VTV AMPLIFIER Stereo Purifi Audio 1ET400A Amplifier

(21 customer reviews)


SKU: 27564 Category:


NEW Stereo VTV Amplifier with Purifi-Audio 1ET400A modules.  


See Purifi-Audio DATASHEET here.

VTV Purifi Manual here


This is a brand new amplifier featuring:


—Multiple Input Buffer Options

The VTV Buffer option:

SPARKOS LABS SS78 & SS79 DISCRETE VOLTAGE REGULATORS provide power to the Op Amps and amplifier module.   The Sparkos Labs SS78 and SS79 Discrete Voltage Regulators bring ultra low noise and fast transient response to VTV input buffer board. Customers notice low level listening ability, far superior 3D soundstage and high frequency details.  The VTV Custom buffer accepts industry leading discrete opamps from Sparkos, Sonic Imagery and Weiss—-all in stock and available at VTV. 


—Hypex SMPS1200A400 power supply (this is the power supply used by Purifi to demo their modules)

—fully balanced design

—EMI/RFI filtered AC inlet

—MOGAMI input wiring standard


—Heavy, custom designed aluminum case with blue LED pilot.  (LED may be dimmed or shut-off by switch)

—Silver-coated speaker output wiring with TFE jacket

—2 Year Warranty

–12.25″W x 13″D (not including speaker posts) x 4.25″H  W:14 lbs

Additional information

Input Buffer

Stock Hypex Factory Buffer, VTV Amplifier Custom Input Buffer w/o OpAmp, VTV Amplifier Custom Input Buffer w/ Sparkos Labs SS3602, VTV Amplifier Custom Input Buffer w/ PR Sparkos Labs SS2590 Pro Opamp, VTV Amplifier Custom Input Buffer w/ PR Sonic Imagery Labs 995FET Pro Opamp, VTV Amplifier Custom Input Buffer w/ PR Sonic Imagery Labs 990EnH-Ticha Pro Opamp, VTV Amplifier Custom Input Buffer w/ Sonic Imagery Labs 994EnH-Ticha Pro Opamp, VTV Amplifier Custom Inout Buffer w/New ClassD MKII Opamp, VTV Amplifier Custom Input Buffer with OPA1612 Opamp, VTV Amplifier Custom Input Buffer w/ PR Weiss OP2-BA Opamp

12V Trigger


Binding Post Option

Default Binding Post, SPEAKON, WBT-0703Cu NextGen, WBT-0702.01 TopLine

21 reviews for VTV AMPLIFIER Stereo Purifi Audio 1ET400A Amplifier

  1. Greg (verified owner)

    Beautiful clean sound. Much tighter bass and clearer cymbal rings on my Vandersteen speakers than previous amp.

  2. Alan Huth

    Really great sound! Very fast service and Warren answered all my questions. He was very patient and helpful. And his prices are great. This amp is a steal. Have you seen the reviews on AudioScienceReview? You could argue it’s as good as they get without spending many multiples of this price.

  3. anonymous

    The purifi stereo amp is absolutely stunning for the price. It has depth and detail along with clean power such that the cost per watt is truly incredible. Absolutely the best 200+ wpc amp I have tried easily beating the PS Audio and Mytek high power class D offerings which cost double.

  4. Greg G. (verified owner)

    Really enjoying this 1ET400A amplifier! Very smooth, detailed sound. Effortlessly driving a pair of Totem Hawks and Focal Aria 906’s to whatever level I need. Warren is very informative and responds quickly. These amps are a great value – industry proven components and a quality chassis. I will be buying another unit in the very near future!

