Class D ICEpower 1200as2 vs. Purifi 1ET7040SA amplifiers


Has anyone compared the ICEpower 1200as2 vs. Purifi 1ET7040SA amplifier in their hifi setup?  Legacy Audio uses the ICEpower module in their i-V2 Ultra and Doug Schroeder did a nice review on it.  I first read about the i-V2 Ultra in Doug's review on the Pure Audio Project Trio15/Coax10 review.  I just ordered these speakers, so I am interested in this amp.  I researched a myriad of class D amps and I've narrowed down my interest to the following; GaNFet (AGD Audion), Purifi (Apollon w/Sparkos opamp), MOSFET (Bel Canto REF601M) and ICEPower (Legacy Audio I-V2 Ultra). 


I know ICEpower modules are older class D technology, but if they are equal or outperform the latest offerings, that's all that matters to me.  Plus, I understand they are reliable as they have been around for a long time. 


I owned PS Audio's M700's and S300 amps which use ICEPower modules and they sounded really good, but I sold them several years ago to explore the world of tubes.  I'm back to solid state now and interested in the latest class D offerings.


Any impressions/experience with the icepower 1200as2 vs. Purifi 1ET7040SA amplifiers are welcomed.  I've already read good reviews on both of them, so a comparison between the two would be most helpful.  In addition, let me know if you have compared any of the class D amps in my list in the first paragraph.  I understand I need to hear them for myself, but I still appreciate your opinions!


Thanks in advance


@markmuse 🤣 That was funny!!!  I understand that.  The ears have to be ready to receive the signal to properly judge it.  

Let me know if you get the Atmasphere amps in house to do a shootout with the AGDs.


Wish I could say. Last time I had the Atma-Sphere's here I still hadn't a decent pair of hearing aids. Got that fixed now - Widex: best audio system upgrade to date!


@lewinskih01 Yes, a speaker manufacturer did recommend Atmasphere class D amps sometime ago.  I’ve had PS Audio M700 monos, S300 in a second system, Prima Luna EVO 400 preamp and amp combo, then moved on to the Luxman L-509x integrated.  I sold all of them and using a HEGEL H160 integrated from my second system until I decide on another amp.


@markmuse I do believe the PAP 10” coax driver will be the ticket, so I’m looking forward to hearing them.  So, you are still contemplating pursuing the Atmasphere monos to possibly replace your AGD amps?  If so, what do you feel the Atmasphere does better?




The horn loaded HF driver in the X5 is really good, just the vertical dispersion issues. The Pure Audio speakers look interesting. Bet the dispersion is excellent with the mid/HF concentric driver you got with a larger sweet spot. 

One thing I should mention is the Pass XA25 with the X5 was truly magical.

And I second the Atma-Sphere GaN monos. Definitely worth an audition. I did audition them (twice!), and I might still revisit that decision. 


First, the LSA was way too much power for my situation. It is a bit warmer than the AGDs, a little less detailed and refined throughout the range, less transparent. But still a very good amp in my estimation, especially given the price. 


AGD certainly gets high praise consistently. I believe the Tempos are around $5k and at that price point another GaN amp that gets high praise is Atma-Sphere class D. You can search comments in this forum about how owners of Ralph's tube amps have switched to his class D. It's also a stereo chassis, larger than Tempos I think. I haven't owned (nor heard) Atma-Sphere equipment but Ralph (who is active in this forum) is certainly knowledgeable and gets good comments on customer assistance (two traits you noted are valuable to you). Worth looking into, I think.



Could you please elaborate on the differences in sound between the Tempos and LSA Voyager? It's clear the Tempos are better overall, in line with the price differential, but I'm wondering if the differences you noted were centered around bass, midrange, treble or other.

@markmuse Interesting….  I had a different experience as I prefer to sit down and listen to my system, so I never considered how the X5s sounded outside of my listening position.  Now, I did try several positions with them and found that they had a large center stage when the AMT tweeter was positioned about 1 to 2 feet outside of my shoulders.  That waveguide used for the AMT tweeter gives a nice wide dispersement and they were supposedly known for giving a wider center stage over a Martin Logan electrostatic speaker, as an example.  So, several X series owners on the Spatial Audio (Audio Circle) forum tried that towed out positioning with success.  My issue was with the thin midbass, lack of bass and the top end was in my face on certain tunes.  The subwoofer would start clipping on some bass heavy tunes, but the fully passive models, M and X series had better bass over the hybrid X5 IMO.  Again, I preferred the Pure Audio Project this time around as that Coax 10 midrange driver has been praised for delivering beautiful midrange and that’s where the music lives in just about every music genre!


I’m glad the Fyne speakers are working for you.


@dbt Re the X5's, they were really excellent in many ways, but 1) the imposing size of the speakers was an issue (ruled out Maggies for the same reason); 2) the sweet spot was really small, like head in vise small; 3) horizontal dispersion of HF was pretty good, but vertical was like none. Stand up and the character changed a lot. My system is in an open space that incorporates kitchen, dining, and living areas. I often listen while cooking, reading, cleaning, etc., so the X5's didn't fit in well. The Fynes with their concentric drivers are ideal for this kind of space and style of listening. 

