Most talked about Purifi Class D DIY amplifier. Discussion / review

#audiophile #hifi #highfidelity
Patreon account: / thomasandstereo
Non-affiliated links:
Purifi class D kit: purifi-audio.c...
Neurochrome aftermarket input buffer: neurochrome.co...
Ncore SMSP power supply: www.hypex.nl/p...
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Gear used in this review
Quad 2905 speakers
Spendor D9.2 speakers
Silverline Sonata speakers
Focal 1008 BE speakers
Focal Sopra 2 speakers
Exasound E28 DAC
Doge 7 Tube DAC
Doge 8 Tube Preamp
Schiit Freya tube preamp
Audio Research LS25 preamp
Matrix Mini Pro DAC
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Track: Left Alone - Airixis [Audio Library Release]
Music provided by Audio Library Plus
Watch: • Left Alone - Airixis |... ​
Free Download / Stream: alplus.io/left...
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Artist: Patrick Patrikios | Track: Voices

[@ThomasAndStereo]

Another reason I decided to put my project on hold is that I am waiting for a better power supply solution. As I said, my $4k class D amp feels more powerful and I think it is the power supply because Mr. Vintage amp that uses an NCORE module (I believe they are related to Purifi) feels more powerful. In that sense, this amp does not beat my higher-priced amps. Btw, For those of you who have not seen my latest AUNE S8 video. kzbin.info/www/bejne/pV6zeI1vnK6iobs I found this good tutorial on how to build it with the kit input buffer board. Once you use the Neurochrome board, it will no longer fit the casing. kzbin.info/www/bejne/o37QnH5un86mesk

[@xxgamerxxchrischris2325]

hey thomas whats up dude i was wondering what do you think is the best sounding dac that you ever heard

[@ThomasAndStereo]

@@xxgamerxxchrischris2325 This one. kzbin.info/www/bejne/r6TVgGCFnZmVi8k

[@xxgamerxxchrischris2325]

@@ThomasAndStereo daang ohh woow this one is actually super super cool and the sound quality sounds amazing!

[@xxgamerxxchrischris2325]

@@ThomasAndStereo I think that other dacs sound really really good as well I mean the smsl su9 smsl 400m?

[@ThomasAndStereo]

@@xxgamerxxchrischris2325 Yeah, most DACs today are good enough. It is crazy.

[@dominicvalois]

Hi Thomas, you're 100% right, Class D has come a long way from what it was just a few years ago. I would totally consider a Purifi amplifier, I'm actually testing one at the moment and it is quite impressive.

[@ThomasAndStereo]

Thanks for sharing!

[@jaimegarch]

I think you have just elevated yourself past other reviewers. The moment you start thinking "hmmm....I wonder if I can do this better..." and start making your own gear you get a deeper understanding of the gear and what makes it sound the way it does. Congrats and looking forward to your hot rod builds.

[@joshdekubber3631]

Very cool project Thomas! I wish I had the opportunity to try out multiple amps on my speakers. All I can do is as much research as possible and make an educated decision but learning from your knowledge and experience is a big help!

[@kinsoncooper7333]

This right here is why I support your channel... you're an audiophile with a soul.. keep breaking those barriers. Audio is for everyone.

[@albertloan396]

Was glad to hear a reference to NAD which I find oddly ignored in much of these discussions.

[@Grizzly1644]

Interesting timing with this video. I am trialling an NAD c298 Purifi amplifier currently. Comparing it directly to my Firstwatt F7 class A, the NAD sounds excellent. No harshness, driver grip is excellent and the presentation is always smooth. I will say the decay tails on the Frist Watt and the First Watt's ability to create Holographic soundstage can't be matched by the NAD c298........But the NAD c298 is far more dynamic, displays much better grip, and transients are fast and agile. I will potentially grab 3x NAD c298 for an active speaker setup, using the Okto Reserach Dac 8 Pro as the front end. I will say the Purifi although it ticks alot of boxes, does fall short in micro detail, decay, and instruments space/staging V's a good class A amplifier. But the Purifi does paint a full wide, and fleshed out soundstage. Choose you flavour I guess.

[@decoryder]

Thanks for the insight Thomas. Yes, I find that the combination of a good class d amp, and a flexible tube pre-amp make for the ideal combination. Most good class d amps will simply reproduce the upstream signal without added distortion or colorization; in combination with a tube pre-amp it's really just a matter of taste in terms of tube rolling as to how to 'flavor' the sound going downstream from the pre-amp - there are many options, and the class d/tube combo is far more linear and predictable than going class a or a/b in the same configuration.

