Anyone interested in ATI should check out
Classic Audio Parts, who is an authorized seller so you get the full 7 yr warranty.
As mentioned, ATI has been around for 30 years. The amps are made in California. But they are kind of quiet.
When HTM reviewed the Revel Salon2, they asked Kevin Voecks to select an amp from HTM's inventory to pair with the Salon2. Kevin Voecks selected a 150wpc ATI amp. Yes, 150 watts per channel ATI.
They are sworn to secrecy. Literally. Legally.

Understandable for economic reasons.
But words have been tossed around that ATI has made some amps for Mark Levinson, Lexicon, JBL, Outlaw, Cary Audio, Cinepro, Earthquake, and now Theta and B&K since ATI has acquired both. Of course, the built specifications may slightly vary for each company, but the core is still ATI.
The specs of the ATI amps are impeccable: -123dB SNR from 20Hz-20kHz, -100dB crosstalk from 20Hz-20kHz - note the full spectrum spec, instead of the 1kHz spec. And their power ratings are very conservative.
I just bought a brand new pair of B&W 802D2 piano gloss black (ETA next Monday). The owner of the dealer asked me what amps I will be pairing with the 802D2.
I told him "ATI".
He said, "ATI is okay, not the best, but okay".
I said, "What do you think about the amps from Mark Levinson, Lexicon, Theta, and Cary Audio?"
He said, "Oh, now those are awesome, definitely among the best!"
I said, "Well, ATI makes some of the amps for all those companies on the inside".
He said, "Oh, really, I had no idea!

"
Edited by AcuDefTechGuy - 8/2/12 at 4:57pm