenomenon less), but it's these things that are worth upgrading for.
 
Unto tube rolling, there are a lot of tubes compatible with the Vali 2, from a wide variety of types and prices (starting at $15 and going well above the Vali 2 price), each having its own sound signature.
Before dwelling in, I've set a two point mantra on the subject: Don't fix what ain't broken; be mindful of diminishing returns. I.e., when I'm listening to a perfectly functioning amp that sounds fine to me, I see no reason screwing things up. Which was true until I got a pair of Hifiman HE400i and had to tame the treble.
Long story (browse Tube Depot) made short, $15-25 is what I was willing to pay for 1940s technology plugged to a $170 amp. After consulting the dedicated tube rolling thread, I got an Electro-Harmonix 6CG7 and learned what "tube amps are all about".
Compared to the stock NOS 6BZ7 (which costs about $4, and sold for $10 at Schiit, by the way), this slightly fatter, taller offering sounds warmer, smoother, more detailed on the lower end, but most ominously, more pleasant. On the same difficulty of explaining "musicality", the way I describe this is it being the audio equivalence of drinking just enough to feel the effect. However, with the EH 6CG7 you do get a narrower soundstage (unless you consider this intimacy), less detailed highs and a bit less air and realism. In the end, tube rolling is a very subjective experience.
Ultimately, the tubes should match your headphones and personal preference, which is both good and bad: Appreciate the choice, not so fond of the price on the "tube starter kit" and the fact that you won't know you like them until you listen to them. All that before going "high end" (like 2-digit prices? too bad).
 
In regard to usability, the amp comes with a gain switch and pre-amplifier connectors. It's been mentioned in a review here that the pre-amp is meh, and at first I did feel the sound is a bit muffled, until I rigged it into the Schiit SYS and did direct comparisons, with the output sounding exactly the same. Admittedly, my speakers are a ten years old 2.1 Creative set that cost about $60 at the time, but I know their sound inside out, and if there is a difference, it's a very subtle one.
As for the gain switch, the low gain does its job for (almost) silently driving IEMs. The Shure SE535 can pick up a bit of noise depending on the tube, but once the music is playing, it's not a problem. I should mention that extreme caution is advised when listening with IEMs, even on low gain. The Vali 2 appears to have preposterous amounts of power for efficient headphones: Even on low gain, the SYS set to 9 o'clock, 10 o'clock on the Vali 2 is enough to make them very loud. Additionally, the mute relay in the amp is either malfunctioning or just not working as it should, as after long shut-down periods, the amp emits a loud "pop" through either the pre-amp or headphone jack, soon after starting. The volume of the pop does not correspond to the pot position, and needless to say, if you have your IEMs plugged and in your ears, you're in for a world of hurt.
 
Miscellaneous and concluding remarks:
Aesthetically, the Vali 2 is a babe, as long as its Atari 5200 power adapter is hidden from plain view. The design is clean, no nonsense, and you get a bonus if your tube has a healthy glow.
It should be noted that the amp comes with no cables, or adapters, which I personally find lacking, particularly when a lot of people stack their Schiit gear. Sure there's Monoprice and the likes, but I'm sure including a cable won't kill the business.

Anyhow, to sum this all up, the Schiit Vali 2 is a fun, relatively affordable, little all-arounder. Unpack the box and get great sound, not a lot different than a good solid state amp. Or, go adventurous, buy a bunch of tubes, have a ride on the aural roller coaster and discover what audiophiles and Russian fighter jets have in common.

I'll keep this relatively short as the HE400i has over 20 reviews here, some of which are very detailed and some that contradict others. This is just my 5 cents on the matter.
 
I think @jerg summarized it perfectly in his review, that these are a "compromise between musicality and technicality". On one hand, they are detailed and accurate, have great separation and for acoustic music, there's good layering. On the other, listening through them simply isn't immersive enough, as if they are too detailed, soul left outside the box. It's kinda hard to explain in words, but if you ever get the chance to listen to a pair of Shure SE535 (*) or something with a similar audio profile, you'll understand what I'm talking about. Imagine the audio equivalence of drinking just enough to feel the effect.
(*) My listening (and evaluation) mule for the past 5-6 years.
 
Other than musicality, my second and final con on audio with these, is the treble. It's too extended, causing things like cymbals to sound too distant from the rest of the record (think one floor above). Some call it separation, I call it "the thing that's wrong with half the cheap headphones I listen to", except the HE400i ain't cheap. A lot of companies seem to do that as it adds sparkle and detail (I guess?), but personally, I'm not a fan.
 