[@SpaghettiKillah]

Which is why a tube pre-amp coupled with an active speaker is such a killer combo! You can tube roll to adjust it to your taste.

[@decoryder]

@@SpaghettiKillah Yes, good point - the latest generation of class d really brings active speakers to a whole new level, and they will only gain in popularity!

[@yttean98]

I use bi-amping via an external DSP, driving a two-way speaker, a full range and a bass driver, I drive the full ranger with an 18Watter Chipamp and Class-D driving the bass driver. Sounds good and as well as cheap too.

[@yttean98]

I forget to add, this way I can TUNE the sound to my likings ie to my heart's content, then after a while, when I tired of the sound I can change using a few keystrokes and a microphone. All I can also change the drivers(ie using different materials, eg Kelvar, carbon fibre etc) if I wanted to. Dirt cheap, time-saving and effective, and many more adv.

[@sebastiaanhoenderdos7458]

@@yttean98 I'd like to know more about your setup, sounds like it'd be my cup of tea.

[@yttean98]

@@sebastiaanhoenderdos7458 Good sound nowadays is within the reach of everyday audio enthusiasts. At the same time learn and enjoy music as you go, no need to spend big bucks. BTW I have many years of audio experience and I can afford expensive equipment but I prefer to DIY. This is just a hobby now, DIY you can configure and tune the system to your liking and change whatever and whenever you prefer now then at later date, then you have a "NEW" system. Results: Cheap and flexible.

[@yttean98]

@@sebastiaanhoenderdos7458 More importantly it is fun if you like to consider it this way. For me it saves me money. This way you channel your money elsewhere where they needed most, like your child education.

[@sebastiaanhoenderdos7458]

@@yttean98 sounds good to me, may I ask you about what you're setup is? In terms of amps and speakers. I'm fairly new to the audio DIY route.

[@neps4th]

I have been Bi and Tri amping my systems since '78. Starting with Magnaplanar Tympany and Infinity Servo-stats; Substituting Electrostatic tweeters onto Tympany mid-bass panels. I used an active crossover to audition many different amplifier combinations. Both tube and ss combinations. Life has never been the same ! I demonstrated such a system at CES around '85. A famous Magazine Reviewer commented: "Most convincing illusion of reality I ever heard" !

[@ronaldmcdonald2456]

Thomas, thanks my friend for once again brightening my day! As a committed DIYer (or, maybe that should be "a DIYer who should be committed" :D)---I'm always happy to see the kinds of undertakings you've highlighted with this one. It's becoming easier as certain prices come into line with reality, and more of the pieces become plug-n-play. Also happy to see Tom Christiansen getting his props. A scholar and a gentleman who mentored me though several of his Neurochrome amp projects. Finally, an addiction that doesn't rot my brain.

[@jonsays3762]

Sounds neat, in a growing up watching my dad with a soldering iron sort of way. I spent a grand on wharfedales and decided to spend the rest of my music listening budget on a bass boat. And a pickup. You gotta do you.

[@mtiken]

Good idea Thomas. 1. Get a good class AB amp with a pre out 2. Get a good active subwoofer with Class D and hook up with the pre out 3. Tune the subwoofer for the crossover. The issue could be latency and timing :-(

[@RoyFJ65]

Its your review of SMSL amplifiers that got me interested in class D amps and I purchased the SA400 based on your VMV A2 test. After six months no regrets playing it back on my NS1000 speakers. Surprised to see how well it sounds compared to my other amps from Yamaha and Accuphase.

[@tccincrj2866]

Mas, keep these discussions frequently, please! This was awesome! Thanks, man!!

[@alexkerrison411]

Nice project Thomas and thanks for sharing! Enjoying my 300watt Icepower Class D DIY amp with Emotiva T2+'s. Nice clean tight bass. Think I will try a Hypex or Purifi with that buffer board next.

[@jazzmetalaudiophile]

Thank you for the update on that very interesting project. Now I am really curious how it would sound with a big chunky power transformer and tube buffer stage. Pls keep us updated Thomas

[@ranbymonkeys2384]

Even with 12AX7's make a hell of a difference and those aren't that big.

