How do we remember 1970s amplifiers?


I would be curious to hear some of the memories and impressions associated with the following short list of 1970s amplifiers:

- McIntosh "first generation" SS amps, MC2105, MC2505, MC2300, MC250, MC2100
- Dynaco Stereo 400 and Stereo 120
- Phase Linear 400 and 700
- Bang & Olufsen "slide rule" receivers (i.e. especially blackface Beomaster 4000)
- Original Ampzilla (not Son of Ampzilla)

I've chosen this list mainly because they cover a wide range of approaches to solving the issues of early semiconductor technology, and they were all pretty mainstream products in the U.S. I'm excluding the Japanese receivers/amps not out of predjudice; it's simply that the circuit designs varied quite a bit with each model, and thus harder to broadly classify their characteristics.

I'm interested in impressions of both sonic and non-sonic attributes, and a preferred ranking of the above, if you like.
kirkus
So few remember the whole David Halfer kit thing. The Dynaco's were so good, Halfers were equally good to their time in SS. Hafler did OK but eventually got bought by Rockford Fosgate, who also owned Accustat. I forgot his name that designed all those Accustat TransNova amps, but (memory fuzzy) he was involved with Halfer later, wasn't he? I had an interview with Halfer in the 90's (they were all pro by then), in Tempe Arizona.

Hey anyone remember when Summer CES (high end suites) was at Hotel Congress in Chicago? That was about the early 80s and all those folks would be there.....the big companies where all at McCormick Place. In winter, it was Vegas and the Riviera for the high end and everything else was at (a much smaller) LV convention Center.
Brad

Either Hafler, or Dynaco could be transformed into true "high end" amps by simply substituting their existing parts for the best parts available today.

Successful businesses were created doing just that. When "Black Gate" capacitors were available, I replaced every electrolytic in every piece of equipment I own with Black Gates. That was with the exception of huge capacitors in power amps, but all other lytics in everything from reels to DACs were replaced with Black Gates.

If the replacement of a single part can upgrade a piece of equipment, imagine how replacing all of the parts would affect that piece of equipment. It's quite possible that some highly regarded "high end" amps are essentially "Haflers" or "Dynacos" with different parts.
"It's quite possible that some highly regarded "high end" amps are essentially "Haflers" or "Dynacos" with different parts." Amen.
I loved my Kenwood...KA-7100 of the late '70s.

Good with my 12" 3-way JBL 4311 clones from RSL....(SoCal Boutique brand) and later with my first panels...some MG-1s.
Since I was poor, I did a snip/snip....solder/solder and attached cables with RCA male ends and used just the preamp for another couple years with my first bit of hi-power amp, my old Carver Cube. Worked fine as a preamp.....

I still know where the amp is. I gave it away to someone who NEVER used it. I'm going to ask for it back. If they haven't used it in 20+ years, it'll never get used. Maybe a recap of the PS would be in order before pluggin it in?