Unto actual usage, these are pretty easy to drive from anything. Smartphones, Fiio amps, 1st gen Schiit Fulla, no problem.
On comfort, the pads and headband are very nice and comfortable, but the grip is very tight. I've been looking around for a solution on Google without avail, till I got tired (and pissed) and took the "manual" approach: Bent them myself at 5 points across the upper steel gate, now it's just fine (the 2 L bends, middle, and half-way through to the middle).
I read about these having some issues with the cable and Hifiman mentioned on their website about swapping them. For what it's worth, I got the new cable, and no complains. It's thick and conductive, really all I have to say. The 6.5mm adapter is crap though, had connection issues so I threw it to the bin (having another 5 laying around).
 
Lastly, Hifiman states in the manual that "to obtain optimal performance", these should be burned in for "at least 150 hours", constantly. Subjectivity aside, this is, by far, the dumbest remark I've seen on any headphone, from any manufacturer. Just think about the prospect of, well, buying a pair of $500 headphones, eagerly anticipating them, finally getting the package and then, "welp, here they are, let's just put them there playing and wait another week". By now I imagine I passed the 150 hour mark, and frankly? I don't remember how they sounded a week ago in comparison, to be bothered with. If it wasn't important enough to burn them during production, this can't be too meaningful at the customer's hand.
 
To close the review, you might be wondering why the 5 star rating. Simple: Supposedly these retail for $450, but occasionally they will go as low as $250, and for that price, it's very impressive value.

Equipment used: Schiit Modi Multibit and Vali 2.

Once upon a time I played an online game and found myself in need of both a microphone, and unrelatedly, a new pair of closed headphones for general music listening in the office. Seeing as gaming headphones go from $50 to $250, I figured, in the Hi-Fi world, the $200 mark is an excellent entry point, so here we are.

If you're looking for a pair of headphones for music, I'll save you the time on reading the entire review and mention right away that these sound bad. Not in the sense of "lacking A/B/C", but in the sense that music just doesn't sound right through them. However, for the relevance of the review, I'll be looking into them from the target audience point of view (young and/or hardcore gamers), and cover the following:

1. Feeling during fast-paced games - communication, comfort.
2. Control, customizability and the software suit.
3. General usefulness of the package.

 

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Package & Externals:
The package is a flashy affair with a layered paint job, and a box-within-a-box packaging. The headphones themselves are partially sealed with some nylon and removable stickers, to further impose the feeling you're unwrapping a fancy piece of gear. Dig in further, and underneath them you'll find another opening, revealing a compartment with a bunch of cables (phone adapter included), a "sound card" with USB, audio-out and mic-in jacks, and a user manual. The manual is pretty straight-forward if not a little dumbed down (the [THIS IS CORRECT/THIS IS INCORRECT] pictures format).
 
 
The headphones cable is, unfortunately, permanently attached, so no replacement when that breaks neither any attempts to improve the sound at the hardware level. You do get an extension cord, so (permanent) detachment as a result of an unintended too-long tug is unlikely.
As for the headphones themselves, they're surprisingly true to the pictures and built well with no flimsy parts, except for the retractable mic, which feels a bit loose. Parts intended for fidgeting with, such as the volume ring, have a rubbery strip on them and the cables are nice and grippy. While I'm not a fan of LEDs in any personal audio gear (exactly who you gonna impress playing alone in your room?), the lighting is sharp and uniform across the whole cup.
 

Interestingly, the headset also has an audio jack to connect an additional set to it. This appears to work well, as well as allow audio input, although sound quality on the 2nd set is slightly degraded by the citcuitry.

Control:
At the "Plug & Play" level, you get a nice set of features straight out of the box. Volume is controlled by a ring located on the right ear cup, with plenty of swivel for fine tuning, and a similar switch-oriented ring for unmuting the microphone on the left cup.
The mic itself is retractable and flexible to allows positioning relative to your mouth, and doesn't move around on its own. It also has another white LED in it that lights up when it's muted (opposed to listening), which at first I thought was a bug, then realized I'm being distracted by the light. When retracted it's hardly noticeable, so overall a nicely implemented feature.
 

Steelseries does advise you to download its management software, which is also used to update the headset's and sound card's firmware. The software allows you to control the LED colours, DSP, microphone audio modification (noise reduction, compression) and reverb (which doesn't seem to work, even on its loudest settings). It can also be configured to be "game aware", changing the LED colours based on games being played and even on actual game events (such as HP/Mana). Use cases for the feature are rather specific and it should be noted that games require integration with the software to work.
 