[@michaellee6654]

The buffer from Neurochrome was a nice discovery. Neurochrome is for the serious DIYer who understand the limitations of some aspects of DIYing but Neurochrome fixes those aspects All his products are serious performing gear.

[@owendavis5024]

Any idea where to get a case that fits Neurochrome?

[@michaellee6654]

@@owendavis5024 if you have drill press or can drill, try aliexpress and search amplifier case.

[@marcdostie8409]

I got a Purifi Amp from March Audio and love it!

[@TonyBologna999]

Did you consider any other vendors? Where’s the March Audio web page? I’m looking at VTV and Apollon as well.

[@geoffreyhowlett2672]

I'm also thinking of the March Audio Purifi stereo Power amplifier. I live in Australia and they're an Australian company. I believe the amp is approx . $AU $2000. It has a Hypex power supply

[@TH-lo8mq]

@@TonyBologna999 Apollon and March seem to be the go-to for the Purifi right now. The build quality looks very comparable. I have the Apollon Mini. It's nice having the RCA option and adjustable gain. VTV may be a better value, but they have a bit lower build quality and attention to detail.

[@Tony-tk4ng]

I bought a March Audio P452 Purifi amp about a year ago. It is very transparent and it will amplify nice sounding music if the source+DAC+preamp are good. Any weak link in this chain shows up with this amp. March Audio makes its own buffer board. It beats a number of power amps that cost up to A$10K. Alan March is a nice guy to deal with.

[@milosdunjic8718]

I got Buckeye version of the same … love it as well !

[@mrpmj00]

I love my NAD c298 (similar to NAD M23) even more than my already great Parasound 2125v2 amp. Apple Music lossless

[@denteomd]

Thomas, I built my Purifi amp around October last year, used the same casing and power supply from hypex. In my experience, the sound changes with different pre amps. I'm already pretty happy with the Topping A90 and Chord Qutest DAC with it. connecting it via XLR which adds more gain. Planning to pair it Decware tube pre amp, but that will take sometime though as the price is a bit high. Don't want to anger the wife (boss). I haven't tried Neurochrome but I think I would have problems with the chassis holes and have to do soldering if plan to change the buffers. The Purifi is really a great power amp considering it is class D and delivering lots of power. It's a very easy build for those who plan to do it. It just took me less than hour to assemble it.

[@Lutznn]

Tomas, I love your project! I tried something similar last summer when I coughs the DIY bug. My goal wast to combine a Glassware Aikido tube preamp with an Ice Power module. I’m sad to say it’s still half finished but perhaps seeing your videos will motivate me to finish it. Nice improvement on the room! Enjoy

[@BootJamesOut]

Wow I'm shock to see so many more folks that's into DIY, hello and welcome. Thomas your a good role model as I'm a Niillionaire this topic is right on. if I can not make or build it or improve on it, then i do not want it, type here. The old school bus driver I is. Just how do you find the time to do your thing Thomas and have a nap. Your always smiling and excited I just hope that you don't wet the floor like a puppy does. As this topic I sure wet myself. Yep I'm still crazy. Folks never stop enjoying life, let the good times roll remember its good to be bad the good way. Ride Easy

[@blathum9]

I love you usage of the word sweet very well defined thanks Thomas.

[@richardhing1418]

Thank you for the insightful review of the Purifi Eigentakt 1ET400A Class D amplifier. I have a Pass DIY Aleph J Class A amp and a rebuilt McIntosh MC240 tube amp. While they both are excellent sounding amplifiers, I want to build a more energy-efficient amp that runs cool for the warmer weather months. I've dabbled with Class D amps and my latest is a Texas Instruments TPA3251 PurePath-based Class D amp, but like you, I want a reference-level quality sound, so watching your review where you have evaluated the Purifi Eigentakt Class D amp module with the Purifi FE02 input buffer module along with the Neurochrome input buffers was illuminating. I admire Tom Christenson's engineering designs for DIYers including his Modulus-86 Class A/B LM3886 chip amps, so when you stated that the Neurochrome input buffer elevated the Eigentakt's performance, that grabbed my attention. I guess I would need to build a custom enclosure to properly house everything, but this gives me some flexibility in trying out power supply designs as well.