  5. Michael P. (verified owner)

    So, I have been in audio since 1985 and before when my dad came home from Vietnam with a Sansui 8, dual 1219, and an Akai reel to reel. Over that many years I have gone through a myriad of amps speakers and sources. I am intimately familiar with Class A and AB amps. I have been following the development of Class D for years. I decided to take the jump and look for a good amplifier. I checked out Mytek, Micromega, and Nord. All excellent Class D amps with prices to match. I came across VTV audio and Warren Coleman.
    I did what PhDs do, I researched everything about Class D and learned that Purifi provides their amp modules to the NAD Masters series, Mytek, and a number of other OEMs. I spoke with Warren several times and he explained how Class D works and the buffer modules. I was sold. No hype, no bait and switch, just honest sincere answers. I opted for the Purifi Audio 1ET400A Amplifier with the Sonic Imagery 995fet pro opamp.

    The unit arrived quickly, and I let it “burn in” for a few days and hooked it up to my Parasound P5 pre to Acoustic Energy AE 309s. My sources were my laptop playing Tidal to a Woo Audio WDS-1 non-oversamplefier DAC. I played low volume as the amp puts out 400 wpc. I eased the amp in. Immediate observation is the amp transformed the 309s. Bass output was better, deeper, precise, a revelation. Knocked me on my butt! I did not know the speaker had it in them. The tweeter was about the same in projection with much better presentation of cymbal crashes and brushes, highly detailed and the decay was much better. So, we get to the heart of music, the midrange frequencies. I heard the last knock against Class D was an issue with the midrange; the frequencies would project with a “hollowness” to them, not light, but like a shell without filling. The midrange from the VTV was detailed, succinct, and layered. The frequencies were layered, imaging was much better. Suddenly my M&Ms had filling, my pie was bulging with sweet cherry filling and detail and instrument placement in the field was greatly increased. I was in awe of what my speakers were doing.

    Next, I hooked up my brand-new Fyne Audio F501s. I played a few songs which give me a solid idea of how components do. First, 2Cellos version of Benedictus. The cellos sounded LIKE cellos, the decay in the strings was monstrous. The 501s seemed to float…er, the music seemed to float. Next, I listened to Leonard Cohen’s version of Hallelujah. Cohen’s voice in the rendition changes immensely from relaxed, soft, and clear to a strained, gravely, and deep inflection. He sounded so glorious and clear. Jeez, the F501s are one hell of a speaker! Lastly, I listened to Kinna Grannis rendition of “Can’t help falling in love with you” from Crazy Rich Asians. The kick of this song the way she sings it, the dead air that hangs out in your room. Black is what I heard and saw…BLACK, a void in space. The VTV was absolutely clean and quiet. I kept going, hearing songs for the proverbial first time as professional critics like to say. Muse’s Hysteria is an acid test for bass control and projection and the VTV nailed it, better than any amp I ever heard. Lastly, AC/DC and Thunderstruck. I was a rockin! I listen to music when my emotion drives me, it takes away my pain from many surgeries, therefore I love acoustic guitar and movie instrumentals. I simply listened immersed in the sound. Was not missing my Class AB in any fashion. I put this down to the design of the Purifi and the Sonic Imagery buffers. The VTV is neither war nor sterile, I really think it gives you the intended sound. My system is decidedly budget in the audiophile world, but, I have a very high end budget system that plays beautiful music. I am happy, happy, happy.

  6. Tuckers

    I’ve had a lot of experience with digital amplifiers for almost 2 decades. I got the stereo Purifi with the Sparkos input buffer.

    Many can provide slam, dynamics, deep bass and clear treble. This one is special in that it sounds almost completely effortless, super transparent, with a wide and deep soundstage and the widest bandwidth I’ve heard. It does all of this while being completely free of grain or electronic artifacts and completely at ease and laid back. It’s the best digital amplifier I’ve heard, and among the best tube or solid state in my experience.

    Also, Warren is excellent at customer service and support. My unit was built and shipped in a day!

  7. Paul Champlin

    First of all, I am a customer and in no way related to VTV or Warren and this is simply a submission of my experience with him as a business owner and fellow audiophile.

    I purchased a pair of bridged Hypex (NC502MP) amps and a pair of Stereo (NC502MP) amps. The stereo amps power my JBL M2s and each bridged amp powers a JBL SUB18s in my home 2 channel system.