Gaming & Comfort:
To comment on the actual gaming subject, let's first define who are gamers, and what one might want. I see myself as a semi-hardcore case, on my free time playing some single-player titles (TES, GTA), some MMO (Runescape) and high-ranked MOBA (LoL, D+). As the Siberia 650 is priced towards the higher price range in the gaming headset category, I would expect most of the following:

1. Sound isolation.
2. Wide soundstage.
3. Clear voice input and output.
4. Short-to-none setup time.
5. Simple use and control.
6. Comfort and no wear fatigue (heat).
7. Reliability (no bugs, no skips).

 
Addressing the requirements by order, the sound isolation is only barely plausible. On medium volume levels, I can hear keyboard strokes, as well as the AC behind me when it's on, and wearing the headphones with glasses leaks in additional sound. The Steelseries Siberia 650 product page actually shows a gaming stage above the isolation remark, which I personally find as plain misleading advertising, let alone quotes from professional gamers using them on stage: The noise output of a few hundred hysterical teenagers (at the very least) is far too much for these to isolate from.
As I mention in the Audio Quality section of the review, the sound is very far from stellar. However, the headphones do appear to bring forward voice and vocals in a clear and accurate fashion, with the microphone recording very well too. The software also reduces noise by default, and so far I haven't heard complaints from fellow gamers over voice chat.
Setup time is practically nonexistent as there's no hinge on the headband to position, and the headphone holds itself well on the head without slipping off. As for comfort, it's a mixed bag: While the padding does not keep in heat and looks impressively large in pictures, in reality, the cups are shallow enough for my ears to hit the barely padded plastic, and for whatever "memory foam" cushions they might've used in there, it feels like simple sponge and that there's not enough of it. While it's less bothersome in attention-hungry online gaming, casual, relaxed games may find you being bugged by the headphones bulk sooner than later.
 

On reliability, I have not encountered any disconnections, noise, skips or glitches in the sound or microphone. The only oddity I ran into was with the sound card, sometimes not connecting well with the headphone cable, causing the left ear cup to mute. The issue can be fixed with a bit of fidgeting, but I find it increasingly harder to adjust and get the feeling that eventually the USB input plug will someday fail.
Update (11-Dec-2016): The sound card has indeed failed and the unit was sent for repairs. Half a point off for that on the overall scale.
Update (22-Dec-2016): The replacement unit's microphone isn't working (brand new box). Oddly, the earpiece sound quality is slightly better, though I still stand by my original impressions.
 
Audio Quality:
Well, this is Head-Fi, and unfortunately these are the type of headphones the community tends to open whole cans of whoopass on. I should mention that I've never listened to the Beats or Skullcandy brands, but with this pair I have the feeling I'm getting the general idea...
Starting with the nonexisting tonal balance, the immediate impression is listening to full-size speakers in the bathtub. The sound is undetailed, muffled, with inflated upper bass and highs that clip at about 12k. Low bass is nowhere to be found either. Now, I hold no grudge to headphones lacking frequencies here and there, but these simply distort them. My mindset blind-buying these was that if the $5 VE Monk can sound well, a $150-200 set can't sound worse, but here we are.
Initially I thought there was either a bug or the USB-to-3.5mm adapter was horrible, as I've been plugging them to an amplifier. Sure enough, the Steelseries software immediately suggested a firmware update when I plugged them to the bundled sound card, and after the update (or just by default) a DSP automatically kicked in, which amplified the highs and removed the bathroom soundstage. This is, of course, isn't a real fix and I would've preferred to just have the option to modify the sound myself.
Unto the the subject of equalization, the software presents one of the most bizzare EQ presets I've yet seen: At the very least, one would expect "Bass" and "Treble" presets, but instead there are things like "MMO", "Performance" and "Explosive Action", all having graphs that make no sense and heavily distort the sound further. Funnily enough, there's a "Music" preset, which is a V-shaped graph. At some point I tried building one myself, but for all I hear there's little I can salvage from the headphone's cheap drivers. An argument can be made here, that some gamers like boomy, flashy sound, but I beg the differ, due to the simple fact that games I play regularly suddenly sound unfamiliar and distant, requiring a re-adaptation period.
 