[@fonkenful]

Late to the party on this one, but I’m another big fan of Tom’s work. I’ve been running one of the original small batch of Modulus 286 kits for several years now in my living room system and quite love it; his 686 is a beast, but excessive to that particular use case. Also using two different models,of class D in my Atmos 7.2.4 system, and while if budget wasn’t an impediment, I’d go Modulus throughout, the appeal of class D’s efficiency and relative affordability is hard to ignore. Additionally, I’m of the opinion that any minor deficiency or sonic signature of the power amp stages in a home theatre system are overwhelming swamped by the audio mixing of the soundtracks; and then there’s the numerous options for DSP correction of speaker response, room correction, etc.

[@tallpaull9367]

Is why Billie Amp and Rogue Sphinx do what they do. Bet that NAD M33 is really good

[@wric01]

Good future video would be purifi Vs new GAN amps like Starkrimson, since price is about same range 1-2k.

[@seandavis6392]

I've been itching for a review of the new LSA Voyager GaN 350. I'd love to hear Thomas's take and how it compares to the Purifi. I actually wrote Underwood HiFi and asked if they'd send a demo model to Thomas for review. They wrote back and said it might be possible at some point, but they're super back ordered right now.

[@shawno1586]

Allow me to add the Premium-Audio Mini GaN 5 Gallium Nitride Amplifier. $749. I love it

[@tcc5750]

4:06 Nice class d has come a long way

[@scarrattRS]

Brilliant great video 👍 more like that please looking forward to more of your projects😊 Ross. Somerset England

[@ThomasAndStereo]

Thank you! Will do!

[@LuxAudio389]

Great that you have the support from Doge and Mr. Amp. I'm sure you'll find a better power supply. There's a lot of smart and great people on your channel🤓

[@brs2c]

What/who is Mr. Amplifier? Would you mind posting a link?

[@LuxAudio389]

@@brs2cMr. Amplifier is someone Thomas mentions in this video at 7:07. He designed and built his own amplifier.

[@samuellord8576]

Thomas, please mention that the input buffers provide nearly _half_ of the gain for the amp! The current Purifi module has only ~12dB of voltage gain. Of course current gain is its main job, which it does superbly. This is one reason the modules measure so well: they are not as great an improvement over nCore as the measurements suggest. However, putting more gain in the input stages is indeed the simplest way to improve overall performance. This is superior gainstaging by design.

[@epi2045]

Now this is a guy who’s thinking. Thomas great video!

[@tomkoz2812]

Hi Thomas. I did that idea over 20 years ago. Small tube monoblock amps plus 2 solid states (AB). Passive x-over before those amps. SS 9500 and 8" kevlar. Definitely good direction. Thanks for your work from Poland Tom. PS if you are interested in new patent pending speaker technology let me know.

[@ThomasAndStereo]

SURE! Email me at [e-mail]

[@vortextubes]

Still waiting for your VTV Purifi Amplifier review, Thomas 😅😁

[@tek00732882]

Excellent video, more of this type of chatting pls....

[@netnakul]

Tube pre --> Purifi amp is something I've been pondering for a while. Would be great of you can compare various tube preamps when used with this DIY amp (other than the Doge)

[@FatalethaL]

In my experience thus far, having a tube pre with a class D (i am familiar with the 1200AS2 module) is a quick, easy and affordable way to get great sound. Class D has came a long way and it's fantastic in my books. In this configuration, the tube pre becomes the "soul" of the music and system. However, I have met some people and they are hesitant to approach their system configuration in this way (possibly because of "infamous" class D sound and performance). I guess some audiophiles never liked the quick, easy and/or affordable way. On a serious note - There is a challenge to fully unleash the tube pre/class d power amp configuration because class D (in general) are true balance by design, while many great tube preamps are single ended by design.

[@Biefstukje]

@@FatalethaL schiit Freya seems like a good match

[@Shaken_AND_Stirred]

Those Focal monitors are beautiful.

[@chrisboylan4599]

I am trying to integrate my Willsenton R8 with class AB monoblocks. I also have that ice amp and find a pair of Vidars run in balanced mode crushes class D. I am thinking of getting the Emotiva XPA-2 Gen 3 $1100 class AB vs the Vidars all in balanced config. Especially since I get 20% Emotiva bucks for use on next purchase as a black holiday promotion. PS: I just bought the Starke AD4.320 class AB amp instead for $1100 with a $300 discount around a Black Friday sale. Especially since the Emotiva sale is good till the end of December!

