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
My memories of the Dyna 120: BANG! Blew up all the time; warranty repairs drove Dynaco out of business. I remember them more from the middle 60s. I had an SAE but my Quad 303 was a better amp.
I think my ability to afford higher end gear was transitional in that decade. My memories are limited to the early 80's and NYAL which was my first experience of the warm, lush sound of tubes, along with the Dynaco 70. What I have set in my memory of those is what I'd describe as a more romantic sound...certainly colored, a bit mushy perhaps (what a horrible adjective to apply to audio reproduction, but it's more an emotion I'm after there). I doubt I'd like them if I heard them today, but who knows. I was completely unimpressed by muscle amps like Phase Linear - they just gave me a headache. Now there were some Krells from that period, and perhaps a Levinson, that really turned my back around to seeing what SS could do right without the associated headaches.
Some model Yamaha receivers were very good for the small amount of money they cost. A few were as low as $149.00 or $199.00 including tuner.

BGW was a great amplifier for commercial application, a southern California company that came to market about 1971 as I recall.

I sold a few to "rock and roll" stereo customers, certainly it was a superior sounding product than the Phase Linear that was more popular at that same time.

http://www.bgw.com/about/

Dave O'Brien of McIntosh clinic fame tested lots of Kenwood KA6000 and spoke highly of them. About 50 watts per channel at multiple output impedances and sturdy power supply.

Link below shows it with matching tuner of same era.
http://www.mcintoshaudio.com/images/kenwoodpair.JPG
My first excursion into the "high-end" came in 1984 when I stepped up from my Fisher X-101 with Sanyo turntable (other components?) to a McIntosh system. I purchased a used C-26, MC-2505 and new XL-10 outfit, along with a new Thorens TD-146 with Signet TK3A(?). I was so sure that McIntosh was the ultimate that I don't even recall listening to the system before bringing it home.

To make a long story short, I really tried to like it, but to my chagrin it really didn't do it for me. It seemed muddy and uninvolving. This stereo stuff wasn't as easy as I thought!

Oh well, that began my (futile?) search for the holy grail of audio!!
A friend found the Dynaco Stereo 400 on a thrift store, rated at 200wpc into 8 ohms, 300wpc into 4 ohms. A beauty, but this one needed several fixes. Some people say its harsh and grainy.