@markmuse Your experience with the AGD amps powering your Fyne speakers with a sensitivity of 91db, with ease, lends further confirmation to my position on being content with the 100w into 8ohms AGDs paired with my speakers!

Spatial X5?  You’re good…..  Very close, but no.  I had the X5s, sold them late last year and planned to buy the fully passive Spatial X4.  However, I decided to buy the Pure Audio Project Trio15 w/Coax10” driver.  Similar design philosophy, but I want to try the PAP design this time around.

I don’t want to sidetrack my post topic too far, but what caused you to swap out the Spatial X5 speakers?




BTW, on a whim I recently bought a used Pass XA25 (still sitting on my dining room table) to compare to a single Tempo. Granted, the Fynes are an easy load with a minimum impedance of 6 ohms, but still a single Tempo was smoother and more refined, with just as much grunt as the Pass. Two Tempos and it isn't even close. 

Regarding power requirements, my speakers (Fyne F1.8) are 91db, my room is 25 x 25 x 8, and I don't come anywhere near exhausting the headroom of the Tempos. At 97db you will have gobs of power with either the Audions or the Tempo. 

I would suggest that unless you want to bi-amp I would get a pair of Audions instead of a single Tempo. Imaging will be better. 

97db? What did you get, Spatial X5? I had a pair at one time. 

To All:

You guys have provided a lot of good information with your experience and impressions on different power amps!  Unfortunately, I can’t get my hands on all the different amps you all mentioned, nor would I want to go through that many auditions.  Lol….  I’m narrowing my choices down to what I really want to try.  If I had to make a decision, TODAY, without hearing any amp, I would choose the AGD Productions Audion mono blocks or possibly the AGD Tempo stereo model.  That’s about the only class D or any class of power amp manufacturer that I haven’t read or heard any negative feedback.  Everyone describes it as a transparent amp that has a touch of bloom like tube amps, while retaining the bass, air, detail, smoothness and grip on the drivers.  That’s a big deal to me and that’s what I’m looking for.  The field upgradable output stage in a tube is a brilliant idea as well!

I originally wanted more power than the AGD Audion monos offer, but my soon to be delivered speakers sensitivity spec of 97db should do just fine with the AGDs.  I spoke with the AGD owner/designer and he is a really talented and smart guy with good customer service.  That’s a good start.


Today, I spoke to a representative from Legacy Audio concerning a few questions about their I-V2 Ultra amp.  I asked about the humming noise some advised they heard coming from the actual amp, not their speakers.  He advised they do hum sometimes whenever they are not properly grounded during the build process, but they test and fix, if needed, before shipping them out.  The reviewer of this amp advised of the humming and someone on this thread mentioned the ICEPower 1200as2 modules sometimes hum as well and that scenario was in residence, not the factory.  Shipping the unit back in forth for repair is not something I want to deal with right out the gate with a new amp, but I am considering it.  Legacy doesn’t offer an in-home trial, so that may not be the ticket for me.


I’m in no rush because my speakers require about 200 hours to break-in, so I won’t audition any amps until the speakers are performing at their best.  I don’t want any excuses for my speakers.


Thanks all for your informative feedback and feel free to add any information you feel would be useful concerning class D amps and any comparisons you experienced.  This is a fun journey, but it’s not free! 😎

I seriously doubt PSAs M1200s are using the 1200 AS2s, most likely based on the 1200 AS1s


But it's not just a standard AS1s.  According to reports it was modified by PS Audio (with IcePower guidance)  to marry it to a tube input stage, for better or worse. 

I would suggest trying one of the Axiom Audio ADA series amps. The have amazing amounts of headroom and are very neutral, detailed and open sounding with none of the typical Class D harshness. They use a massive transformer and a lot of storage capacitance. I believe they have a 30 day in home trial. I am using a 4 channel one in a tri-amp set up and love it. They do not use the ICE chips, they use their own patented set up.

I have a pair of ESLabs DX-S4 which I've been happily using for over 5 years, although one is broken due to a mouse pissing on the board when I had the top off! I'm using one in stereo mode to drive my Maggie 1.7i's, and it sounds really good. I've compared it with several other well known, high class amps, Class A/B and A, and it sounds better than amps costing several times the price of the ESLabs which when they were new, were about £1750 each. They're probably 15 years old now, but still sound great. ES actually call them Class T, as they use a Tripath module to drive two pairs of MosFets - one pair per channel, at 180w into 8Ω, 300 into 4Ω and 200w into 2Ω. In bridged mode it gives 500w into 8Ω using all four output devices, and double the current.

Ignore people who say Class D is rubbish, as they've probably not even heard any!