[@robk5745]

This so cool, I will be trying the tube pre amp with this purifi for sure! And I love the focal 1008be, so this would be like my end game set up.

[@ThomasAndStereo]

Yup, just keep in mind Class D has a linear bass. I personally would wait for a company to come up with a better power supply with for it. The class D module is fine but I wish it has more power.

[@robk5745]

@@ThomasAndStereo good point! Next on the list is el34 amp for my rp600m, so I have time to wait for updates. Nad c298 is of interest too.

[@samuellord8576]

@@ThomasAndStereo Why not go dual mono? Use 2 SMPS instead of one? Much more expensive, but there is every reason to do it.

[@critic86]

Thomas, for that Doge + Class D project you will need class D amp with the same gain. You can get much better results (and a lot easier!) with just tube amp + easy to drive speakers and add 1 or 2 Rythmik servo subwoofers. They use Hypex class D amps and they have settings to fine tune the subs with speakers.

[@chris292]

I WAS REALLY REALLY THINKING DEEPLY AND WONDERING YOU KNOW ABOUT DACS AND SUCH WHICH DAC SHOULD I GET??!!!!

[@Chapterrifik]

Awesome stuff Thomas 🤜💥🤛

[@ThomasAndStereo]

Glad you enjoyed it

[@Chapterrifik]

@@ThomasAndStereo always interesting and different. Really appreciate all these talk about class D amplifiers especially when I still have my Elac Uni-Fi UB5 and looking for an extra detail on the top end seems to me it's a good option without emptying out the Bank

[@jamesrobinson9176]

I've been doing this for years. I use a fisher tube amp from 1962 with a pair of goldenears. Sounds good ☺☺☺👍👍👍

[@ThomasAndStereo]

Very cool!

[@PGHJR002]

Sound is VERY smooth, not the least bit edgy or SS sounding at all.

[@gw61]

I preordered the orchard audio starkrimson ultra with GaN modules. I’ve never heard it in person. I wonder how it compares with your amplifier. All the KZbinrs I’ve watched have said the GaN amplifiers sound the most real and live. And the purifi amplifiers sound the most neutral. The excitement with the GaN was from enjoying the listening experience. The excitement with the purifi was around the idea of knowing what neutral sounds like.

[@daniellustgarten5857]

Hi !!! i already did ti ,I use a Cayin MT34 MkII+SMSL DR-9 , the cayin its connected to LS3/5 Rogers speakers and the SMSL is connected to a 10'' subwoofer ,from a SMSL M400 DAc , the result is really funny and enterteining

[@alvingovindan6339]

Just ordered a purifi kit... now the wait!!! Any recommendations on a preamp Thomas? I was almost set on a schiit freya plus but I see you say it’s just ok? My google research took me shortlisting the topping pre90 and the freya. I would probably wait to get the amp built and see how it sounds with my Cambridge Cxn. I need the preamp for my vinyl tho. I also looked at building a preamp using the universal buffer from Tom at neurochrome. Any recommendations or insight will be appreciated.

[@ThomasAndStereo]

Omg! Hey, I am about to review the VTV class D amp using the same module but with a tube buffer for not much more, perhaps that could be another solution. If you can put a pause on your order, you might want to wait for my review because that one is completely build and you get a warranty with. If you cannot, its fine too. Preamp with Freya is ok, just no audio research. kzbin.info/door/MVtSHXafOEcFN10FYygDTAcommunity?lb=UgygCZ52J083oM6_fYF4AaABCQ

[@BoBSmith-sz4dc]

Hi Thomas, you might want to try to bypass the buffer completely using the eval (purifi buffer) by changing the pins, it removes all the limitations any buffer adds, have way less gain but sound better in every way, for me the gain is still enough for my speakers.

[@ThomasAndStereo]

Yup I prefer it without the gain too.

[@andrea585ny]

Hi Bob, what pre do you use with the Eval 1?

[@TimBedford]

Hi Bob, I have a Purifi Eval1 with the Purifi buffer board. What do I need to do the bypass the buffer or reduce gain? Is anything needed as well as changing the jumpers? Is this risky in any way? Thanks Tim (Oxford UK)

[@nc3419]

I always thought a sweet high end was soft, non-aggressive but with a pillowy, extended frequency range with slower decay.

[@ThomasAndStereo]

That works, great way to explain it.

[@robk5745]

Sounds like something I want!