One of the key selling points for these (and apparently a lot of other gaming headphones) appears to be 7.1 Dolby. This is, of course, done at the software level, which I was skeptical about to begin with. Sure enough, turn it on in the software and you'll hear what appears to be an attempt to position frequency ranges at different points in the soundstage, the execution of which is not only miserably useless, but even further muffles the sound in an attempt to achieve an effect I cannot define: Open-world games are not more immersive and shooters and MOBAs simply have their sound badly positioned.
As I mentioned, I initially connected the headphones to an amplifier for a quick test (Fiio X5+E12A, to be exact), while the package includes what appears to be some sort of USB DAC/Amp that has an headphones-out jack. Obviously there's no point comparing an (at best) $10 tic tac box to anything Hi-Fi, but from plugging some proper earphones to it, I can tell it falls short of a Nexus 5, which is a shame as well. Either way, plugging the Siberia 650 to a good source may slightly improve the resolution and detail, but it won't change the problematic frequency skew.

Summary and Alternatives:
To put the review to a close, let's recap.
The Steelseries Siberia 650 is a "gaming headset", which does well what a gamer might expect and then adds some: Great control tools, good build quality and voice transmission. The Siberia 650 is not, a "professional headphone", and has bad sound quality, low isolation, lacks long-session wear comfort, and for whatever minimal audio performance you might think $150-200 will land you, these will set a new low standard in that regard. The product page quotes these as "One of the best PC gaming headsets", from which - the music lover point of view - I understand that the PC gaming headset market is saturated mostly with crap.
If I had to suggest an alternative, the obvious no-brainer route is getting a proper set of headphones and a mic that has a mute button, the latter costing about $10-15, leaving you a lot of choice room for proper closed headphones. If you still need something with a mic stuck in it, and a paint job, Sennheiser has its Game Zero model, which is a small investment up from the Siberia 650, or go for broke and get the Beyerdynamic MMX 330, which I imagine are the best-sounding "gaming" headphones out there, probably by far.
As for the Siberia 650, I simply cannot recommend them unless you get them at least on a 60% discount.

I'll be honest, after reading a few chapters from Schiit Happened and the hilariously honest, bulls***-free product descriptions and FAQs on their website, I just had to buy something from them. And what does a consumer buy when he wants to buy stuff for the sake of buying? Simple, the cheapest product on the catalog, of course (which produces sound on its own).
 
Evaluation equipment and quick preface:
Shure SE535, Philips SHP9500, a Nexus 5 smartphone and a desktop computer (VIA VT2020@Gigabyte Z77-D3H, but let's face it, most of them sound the same).
The evaluation and ranking of the unit is with regard to its price and advertised function.
 
Sound:
As far as I'm concerned, this little thing is aimed at replacing the crappy little headphones-out of your computer, laptop or stationary smartphone (*). In that regard, the Fulla is a great success. Firstly, the sound is much cleaner, fuller and more extended. If you're a critical listener (i.e., don't own Beats or Skullcandy), you will hear more detail in your music and some records might unveil a bit of ambient detail (I call it musicality, but whatever) - listen to Daft Punk's Random Access Memories and Symphony X's Underworld, and decide for yourself. Secondly, you might argue that some smartphones have excellent sound, but I've yet to witness any coming anywhere near a standalone DAC (iPhones included), let alone being able to properly drive anything power-hungrier than IEMs, which brings me to the next point.
The Fulla has plenty of power, which I feel is great for driving common full headphones (anything under 150 ohm), both in terms of sound quality and output volume. For IEMs however, it has too much power: The more sensitive ones have a pretty noticeable hiss which is audible in music that's considered quiet, and if you crank the volume up, an odd beep begins to be audible as well.
 
From an audiophile point of view, and I'm just mentioning it here for completeness because I don't believe the Fulla is aimed at audiophiles, I find the unit lacks a bit on both ends of the spectrum. That is, it does not produce a low enough bass, nor the highs are open enough in my opinion. Additionally, I feel both ends, bass in particular, lacks detail and smoothness. That's not to say the overall experience is bad, it's just that, say, the HiFimeDIY Sabre DAC ($42) produces more of the bass I described (and slightly less detail and highs)(**). A matter of tastes and compromises, all in all.
 
(*) Office/home listening.
(**) I coupled the Fulla with a Fiio E12A for that conclusion.
 
Package and externals:
I like it. Cleverest use of cardboard I've yet seen, with the only drawback being that it might leave a mess once you take it out. Comes with a short USB cable and a questionable carrying bag. The reason I call it questionable is because the Fulla has jagged edges and I'm pretty sure that if you use that bag often, it'll be shredded to bits sooner than later.
Aesthetically, the Fulla looks great, being this tiny silver-gray thing with folded metal and a volume knob. The materials look and feel good, although, as I mentioned, the edges are jagged to a point of possible injury and the volume knob wobbles - not that it's loose, it's just that the board underneath appears to be not 100% stationary.
 
