Purifi or GaN class D with LPS

NoahH · « **on:** 2 Apr 2022, 09:40 pm »

Hi All,

I have recently redoubled my belief that overbuilt power supplies are the secret of audio quality.

Does anyone know if either a purify-based amp or a GaN class D amp that use overbuilt supplies? I struggle to find any using more than the Hypex SMPS.

Thanks!

Freo-1 · « **Reply #1 on:** 2 Apr 2022, 09:58 pm »

Most Class D amps use SMPS. Actually, many of SMPS are good performers. The power supplies for the Purifi, Peachtree Gan400, and the new GanFET from Atma-Sphere all have SMPS, and all are well received. It just comes down to a a matter of taste.

Linear power supplies can actually have a higher noise floor than a well designed SMPS. Benchmark has a white paper on the subject.

AndrewA · « **Reply #2 on:** 2 Apr 2022, 10:07 pm »

Atmasphere told me their monoblocks use toroidals.

AGD is the other competive brand. AGD definitely doesn't use LPS, but as Alberto Guerra designs everything himself I very much doubt his supplies are from Hypex. Lower-cost units will typically use off-the-shelf components. I am given to understand that the innards of the LSA Voyager and Peachtree GaN are virtually identical.

JCarney · « **Reply #3 on:** 2 Apr 2022, 10:15 pm »

Hi Noah,
Pascal Audio sells both modules and completed amps. They are one of the groups that split off from B&O ice modules development and pursued their own ideas. The link is for a completed unit, but the modules use the same power supply. From the spec sheet: "UREC™ universal mains switch mode power supply with Power Factor Correction (PFC) and standby converter." I have one of their 3 channel modules that both the input and output boards are modified and put in a very basic box with XLR connections. The modules are designed for balanced operation. It replaced Odyssey Audio Stratos Glass Ceiling mono's to give you an idea of how good I think they are.

Good Luck,
JCarney

https://www.pascal-audio.com/product/ip60-2/

NoahH · « **Reply #4 on:** 2 Apr 2022, 10:58 pm »

Quote from: Freo-1 on 2 Apr 2022, 09:58 pm

Linear power supplies can actually have a higher noise floor than a well designed SMPS. Benchmark has a white paper on the subject.

Benchmark is actually my nemesis brand. I bought an AHB2 when I first got my Wilson speakers, and it was the most soul-sucking piece of gear I ever heard. The amps in my AVR sounded better.

That experience made me not trust negative feedback any more and start to suspect power supply criticality after that. I am yet to find a counterexample.

NoahH · « **Reply #5 on:** 2 Apr 2022, 11:02 pm »

Quote from: AndrewA on 2 Apr 2022, 10:07 pm

Atmasphere told me their monoblocks use toroidals.

Just checked their site and they indeed say toroidal! I can't see any innards but given their tube pedigree, I suspect they are serious.

Definitely digging on that...

Freo-1 · « **Reply #6 on:** 2 Apr 2022, 11:22 pm »

Quote from: NoahH on 2 Apr 2022, 10:58 pm

Benchmark is actually my nemesis brand. I bought an AHB2 when I first got my Wilson speakers, and it was the most soul-sucking piece of gear I ever heard. The amps in my AVR sounded better.

That experience made me not trust negative feedback any more and start to suspect power supply criticality after that. I am yet to find a counterexample.

Ah. Understand. That's why auditions with your setup in your room are so important.

From your listening experience, maybe tube amps should be auditioned?

Freo-1 · « **Reply #7 on:** 2 Apr 2022, 11:23 pm »

Quote from: NoahH on 2 Apr 2022, 11:02 pm

Just checked their site and they indeed say toroidal! I can't see any innards but given their tube pedigree, I suspect they are serious.

Definitely digging on that...

Ralph is a good guy. Definitely worth checking out.

NoahH · « **Reply #8 on:** 3 Apr 2022, 01:59 am »

Quote from: Freo-1 on 2 Apr 2022, 11:22 pm

From your listening experience, maybe tube amps should be auditioned?

Yeah - I am lightly thinking about it. I tried an MC275 mk6 first thing and the speakers kicked it's butt. The impedence curve on my speakers is too complex for some speakers. But I am open to it. I do think something with a crazy damping factor will do the best though.

JackD · « **Reply #9 on:** 3 Apr 2022, 02:34 am »

Noah

Check out the Nuprime Evolution STA as it uses transformers and their own proprietary Class D circuitry.

https://nuprimeaudio.com/product/evolution-sta/?v=7516fd43adaa

Long time member John Casler is a Nuprime dealer and there are several owners on the forum.

Early B. · « **Reply #10 on:** 3 Apr 2022, 03:17 am »

It's no secret -- the sound is in the power. Ask Jaytor about his Purifi amps with fully tricked-out LPS.

Bottom line -- you have 2 options -- spend months or years rolling through several amps to find what you want OR realize that you'll never be satisfied and stick with an amp that's good enough.

Freo-1 · « **Reply #11 on:** 3 Apr 2022, 02:52 pm »

Quote from: Early B. on 3 Apr 2022, 03:17 am

It's no secret -- the sound is in the power. Ask Jaytor about his Purifi amps with fully tricked-out LPS.

