Frank loaned me this amp so I could write a review and compare it to my Pass Labs X250 amp. I have had it hooked up for 2 days now and I am very impressed. The SET 400 is 225wpc at 8 ohms and Frank says it will double its power at 4 ohms. My Pass amp is 250wpc and 500wpc respectively at 8 and 4 ohms. The rest of my system consists of a BAT VK-51se tube preamp, Luxman DA-06 DAC running with a Regen powered by a Terdak LPS. Music source is a dedicated audio headless desktop custom built computer. Music player is Bug Head versions 8.6 and nontallion 10.04. Cables- WireWorld Starlight Red usb, Cullen Gold Power cord (amp), AQ Columbia 72v XLR's and Belden 8402 XLR's. Speakers are Magnepan QR 1.6's.
My dual Martin Logan subs were turned off as the SET 400 is single ended and my system is fully balanced, so I had to use my female XLR adapters from subs to use with the amp. To keep apples to apples, I listened to the music tracks with my Pass Amp without the subs.
Now for the sound. With the very first few notes, my son and I looked at each other and said "Wow, this sounds great". As we listened to the first album, Anne Bisson's Blue Mind, it was very apparent that this was a special amp. I hate to use audio cliche's but the sound is very natural and organic. It has great musicality and is extremely smooth and liquid sounding, more so than my Pass amp. However, it did not round the edges off like the Pass. Leading edges or attack if you will, were a tad crisper in a good and more natural way. The overall tone leaned just a shade to the warmer and darker side, although my BAT preamp may be responsible for the dark sound for those of you not familiar with the BAT sound. I also have my settings in Bug Head to lend to a slightly warmer, darker sound. Bass was deep and very well controlled. Drum kicks were powerful and convincingly real. There was just a hint of low end bloom contributing to the rich toned mid range and musicality. Speaking of the mid range, this is where it is at with this amp. It is tonally rich and there is good texture. Vocals and horns are full bodied. Piano sound delicate and full bodied at the same time. The notes had excellent decay. There was no harshness or glare. High frequencies like cymbals had good air and sounded real. Sibilants were tamed as well. For those of you familiar with Blue Coast Records, "Blue Coast Collection The E.S.E Sessons", Jayne Selke's song "Slow Day" is as sibilant as they come and the SET 400 did a great job of taming them without sounding rolled off.
Where my Pass amp had the edge was in texture, air and sound stage. The SET 400 has good texture, air and transparency with a wide sound stage but my Pass had more. The sound stage with the Pass extends beyond my 17' wide room and there is more front to back depth. Female vocals, horns and piano had a bit more texture. There was just more separation between instruments and vocals. Now don't get me wrong, I am not saying the SET 400 is bad in this area. It actually excel's in this area but the Pass just does it a bit better. But I would expect the Pass to at its almost $7,000 price point vs $2199 for the SET 400. I also own a Parasound A21 amp which now sells for about $2300. The A21 does not even come close to the SET's performance. The A21 sounds midfi in comparison.
I have to say that the SET 400 is my favorite AVA amp (although I have not reviewed the DVA 850 mono's) and on par with the R series amps. Tonally, the SET 400 sounds completely different from the R series amps.
If I ever have to replace my Pass X250, the SET 400 will be high on my list as a replacement.
Highlights of the amp are-
To die for tonally rich and musical mid range
Organic sound, smooth and liquid
No glare, grain or edginess
Tight, controlled, powerful bass
High frequencies like cymbals have good air natural sound.
Plenty of power
Black background with no detectable hiss.
Low points- None at this price point. I really could not find fault with the amp.
Music used for review purposes-
Charles Llyod and the Marvels with Lucinda Williams
Anne Bisson- Blue Mind
Blue Coast Collection- The E.S.E sessions
Paul Burner Band
Chris Jones- Roadhouses and Automobiles
Nils Lofgren-Acoustic Live
Sara Barelles- Brave Enough
Eva Cassidy- Live At Blue's Alley
and a few others
I did some listening last night and I decided that I really love the sound of this amp. The mid range, musicality and liquid sound of this amp is intoxicating. I could listen to it if for hours without fatigue. It definitely conveys the emotion of the music. I could certainly see this amp selling in the $5,000 to $6,000 range in stores.
I also changed some settings on my Bug Head music player to a more neutral sound and was able to remove most if not all of the darkness. My BAT preamp certainly contributes to the dark sound and my Luxman DAC leans to a slight warmth.