[@hoygising1]

Hey mr Thomas what is your reference song or songs when u review a let say speakers? Thanks

[@ThomasAndStereo]

They are Chinese songs but these days, I just listen to music instead of using a playlist. If I did not do that, I would not be able to enjoy anything.

[@normally624]

I run my Purifi with the PS Audio BHK pre with NOS valves and it’s certainly improves the sound . I think if you can find one a tube preamp with tone controls and balanced outputs it would be handy . Not asking for much .

[@PGHJR002]

Congats on creating a hybrid with the DOGE 7 and Purifi class D, cool.

[@dayalanmoodley2819]

Thank you for the informative video

[@francisdelacruz6439]

Nice Review impression of a DiY projects.

[@bikall1]

Thomas, better use REW and measure the audio output for comparison. I measure an edge XTZ 300 W class D against an hegel H95 95W class A. In pure spl the hegel wins hands down. But it also shows the lack of bass output on the xtz. The difference was at max 6 DB in the lows. People telling the hegel sounds "warm" then this is your answer. In the rest of the spl curve the differences where almost none. I can't imagine someone could hear that.

[@sc51153826]

Excellent idea, but before building one amp with both types inside. Have you already experimented with mixing class D and tube amps to bi-amp as separates? Does it work as well as you expected on a few difficult-to-drive "bi-amp'able" speakers? IMHO, The sonic properties and power difference between the tube and the Class D seem like a large gap to me. Actually, it would be so exciting and more interesting if you make a video on bi-amping with 2 identical vs your hybrid method? Thank you for your hard work!

[@sc51153826]

I guess he has and, maybe there's a bit of his "magic sauce" that we just have to wait and see😊😱🤞

[@sudd3660]

purifi sure is an interesting product, i folow all class d amps. recently got myself purifi in the nad classic 298, it is a bit large and runs a bit too hot for me under low loads and idle. dont think chassis size will help to keep things cool either, no heatsinks. maybe it is for spacing and electromagnetics.

[@ThomasAndStereo]

Yeah Purifi told me it is best to design a heatsink to go with it.

[@budgetaudiophilelife-long5461]

😎 ENJOY YOUR JOURNEY …HELP OTHERS…. A WIN / WIN 🤗🤗🤗😍😍😍

[@chrisvinicombe9947]

Couple of suggestions. These modules don't need a buffer if you have a preamp that can push 12V. The hypex power supply is good but running two of these modules is asking it to dig deep. Better to go dual mono front to back for dynamic headroom.

[@ThomasAndStereo]

Yeah, I wanted to try the Mono version too. Something to consider in the future.

[@soowat1190]

Love Class D with tube.

[@grandpa4316]

I used China made Class AB solid-state amplifier circuits to make my 5.1 amplifier. The sound quality is very good. At first I tried using Class D amplifier but they sound terrible.

[@CinemaDemocratica]

The Dared DV-6C is an integrated amp with a tube-buffer preamp and a class D amp stage -- and it's about $400.

[@ThomasAndStereo]

Darn, so affordable.

[@CinemaDemocratica]

@@ThomasAndStereo I had one for years and I liked its sound very much -- I can only imagine what it would sound like with SOTA op-amps from T/I.

[@MrPkimura]

Great video, Thomas. Small typo at the end in the sound demo. I think the pre from Doge is the 8.

[@ThomasAndStereo]

Thanks for the correction!

[@ramsaybolton9099]

Great idea. Tried bi amping with my Yaqin 100b/ Mac Mc501 and the volume levels didn’t come out right. What would be nice is an easy to use crossover where we could plug in our tube amp and ss amp and voila, Bi amp.

[@jmgoodmanuk]

Am I bi-amping as I am running a Node 2i to 2 monoblock amps (for L & R) with a seperate subwoofer preout from the Node directly to my sub with built in amp? Never thought about it before... I use a pair of bookshelf speakers (JBL Studio 530)... Nothing wrong as a 2 channel system but 2.1 is a bit more meaty with added depth.

[@hoobsgroove]

your best bet for a tube amplifiers to drive it with a class D amplifier as it's power supply 4000 + Watts would ideal

[@saedamad]

Good idea....

[@fearwolfbrewery5014]

In the video it looks you did not only change the input buffer boards but also one more thing? The thing the chord from the powersupply goes to?