    Upon receiving the amps, I of course auditioned them. They shipping was superb and everything arrived as described. However, after listening for an extended period, I found the Hypex modules to be slightly less transparent than my previous Crown amps. So with Warren’s counseling and encouragement, I sent the Hypex Stereo units back for a swap to the Purifi (1ET400A) modules. Although the Hypex sounded great, I find the Purifi modules to be more transparent with better sound staging. But don’t get me wrong, the Hypex units sounded really good too but IMHO they weren’t as clean as the Crown Dci 4|1250n amps I replaced.

    I wanted to write this recommendation to share how enjoyable it is to work with Warren and not feel stuck with something until I was 100% satisfied. You have to search to find vendors these days that offer this type of post sales warranty but you need search no longer. Warren’s communication, his caring and his products are simply fantastic! I would gladly buy again!

  8. Erich Boleyn (verified owner)

    After receiving the Purifi-based VTV Stereo amp, my first impression was of the build, which is very clean with nice heft. Then after hooking it up and turning on the music, it lit up high-definition recordings exquisitely like I’ve only heard in very expensive amps before. Base – Midrange – Highs, all with authority and great detail.

  9. Charles Chan (verified owner)

    I have the VTV stereo Purifi in use for about a week now and would like to share my impression.

    Sound: very neutral like ‘a piece of straight wire with gain’
    open, transparent, fast, clean and clear
    nimble, agile and powerful with good rhythm and drive
    no sugar coating or artificial detail like some tube or SS amps
    in one word “MUSIC”
    Operation: no issues
    Built: beautiful 3/4 size chassis
    quality fit and finish
    stock Hypex input buffer
    XLR-RCA adaptor
    Value: super high
    hard press to find anything comparable at this price range
    Warren: business and custom relationship
    good communication
    very patient and responsive
    no hesitation to do business again
    Complaint: not really
    a short waiting time due to ‘out of stock’
    Future: trying the VTV/Sparkos or Sonic Imagery input buffer

  10. Peter (verified owner)

    I’ve now had the Purifi stereo amp for about a month. The amp it replaced was an Icepower 1200AS-based unit. I thought it would be an improvement, but I didn’t know it would be this much of an improvement! I should point out that I don’t have a lot of experience with Class A/B amplification, so I really can’t make any comparisons in that department. However, I’ve had several amps using Class D, and each one has been better than the last. This Purifi sounds so good, that I can’t imagine how anyone could argue that Class A/B is a better topology. The sound is significantly more full and smooth than that of the Icepower unit. I haven’t tried a Hypex amp.

    I called Warren to get more information on the various input buffers he offers, and he was very helpful. In the end, I opted for the Hypex factory input buffer and I’m very satisfied with that choice.

    My speakers are Tekton Impact Monitors and I’m using a Project Pre-Box S2 as a DAC/preamp. If you’re on the fence regarding Purifi, I recommend that you give it a try.

  11. Santosh

    After reading comments before mine, I was tempted to order Purify 1ET400A based amplifier. First I thought of buying a Stereo amplifier. But finally settled for monoblocks each with its own power supply. I requested Warren for few upgrades like Cardas binding posts and Neotech UP OCC copper cables for Connecting to Binding posts, and he was more than willing to accommodate all my requests. He was extremely cooperative and accepted all my requests even though the project got delayed a bit due to these changes.
    Finally the units were shipped to Bangkok, Thailand where I live.
    I was desperately looking forward to listen to these Amplifiers as I had read a lot on web pages. The packing was extremely good and safe and well protected.
    But to my bad luck one of the Amplifier failed as there was no music coming out even thought flint LED light was ON.
    I immediately contacted Warren. He response came without delay. He asked me to open the case and do a few check with Ohms/ Multimeter. After this he concluded that SMPS was working fine so the Purify module has failed.
    There were two options either to send the Amplifier back or get the new module and buffer shipped to me.
    As I live in the other corner of the world I decided to get the modules instead of sending amplifier back.
    This happened on Monday morning 9/21/2020.
    Warren shipped the new modules to me within an hour. I got them on 24th and my Amplifier was up and running within an hour of receiving the modules.
    As I got a chance to open the amplifier top cover, I was able to see the workmanship and layout of cables etc which was top class and solid.
    The initial impression was that these amplifiers are smooth sounding with wide and deep soundstage. I opted for Sparkos 2590. Looking forward to complete burn in to enjoy them fully.
    I would like to thank here Warren for his cooperation and top class customer care. We worked together like a team.
    There was nothing wrong with the amplifier and it was sheer bad luck that one of the Purify module failed which can always happen say one in thousand cases.
    I am a fully satisfied customer . Will look forward to buying again.

