Schiit Audio Vali 2

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 originally bought my Schiit Vali 2 and Modi Uber to listen to music while surfing the internet. After a tube upgrade to a Telfunken 6922, it sounded great with Schiit short ICs . About three months after I bought the stack, Good old Schiit comes out with the Modi Multibit. I ordered one and sold the Modi Uber. I initially started with an Audioquest Carbon USB cable, but have been trying Wywires cables in my good armchair system with Yiggy and Ragg fed by an old Oppo 83 Blue Ray player. I had already tried several other 6922 varients and at last settled on Russian Reflector or Voskhod 6H23P tubes because they added more life, realistic tone and greater frequency response. With the right tube, now the Vali 2 sounded better than my original Lyr after being tube rolled. 
Last week I completed the Vali 2/Modi Multibit system with Wywires Silver ICs and their Platinum USB cable. As you can imagine, the cables cost a little bit more that the Schiit stack. System now has it all. Bass definition, PRAT, soundstage, realistic tone. Headphones used in this evaluation: Mr. Speakers Ether -C 1.1 with Wywires Red headphone cable and Seen HD 600s with Toxic Cable Silver Poison.

 
For a long time there has been a fascination with cheap tube amps on Head-Fi. For many years Little Dot and Darkvoice had the lead. The last small tube amp I reviewed was ALO Audio's now discontinued PanAm. It was a unique amp in that it had an optional 12V battery power supply which made it (trans)portable. It also had a 24/96 capable DAC built in and used very cheap tubes.
 
Like the Vali 2, it was a hybrid, that is a tube voltage gain stage with a solid state output. The PanAm was pretty good with high-impedance headphones but struggled a bit with low impedance and low sensitivity planars. Schiit Audio original Vali used sub-minature tubes originally intended for hearing aids before the advent of the transistor. Those tubes, while capable of sounding good, could be pretty noisy, and in Schiit Audio's inexpensive aluminium cases would ring like crazy if the case was tapped. They also had a high failure rate (at the factory) making the amp a pain for the company. 
 
With the Vali 2, Jason Stoddard gave up trying to keep the tube in the case and relented to having it stick out of the top, negating the need for tricky thermal management. He has also selected a tube for which there are a number of types which can be used its place.  After solving the issue of the multiple voltages required for the circuit via the use of a dual-voltage transformer, Schiit Audio managed to keep the price down to a crazy low $169 by keeping everything simple, from the basic chassis to using the simplest parts. 
 
The great irony of my review of the Vali 2 is that it came about from buying an Yggdrasil. I asked Jason if I could get a review sample of the Vali 2 at the same time as I bought the Yggy, as I wanted to see if it was really worth the hype that was inevitably going to surround it.
 
At first plug-in (via the Yggdrasil, none the less!) the sound was a little strained, and in low gain mode didn't really wake up the bass of my MrSpeakers Ethers. In high gain mode after a day of being left switched on the Vali had come good and started showing some serious potential, punching way above its price point. With more delicate and calm music it was a joy to listen with, throwing a good soundstage with either the relatively easy to drive Ethers or the Sennheiser HD800s.
 
Demanding music started to show some strain in the performance. Horns in classical and jazz music became a bit shouty and harsh whereas they would come out more effortlessly and clear from my (very vastly more expensive) Studio Six, or somewhat more expensive Audio-gd NFB1AMP. Similarly, the music would start to blur whenever the music became even slightly complex.  Even so, the bass punch was impressive with either pair of headphones and it was, for the most part, only when I compared the performance to more expensive amps that the Vali's short-fallings became apparent. 
 
I sure as heck didn't feel like I was listening with a $169 amp, more like one that was at least triple the price, and I'd readily forget which amp I'd plugged my headphones into while it sat on my desk. To up the ante I plugged in the HiFiMan HE1000s. I was surprised to get a similar degree of performance with them as I had the Ethers. Not what I was expecting at all! Not only that, but a fair bit more detail retrieval than I had expected. For example, the slight flatness in the sound of the remaster of Jack Johnson's Bushfire Fairytales album was just as apparent through the Vali 2 as it was through the Studio Six, both plugged into my Yggdrasil. There was still some degree of looseness and blur to the sound compared to the better amps, but knowing that I'd have to spend 4-6x the Vali's price to better that I was impressed.  
 