[@jeffkalina7727]

Interesting find on the Focal comparison. Class D misses on the bass I am told. In time they should correct this.

[@cameronkrause4712]

very interesting video- thanks Thomas! But, that song oh no!

[@ThomasAndStereo]

Ah, it is copyright free music so that is why I use it.

[@cameronkrause4712]

anyways, I think this was one of the best videos relating to class-d that I have seen- I like your openminded approach.

[@GabenB]

Have you ever handled the Micca RB42's? Just wondering what is an affordable amp option that would pair nicely. I purchased the SMSL AD18 and felt it was terrible quality.

[@MegaPete]

Awesome idea Thomas jut wonder eh

[@lukaszx5271]

Hi Thomas.Thank You for another amazing video. Original subject , probably never been pointed out before. P.s.One of the amplifier in collection of your is Pathos logos. I become the owner of this fantastic amplifier. I am using opera seconda MK2 speakers. It sounds very nice but I am thinking logos would need something more revealing and transparent. What speakers would You recommend me to get the best match?big thx Lukas.

[@larrywe3320]

Cheap audio enthusiasts , like me , have been using Tube Preamps with Class D/Chip amps for years. But maybe not at the level Thomas wants to achieve

[@akia123]

I'm glad to jump into that world

[@yeanxiang]

Hi Thomas, do share with us if you have tried Hegel P30 preamp with this Purifi Class D amp and how's the result compare to tube preamp. Thanks

[@ericperry72]

And just like that I'm about to spend more 💰 😆. Also, sounds like the search for a bigger power supply board is underway.

[@MrMftech]

The secret of the pudding is the -input buffer- !

[@nilswijgers3849]

Don't know if it is suggested yet. But how about a review of the ATM- Audio class d amps with a KORG Nutube input buffer.

[@Chuek-WaiTai]

Purifi's performance reaches high end level but not the look. Its performance and characteristics can be tuned by the buffer board. If people do not like op amp, they do not like it. Nice review. Thanks.

[@zelareka]

Thomas, what if you use a good preamp like p20 or p30 and bypass the gain stage altogether?

[@anjovandijk9797]

Would be nice to hear your opinion about the not so expensive NAD C 298 class D Amplifier

[@ThomasAndStereo]

I would love to also check them out.

[@anjovandijk9797]

@@ThomasAndStereo and earned the product of the year 2021/2022 eisa award ⭐

[@mzmz9355]

Hi Thomas & good that you are pioneer for searching the best sound combining known approaches. BTW: When evaluating your concepts , do you also measure the results?

[@ThomasAndStereo]

No cause I don't have the equipment.

[@AhmedAddas]

Thomas did hear yamaha px8 amp? Also i agree with you about purifi and i found icepower 700as2 better than it

[@giulianof8687]

Would be noce to hear some comments over the new XTZ A2-400......

[@christianbello2275]

Hi Thomas... I was wondering... How about Naim or Linn amps.... for reviews... Thanks.

[@chris292]

HII THOMAS!!!

[@AkilJacob]

Please don't make me get back into this hobby Thomas, it's not good for my pockets. I need a house RN! 🤣🤣🤣

[@ranbymonkeys2384]

House smouse, why have a house when you can have debt up to your eyeballs in things going down in value or completely smashed up against the wall with audio websites in your favorites folder deciding to get one thing or another picking the wrong one and your friends telling you it sounds like shit and then you have to bury his body of your friends in the back yard of the apartment you have because you don't have a house... well, I heard that's what happens.

[@AkilJacob]

@@ranbymonkeys2384 🤣🤣🤣

[@zsam5639]

Thanks for the great idea and experiment Thomas! May I ask your opinion on this diy kit (with original input buffer) compare to Starkrimson GaN Monoblock, which one do you recommend? Most my music are indie pop& rock and Audiomachine types, like clean but punchy bass. Thanks a lot!

[@ThomasAndStereo]

The GaN monoblocs were way more powerful, sharper and more airy. The problem is to match it to a good preamp else it can be bright. This Purifi is smoother, more analog but does not have the kick of those GaN. Think about it, the GaN monoblocks have 2 big powersupply, one for each channel while this one is driven by one powersupply. Now Purifi does have a monoblock version and the gap might be gone if I try the monoblock. Ultimately, it depends what you are looking for because they sound very different.

[@zsam5639]

@@ThomasAndStereo Thanks a lot Thomas. I'll go for Purifi then.