  12. Dennis Pinto (verified owner)

    I’ve had the Purifi ET400 amplifier for about two months now. Its strengths are in its zippy fast fast, catch-you-off-guard low-end dynamics and clean flowing smooth highs. It my ears, power delivered linear and will play north of 100 dB without a sweat. It runs cool and in my system has no noise floor at max. gain. Its personality, is no personality, It does what you ask, and is happy doing it all day.

    I purchased my unity with the Sonic Imagery 990, but I’ve never heard any other opp. amp so I really can’t comment on its sonic signature other than it sounds great in my setups.

    If you saddle this amplifier some sort of tubification, your speakers will take on a more analogue breath in both tone and timbre.

    I’ve been waiting and testing Class D for a loooong time and finally believe that its arrived. Thank you BRUNO!

    VTV’s customer service is fast and responsive. I asked several questions (some NOOBish) over the course of a year or so and they were patient, never selling me.

    I ordered the unit on a Sunday morning and I was listening to it from Raleigh, NC on Wednesday afternoon. Smiling my ass off 😉

  13. Dan (verified owner)

    I purchased the VTV stereo Purifi amp to replace older Anaview modules used in my recording studio with Amphion speakers. I went with VTV because I heard good things about customer service and it turned out to be a good choice. Warren was very flexible about returns and trying different op amps and he didn’t charge extra to replace the internal cabling with my favorite Furutech that I sent to him.

    I tried all three op amps, and my experience is that they all require 25-50 hours break-in, so be prepared to run pink noise on them. You cannot understand them with a few hours listening per day for a week. They change their characteristics by becoming more mellow sounding but also more deep around 36 hours. My favorite is the Weiss, which has stunning accuracy and a powerful, musical sound. They come from the $25k Medeus DAC and are a steal at this price. I upgraded my studio cables to the Furutech DSS to be able to handle it. The middle of the road was the Sonic Labs. A good all around choice, very detailed still, but a bit dry. The Sparko is the least detailed, but has a relaxed sound for people on lesser cables or want a relaxing hi-fi experience.

    I also went with Furutech pure copper binding posts over the WBT, but I heard both. Again, these take around 200 hrs to break in, like all Furutech/WBT products. The WBT are tubey, sweet and euphonic, and the Furutech are less sweet, but more accurate. The great thing about this amp is the transparency – you can really hear what changes in the signal path do like never before.

    My only complaints are that the chassis puts the XLR under the posts, making a hard time for spade users. It would be nice to find a better chassis, maybe even one more compact as well, but its not a deal breaker. Thanks for the great amp. I highly recommend it!

  14. Bill Bailey (verified owner)

    Astonishing resolution, transparency, instrument separation, and ‘air’ are what you get with the Purifi amp. Likewise amazing large- and small-scale dynamics and powerful, articulate bass. I also hear more accurate instrument timbres than ever before; that includes cymbals and other percussion instruments.

    I have have had both the Hypex buffers and the VTV buffers with Sparkos SS3602 op amps. I don’t recommend the former: I heard some weird distortion during load passages with high-range instruments like brass, strings, and woodwinds. I took the VTV’s with Sparkos to remedy this. Accordingly I recommend only the latter, (or maybe the Purifi Eval but I haven’t heard myself).

