best vintage 70s, 80s amp?

Aragon showed their new amps at CEDIA. They looked good. Aragon has been purchased from Klipsh.

http://www.audioholics.com/news/industry-news/aragon-acurus-indy-audio-labs

Great American Sound (GAS) Ampzilla series, the Son of Ampzilla in particular.

I always liked the Hafler DH-220 amplifier and if you can deal with the fan noise a Sumo Nine or Sumo Nine Plus. Either of these amps will keep you warm at night. Especially the Sumo Nine.

Good luck with the search.

There seems to be some confusion about Aragon and quality because Dan D'agostino had something to do with the design. However, Aragon has more in common with Adcom than Krell.

There are too many good sounding amplifiers from the '70s and '80s like Krell, Mark Levinson, Threshold, Audio Research, Quicksilver, Robertson and Dynaco are just a few that come to mind.

I own a Pioneer Ser. 20 M-22 30W Class A amp(late '70's vintage) and the sound is incredible. If you don't need a ton of power and don't mind the heat, it's hard to beat. Very detailed and musical, with great bass and holographic imaging. Not the easiest thing to find, but worth the search.