Bottom line:
This thing is aimed to improve a default setup you get with a computer/laptop, and it succeeds with flying remarks in terms of sound quality and function. If you move around a lot and not fussy about high-end headphones, then the Fulla is a perfect companion. Particularly for full headphones (all sorts of mid-range AKGs, Shures, Sennheisers), it's an easy recommendation. $80 well spent.
For pricier headphones, it can leave a craving for more, particularly if you already own a fancy DAC or amplifier at home and just buying this for portability.
Finally, for earphones and IEMs, I'd advice more caution in regard to how sensitive your phones are, and how sensitive you are to hiss. Shure earphones and old fashioned Jazz, for instance, might be a no-no.
 
On an off-subject note, I've read reviews saying the Fulla is a good first step in the foray into the audiophile world. I won't rule it out, nor I'm going to argue with anyone, just keep in mind this is an all-in-one purpose-guided product. It will not suit everything you throw it, nor is it upgradeable.

This cable appears to aim at two very particular listening scenarios:
1. You're lying in bed motionless.
2. You're sitting dead-still at your desktop.
Why? Because every single movement of this cable, every little touch, will reverberate in your ear drums like a cannon blast. I did not know what 'microphonic' means until I used this cable, and unfortunately this is something one should not underestimate. How bad it it? It's enough for your DAP, not the cable, the DAP itself to be lying 40 cm from your keyboard, to hear keystrokes. It's that god awful.
As for ergonomics, I won't say it's plain uncomfortable to wear, but it feels unfriendly wrapped around the ear and gives the feeling of a steel wire wrapped in an insignificantly small sleeve of rubber. A big step down from the original cable. The elastics of the cable are pretty bad too and it feels small and stiff to bend.
Another annoyance is the cable's length. I know it's a plainly advertised feature (and thus should not be a surprise), but you don't realize how short it is until you use it. While it's fine when your player sits in your pocket, it's simply too short to be played from anything further than that. Like having a DAC+Amp combo playing from your backpack? Too bad. Unless you're sitting with it on your lap, it simply won't reach.
 
On the bright side, listening through the RC-SE1 does improve the sound, quite noticeably. After listening to the same earphones for 4 years, I had no problem recognizing the difference. Everything becomes slightly more spacious and detailed. The sound gets more separation and little new subtleties pop up in music you're familiar with. It won't give you the 'like listening to a new song' effect of buying new headphones, but as an upgrade to mid-high-end IEMs, the $30 is a worthy bang for your buck.
 
Anyways, to sum things up:
This is my 5^th Fiio product and by now I'm used to the mechanics in which they excel at something (usually the sound quality), perform poorly for mostly everything else, and suck hard at a key feature of which you're in dire need.
I've had this cable for about half a year, and eventually downgraded back to the stock cable that came with my in-ears. Its core functionality is intact, a proven test in sound quality, but as far as usability goes it's an absolute miss that quickly negates the advantages.
 
Test setup: PC >> Fiio X5 >> Fiio L16 >> Fiio E12A >> [RC-SE1] >> Shure SE535.

I'll keep this short since, well, it's a cable.
I got it as part of the X5 stacking kit, to pair it with an E12A, replacing the original cable that came in with the unit (the L8). I imagined it's just going to be a pretty cable, but I was pleasantly surprised to actually hear a difference.
In a nutshell, compared to the "generic" audio cable, what I subjectively heard:
1. The highs became more audiable and clearer, but not fatiguing. I'm very sensitive to the latter so I guess that's an accomplishment.
2. The overall sound became slightly more detailed.
 
On the bad side, while the actual gold and silver connectors are gorgeous, the cable itself has a semi-transparent sleeve, which kind of looks smudged. Additionally, similar to Fiio's headphone cables, the silver plug can be screwed in and out for some reason. That's not really a drawback (I really don't know its functional purpose), but I thought I'll mention it here anyway.
 
To sum this up, I'm actually aware cables do make an impact. The improvement in audio quality with the L16 isn't day and night, but it's there and it's not hard to notice. I know that some companies out there are selling similar cables, sometimes for hundreds of dollars, and they aren't ashamed to claim you'll hear a difference worth that sum.
For the L16's price though, I believe you get your money's worth: A subtle improvement in sound quality without a hole in your pocket.
 
Test setup: Laptop USB > Fiio X5 > [L16] > Fiio E12A > Shure SE535.