    However there is some downsides to the Purifi. If you like a “warm”, “organic” sound, forget the Purifi. Also the Purif is highly intolerant of overly-bright or otherwise not-so-great-sounding recordings. If you use a nice tube preamp it may mitigate these negative to a significant respect.

    So in conclusion the Purifi offers SOTA sound in several major respects but it isn’t necessarily for everyone.

  15. agim perolli (verified owner)

    not just an excellent class-D amplifier, but an excellent amplifier – period! in my system, which my large magneplanar ribbons that extend up to 40,000Hz, i needed to try a few different input buffer options until i found the one that i felt was entirely transparent. for me it was the weiss input buffer option that elevated the performance to the top tier. the amp it replaced was a very mature class-AB design from Classe electronics. warren was patient and helpful, working with me until i found the winning combination. i think anyone would be hard pressed to find anything not to like about this amp, as it sounds clear, smooth, easy, relaxed and liquid in presentation. in my setup it is not intolerant of any recording — it neither accentuates bad recordings nor sweetens them. it does what an amplifier is supposed to do: amplify the signal without changing anything but it’s amplitude. seriously, to my ears (and i listened damn closely, as warren can attest, going back and forth between amps and with different speakers), this is simply a great amp that sounds like it should. my high resolution digital files and vinyl LPs sound sweet, natural and organic.

    since i had to open up the amp to try out the array of input buffers warren sent me, i had plenty of time to look inside the chassis. it is a clean, sparse internal layout that is obviously high quality engineering work. i also set the gain jumper while in there to the higher gain setting.

    one thing i did learn, which i didn’t appreciate at the outset, was how much a difference the input buffer makes. one option sounded bad to me, exactly the sort of sound class-D detractors describe. another sounded too rounded and lacked transparecny. another was pretty good and hard to fault. and the one i ended up with, i would challenge anyone to listen and tell me the difference between this and a class-A amplifier.

  16. Wheat (verified owner)

    I’ve been auditioning my VTV Purifi Amp (with Hypex stock buffer) for maybe 6 months or so by now. Its an smaller office setup paired with an RME ADI-2 DAC and Magnepan LRS speakers. Its a handsome, well built, basic black unit.

    I’m not into all the audio poetry so I’ll spare anyone who reads this all that and come at it with a practical angle. Put simply – this amp is an incredible value in high end amplification. At the time I’m writing this, Warren sells this thing cheaper than I can source the components and do it myself. If you have the need, I’m confident one of Warren’s units will absolutely meet and likely exceed your expectations.

    I’ve resisted the urge to experiment with the various buffer implementations because I wanted to live with the standard offering for a while first. At this time I don’t feel one is “settling” with the standard configuration. That said, it is a fantastic option that Warren will work with you to tune your amp to your preferred sonic presentation with the various buffer options. I bet the tube buffer would be fun to compare.

    Buy with confidence and expect not only one of the best values but also one of the best examples of high end amplification available with today’s technology.

  17. Dan2 (verified owner)

    I received my VTV Purifi stereo power amps here in Malaysia yesterday. The package went from Ohio to Louisville KY, to Anchorage Alaska, to Incheon South Korea, to Shenzhen China, and to Ho Chi Minh Vietnam, before arriving here in Malaysia 7 days after being shipped from Ohio.

    Everything is working fine. I opened up both cases before powering them up, just in case they were accidentally left at the 120V setting (they weren’t).
    The build and assembly quality is excellent.

    I ordered the standard binding posts and the VTV Buffer option with Sparkos discrete op amps.

    The standard binding posts are not spaced for the standard banana plugs, but they have large holes for the insertion of thick, high quality cables. Once tightened, I think that the connections would have lower resistance than when using banana plugs. This keeps the damping factor high.

    My speakers are a pair of custom designed (by me) 6 foot tall line sources with an array of 12 mid/woofer drivers next to a custom built tall ribbon line source in each. They are heavily acoustically damped and use a phase coherent electronic crossover that allows them to accurately reproduce square waves.