Bottom line -- you have 2 options -- spend months or years rolling through several amps to find what you want OR realize that you'll never be satisfied and stick with an amp that's good enough.

Power is vital to obtaining good sound with many multiple driver speakers. I get outstanding reproduction from my
Tyler Acoustics Linbrook Signature, a speaker with five drivers per cabinet, using a Devialet Expert Pro 250. The amp has a lot of reserve power for transients. Also handles impedance variations with ease.

FWIW, also have a 100 watt set of tube monoblocks that actually drives the Linbrook Signature Floorstanders quite well. The amps have that full bodied sound the OP sounds like he's after. The 4 ohm tap works best.

mresseguie · « **Reply #12 on:** 3 Apr 2022, 03:41 pm »

NoahH,

I've hesitated to reply to this thread because my suggestion isn't a Purifi of Gan amp. However, since JackD mentioned it, I guess I may as well offer my suggestion.

Take a look at the Nuprime Evolution STA dual mono amp (or even the Evolution One mono amps). I've had an Evo STA in my system for 2 1/2 months, and I really like it. It does everything my KT88 amp does (warmth, power, soundstage, bass) but with greater clarity. My Daedalus Apollo speakers are <I believe> a much easier load to drive than your Wilsons, so YMMV.

I haven't heard a Purifi, Gan, or the AVA monoblocks, so I cannot tell you how the Nuprime performs against them. I did consider all of them before trying the Evo STA. [If I could just persuade Early B and Freo-1 to sell their homes and move to my city in Oregon, I'm confident we could establish a very rewarding visitation routine to all of our enjoyment!

] The Evo STA amp needed a solid 250 hours of burn in before I felt confident it had reached its happy place. Similar to JackD, my 'go to guy' for Nuprime gear is John Casler.

Enjoy your search!

Michael

NoahH · « **Reply #13 on:** 3 Apr 2022, 03:49 pm »

Hey Mresseguie,

Thanks for the note. I have actually read a bunch of your Nuprime thread. I appreciate you chiming in.

The nuprimes so sound interesting - your comments relative to KT88s make an even more compelling case. I need to see how I can try some.

As an fyi too - my Wilson's are not too bad to drive. The hard ones are my GR Research NX-tremes. I like them a lot as speakers but the impedence curve, below, is rough.

Freo-1 · « **Reply #14 on:** 3 Apr 2022, 04:19 pm »

That is quite the varation in impedance. I would be tempted to look at the Pascal boards from D-Sonic. 1500 watts per channel would easily overcome the wide variations of impedance.

I.Greyhound Fan · « **Reply #15 on:** 3 Apr 2022, 04:45 pm »

I would also look at PS Audio M1200's and M700's. 1200wpc and 700 respectively.

AllanS · « **Reply #16 on:** 3 Apr 2022, 06:03 pm »

Quote from: I.Greyhound Fan on 3 Apr 2022, 04:45 pm

I would also look at PS Audio M1200's and M700's. 1200wpc and 700 respectively.

If you don’t mind, I’m curious why you’d recommend these.

NoahH · « **Reply #17 on:** 3 Apr 2022, 06:18 pm »

Quote from: AllanS on 3 Apr 2022, 06:03 pm

If you don’t mind, I’m curious why you’d recommend these.

I am curious too. Also, I know you were taken with the AVA M225s; can you compare your experience to those? I am actually returning a pair of those right now as I felt like they were 'fine', but without the weight and body of a good class A or the detail of a good class D.

I.Greyhound Fan · « **Reply #18 on:** 3 Apr 2022, 08:43 pm »

Quote from: AllanS on 3 Apr 2022, 06:03 pm

If you don’t mind, I’m curious why you’d recommend these.

My son bought a pair of the M700's and they sounded much better than the Parasound A21 that I gave him. More detail, smoother, wide sound stage, more air and transparency. Better bass and top end.

As far as the M1200's are concerned, I have not heard them but a good friend of mine who owned the M700's traded them in for the M1200's and he says that the M1200's sound a lot better. And he raved about the M700's. The 1200's is a tube hybrid. His system consists of a Parasound JC2 preamp, PSA Direct Stream DAC and PSB T3 speakers. Unfortunately, he moved to New Mexico, so I have not heard his system since he moved up to the 1200's.

https://www.stereophile.com/content/ps-audio-stellar-m1200-monoblock-power-amplifier?msclkid=b2301a2bb38d11ecb03a180c9f12c249

If you do not need the power, you may want to consider the new Atma-sphere Class D monoblocks. Rumor is that they sound better than his top end tube amps. I may get to hear a pair sometime in the next few weeks. A buddy of mine owns a pair of the MA-1 amps and an MP-1 preamp. He may get a pair of the Class D mono's to compare to his MA-1. If so, I will get to hear them.

Freo-1 · « **Reply #19 on:** 3 Apr 2022, 11:29 pm »

Sounds like the OP has a number of options to investigate. After looking at the impedance curves, I'd initially go for as much power as possible, irrespective of linear or SMPS. There has been good feedback on the 1500 watt D-Sonic, as well as the M-1200.

I'm surprised the GR Research speaker has such a wide variation in impedance.

Let us know how you go with this.