Since the Vali's output impedance in low gain mode is a usefully low 1.2 Ohms, I decided to try my Roxannes in them. I was rewarded with a pretty good and clear result, along with some quite thumping, if slightly out-of-control bass, with only a bit of sibilance in the treble on Morphine's Buena while the Yggdrasil's lovely mid-range vocal reproduction was kept sufficiently pure. Quite a good result, even if the Vali 2 is not the amp I'd choose as a first preference for IEMs, as the various DAPs and amps I have on hand are better controlled and more precise-sounding. However, the Vali wins for entertainment value, if the DAPs do for purity of sound.
 
The amp is rather like a crazy kid who had decided to try and pull off something way too crazy, but gets away with it. Listening with the Vali 2 is rather like being slightly tipsy. Everything is more amusing, if imperfect.
 
To make things more interesting, I grabbed a couple of tubes off eBay to see how they'd perform. Jason has quite rightly pointed out that one could very well end up with tubes costing more than the amp, and since all the cables I have retail more than the amp does, this isn't a surprise to me. First to arrive was an Amperex 6922 "PQ". The Canadian 6B7Z/6BQ7A that the Vali 2 comes with is quite forward and a bit aggressive, causing some people to complain about sibilance, but still very good. The Amperex in its place gives a more open and relaxed presentation that I didn't feel gave up any precision.  A Matsus?ita 6AQ8 that I dropped in seemed to give similar improvements to the Amperex, if a touch more relaxed in comparison. On the other hand, a Matsus?ita 6FQ7 was warmer-sounding with more bass, though unfortunately a bit less dynamic and a touch more flat-sounding than the other tubes, possibly due to the slightly relaxed treble. Overall, the expensive Amperex PQ, as per its reputation, wins for me, but the other tubes, quite a bit less expensive, are better value.
 
I gave the Vali 2 a run as a pre-amp to my ADAM ARTist 3 active speakers. The result was pretty straight-forward, a narrower in presentation compared to everything else I have on hand that is more expensive but at least it does the job. 
 
There isn't really much bad to say about the amp aside from the lacklustre pre-amp functionality. The worst thing about Schiit Audio amps are the sharp corners on the sheet metal of the case which can scratch people and things if one is not careful. With the Vali 2 the only inconvenience is the huge and heavy wall-wart which is quite big and bulky and will crowd out adjacent sockets on your power strip.  The good side to that is the din plug for the power, being uncommon, you aren't likely to plug in the wrong power supply if you have other wall-wart-powered devices around.
 
For ideal results, one would want to use the low impedance setting for planars, but if they are insensitive, as my HE1000s are, that limits the volume output significantly. 
 
The primary thing I look for in a product nowadays is: Do I want to keep listening with it, despite having a wonderfully tuned system to listen with? With the Vali I did, which says a lot.  What is most amazing is how the Vali manages to keep one entertained yet keep it together at the same time, compromisingly only a little at either end of the spectrum, and yet only costs $169. Put it together with a Chord Mojo and a nice tube off eBay and you have a <$1k rig that will power even high-end headphones well.
 
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Links:
 
Vali details from Schiit Happened:
http://www.head-fi.org/t/701900/schiit-happened-the-story-of-the-worlds-most-improbable-start-up/9000#post_12153256
 
Tomb's post on tubes:
 
http://www.head-fi.org/t/790828/official-schiit-vali-2-thread/225#post_12178839  

 

1. 6BZ7 - Nothing but "Different filament voltage"  (DO NOT USE)
2. ECC88 - 6DJ8, 6N23P*, CV5358 (Close or identical), 6922, 6922WA, CCA, CV10320, CV2492, CV2493, CV8065, E88CC, E88CC01, ECC868 (Different rating or performance) - You can try all of these.
3. 6922 - 6922WA, CCA, CV10320, CV2492, CV2493, CV8065, E88CC, E88CC01, ECC868 (Close or identical), 6DJ8, 6N23P*, CV5358, ECC88 (Different rating or performance) - You can try all of these.
4. 6DJ8 - ECC88 (Close or identical), 6922, 6922WA, CCA, CV10320, CV2492, CV2493, CV8065, E88CC, E88CC01, ECC868 (Different rating or performance) - You can try all of these.
5. 2492 - This is actually CV2492 and will not work in the search criteria unless you use the "CV." 6922, 6922WA, CCA, CV10320, CV2493, CV8065, E88CC, E88CC01, ECC868 (Close or identical), 6DJ8, 6N23P*, CV5358, ECC88 (Different rating or performance)

 
 

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