    The sound is better with the VTV Purifi amps. The transients seem better, and I notice more ‘heft’ in the lower mids. To my ears, it wasn’t a day and night difference from my old ‘professional sound reinforcement’ power amps, but the difference is indeed noticeable and indeed an improvement.

    Technically speaking, my guess is that the majority of the differences are probably due the the extremely high damping factor of the Purifi amps over the whole audio range. They simply control the speakers and ‘make them behave’ better.

    As an engineer, I’m a fan of AB comparisons. Ideally, it would have been ideal to reasonably rapidly switch back and forth between the old and new amps several times while carefully listening for the differences.

    But given the wiring and connector differences, easily and quickly switching back and forth between the old amps and the new VTV/Purifi amps was not practical.

    So for now, I’m content to conclude that they do indeed sound better and leave them in place.

    An additional positive difference is that my old power amps had fans which were somewhat audible. The VTV Purifi amps are completely quiet.

    I wasn’t absolutely convinced that the VTV Buffer option with Sparkos discrete op amps is audibly superior. But the VTV Buffer option allows experimenting with different op amps in place of the Sparkos ones. I plan to experiment with this in the future.

    But for now, I’m content to go through my sound library, including some recordings I’ve made myself, and enjoy the music.

    All in all, a great purchase from VTV!

  18. Alex (verified owner)

    The amp arrived yesterday (stock Hypex buffers) and I am just thrilled with how it sounds. It drives my JBL Studio 590’s to unreal levels without any negative artifacts. Best amp I’ve ever heard with these speakers.
    Very pleased with your product. Thank you!

  19. Bryan (verified owner)

    Picked up the VTV Purifi with Sparkos pro for a 2nd system to pair with a Matrix Audio Element M2 and I really like what I am hearing.

    Received my amp in 5 days from order. Chassis is classic, modern and clean. Sounds really nice with solid bass control and natural midrange, treble. Soundstage from the combo is very large and deep.

  20. John Nosewicz

    It is a stunner! Very affordable and beyond this the megabuck amps seem like mere dressing-up. I got the standard Hypex buffer; I’m not looking to “tweak” the sound so I got my straight wire with gain. Advice: if you use 5mm bananas get pure copper ones (at both ends; think hysteresis) Or use the plastic shell (hysteresis again) speakon connectors; both Neutrik and Amphenol make nice ones.

  21. Mark D.

    Excellent Customer Service! My Hypex NC502 amplifier developed a problem within the module. One of the components was defective. I contacted Warren Coleman and he gave me instructions for sending the amplifier back for warranty service.

    The turnaround time was lightning fast, within one week. A new module was installed and the amplifier was bench tested and passed every test. The test page was included inside the box. Having it back in my system within a week from California to Ohio and back is nothing short of a miracle.

    I have been in this hobby for as long as I can remember 40+ years now and I have run the gamut on audio gear from Class A Krell to BAT and ARC gears, both tube and solid state. I listen to records mainly and I own power hungry Magnepans. I’ve tried all the major brands and have loved many. But I have never been more engaged, more drawn to want to listen and constantly blown away by what this amplifier does with my all tube balanced front end for my music than any amplifier before it. I have never been more satisfied. That says a lot considering the massive amounts that have been spent over the years.

    When I discovered Class D tech it was after going down the battery operated tripath road. I’ve literally done it all. I’ve had Ice Power, Class-D Audio’s Two channel balanced designs and their new Gallium Nitrade (Mini Gan5). To my ears the amp I chose, the VTV Hypex N-Core NC-502 beats them all. Although there are now much higher end and multi channel designs with various other buffer options offered by VTV, I have no desire to explore them. When was the last time you felt that way? For me it was once or twice over many years. But now it’s an everyday occurrence.

    If your curiosity is piqued and you’ve been wanting to try one of these, you should pull the trigger and experience the magic for yourself. These are without a doubt the best bang for your buck in all of Audio.

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