I have been using class D for years now: Jeff Rowland, Bel Canto, LSA Voyager, and settled on two AGD Tempo stereo amps to bi-amp. Very pleased with AGD fed by a Backert Labs Rhythm line stage. 

I believe the Rowlands were ICE, but unfortunately I used them bridged which was not their best.

The Bel Canto 600 monos were very rolled off from the upper mids to the hi frequencies. Kind of a lifeless presentation.

The Voyager (GaN) is surprisingly good for its price.

The AGDs (also GaN) are great all around, smooth, dynamic, neutral, resolving. Love them.

FYI: the ICEpower 1200 AS1 is a mono module, the 1200 AS2 is a stereo/2 channel module

I have enjoyed a Tweak Audio EVS 1200 (dual 1200 AS1s , no tube input) for a couple years now. The twin mono modules are modified by Ric Schultz

I had the PS Audio M700s for maybe 4 months. My room is physically and volumetrically large, the M700s were underwhelming in it even though my Emerald Physics 3.4s (open baffle) are very efficient. The EVS 1200 rocks the room.

I seriously doubt PSAs M1200s are using the 1200 AS2s, most likely based on the 1200 AS1s

I also have a LSA Voyager GaN 350, which I like even better, but when moving from a vertical to horizontal rack. The lid was resting sideways to top. The amp slipped off a cushion and the lid crashed into one module. When I had all my kit in place and connected I turned the amp on to a 4th of July fireworks in one GaN module, so the EVS 1200 went back in. Occasionally I hear a bit of hardness, that was not present in the Voyager


Make sure to choose a class D amp with lots of head room like 800w in eight ohm.

You may also want it to be stable in 2 ohm.

And don't pay too much for boutique brands.

Yes, the "war" is now between different class D constructions. Myself I use a Storm PA 8 mk2 which is terrific.

I have owned the AGD Audions for the last couple of years paired with a Supratek DHT pre and i could not be happier. The music comes to life with a satisfying musical experience.

I moved from Primaluna integrated to Bel Canto 600 and ended up with AGD Audions.  Could not be happier.  The Primaluna seemed to be lacking headroom, Bel Cantos no life but the AGD had what I was looking for.   I still have tubes is the path as I use a Cary SLP-05.  End game stuff at my budget in my room.  Could not be happier.  Balance of system - Bricasti M1 Series 2, Joseph Audio Perspectives.  

I hope to have an A/B comparison of several popular class D amps at the PNW AudioFest June 23-25th in Seattle. Come by for a listen!


One other consideration is that the power section on the 1200as2 board has known to hum based on flaws on its design. When units exhibit this issue, the hum is low but can still be heard from a few feet away. It may be enough to slightly vibrate a chassis. 

I own a Minerva PurePower SE for my office / desktop setup, which uses the 1200AS2. It was also in a second system prior used with a variety of speakers. I also own the T+A A 200 amplifier which uses the Purifi Eigentakt modules. Of the two, I find the T+A amplifier to be perfectly linear AND smoother. The 1200AS2 in the Minerva is really clean, but its top end is a little sizzly and the midrange is thinner. The T+A A 200 with Purifi sounds much more natural. 

@jbuhl I didn’t know the PS Audio 1200 was using the 2200as2?  Thanks for that information.  I really like PS Audio customer service, but I had an issue they couldn’t resolved with my Stellar Gain Cell DAC, so I don’t think I’ll be going down that road again.


Don’t visit PS Audio unless you want to have a pair of mono blocks loaded up and ready to take home because I’m confident they will impress you!😆


@erik_squires I literally just sold my Luxman L-509x last week.  It was very nice, but I plan to go back to separates, so I sold it.  I’m using my HEGEL H160 until I settle on a new amp to pair with my Holo Audio Serene KTE preamp.  Shockingly, the HEGEL sounds as good as my Luxman, but the Luxman has more sparkle on the top end.  The HEGEL manages the bass much better and a little warmer than my Luxman.  I loved my Luxman, but I don’t miss it.

OP:  That was like 8 years ago!! :)  So I considered the entire class warfare of amps over with.

Mind you, I did go to Luxman eventually, but the issue of "it sounds like Class D" was nonsense.  My ICEpower beat out mega-buck Class A as well to my ears.  My Luxman beats both, but the point is, Class D is great, and you should feel confident when you find a Class D amp you like. 

The PS Audio M1200 is 1200as2 Tube hybrid.  12AU7 input stage.  I would really like to hear a pair of those with my Mullards in there.  I ran the S300 fronted by a Rogue RP-1 for years to good affect. 

PS Audio is just down the street from me and I am afraid to go over there 😀




@erik_squires I appreciate your feedback.  I’ve been getting that type of feedback from a lot of reviews and forums concerning the latest offerings from class D amps vs. owner’s expensive solid state or tube class A & AB amps.  So, it’s good to hear the technology is improving!



I have to tell you I could not tell my ICEpower units apart from the Parasound Halo amps I bought, so I sold the Parasound. :)