[@matthewhilty4209]

Isn't this what PS audio did with their high end class D amp ? Play with input buffers until they made one themselves.

[@JC-lk3oy]

Yes, the BHK's have a tube input stage. Paul probably has a video on the subject if you want more info.

[@matthewhilty4209]

@@JC-lk3oy I thought the BHK was class A/B not class D , I was refering to the top end of their "affordable" line.

[@ThomasAndStereo]

I know their monoblocs has tube input buffer.

[@maxb.simonsen2459]

You should check out Pascal class D modules, they sound really good.

[@asplmn]

You mentioned Class A/B -- do you think class D has reached a point of being able to compete with high end Class A?

[@ThomasAndStereo]

Class A sound is different than Class D sound so you would not buy a class D amp to replace a class A amp. Believe it or not, I would say most people don't like the class A sound.

[@asplmn]

@@ThomasAndStereo Oh, interesting. Based on what you see in the forums, you'd think everyone has a preference for Class A. :) Why do you think most wouldn't prefer it? (Granted, I know the majority of an amp's sound is circuit topology too... But that's relevant to the Class)

[@Audfile]

Bruno Putzeys is a legend!

[@PGHJR002]

On second demo the deep bass is a little lean, but, that may be due to the speakers. What is the rms wattage again on your Purifi class D?

[@ThomasAndStereo]

I think 280w. Lean sounding bass is normal, that is the class D bass sound.

[@gman76utube]

So, Thomas, you started off talking about a bi-amp system. Is Doge working on that? It will of course need an active crossover, likely redesign the input buffer board and include LR4 xover with adj freq. But then you'll need a target 2-way loudspeaker that can be bi-amp'd. And 60/40 split for low/high amp modules? Not sure how you'd bolt on the tube amp to all of this.

[@ThomasAndStereo]

No, the project was put on hold because it was too expensive.

[@arkdark5554]

Hi Thomas, I’d be most appreciated if you could answer my fallowing question: I got an Audioengine B1 DAC that connects my YAMAHA AVR. I listen music via Bluetooth on my iPhone. Now if I buy a Schiit Loki EQ, how do I connect it to my gear?

[@ThomasAndStereo]

I am assuming you are connecting to the DAC via bluetooth. It would be Dac to Loki to AVR.

[@arkdark5554]

@@ThomasAndStereo Thank you, Sir.👏👏👏

[@ranelime]

Thanks Thomas, very interesting! Do you think the upgraded Purifi with the KLH model 5 can be a good match?

[@ThomasAndStereo]

I don't remember trying it. I personally would prefer something less lean with KLH. I like the rich bass with KLH, perhaps I will try it someday if I get my KLH back, it is at my friend's place now.

[@ranelime]

@@ThomasAndStereo I'll report back in case I'll try it myself. Thanks!

[@dougg1075]

Very cool

[@roberthart9886]

Great idea, but IMHO tubes are not all that. Enter my Tweakaudio EVS 1200, based on2 IcePower AS1200 modules @ 1200 wpc and heavily modified by Ric Schultz. And most amazingly it was only $2300. Sadly, for the world, he only made about 14 of them. In front of it is a Oppo 105 with aftermarket LPM, WireWorld series 7 XLRs into my Audio Alchemy DPA-1 (dac/pre) + PS 5 outboard power supply for SACD and Pangea XL coax into the DPA-1 dac. Speakers are Emerald Physics 3.4s (12" concentric driver with 1" polyester tweeter and upgraded XOs. + 2 10 yo SVS powered 12" subs Plus and Ultra. Believe me no tubes needed.

[@ThomasAndStereo]

Nice, would love to hear it.

[@roberthart9886]

@@ThomasAndStereo Im in Ft Lauderdale. Come on down

[@roberthart9886]

@@ThomasAndStereo DO you have a website email that I can send pictures to?

[@scarecrow66ab]

Maybe you should try the nuprime sta 9 amp. I use it with a vincent 32 pre amp with the Focal kanta 2 and legacy audio signature se. I have two sta 9 amps that 290 watts into 4 and 8 ohms bridged. The amp is A and D

[@ThomasAndStereo]

Nice. One day.

[@PGHJR002]

Thomas, what do you think of the KORG Nutube? What do you think of its place in the future of hi fidelity?

[@ThomasAndStereo]

I don't know, I have to read up on it.