Adcom circa 1990 amp and preamp

I went to a local vintage audio shop here in rural PA to get a cheap system for my basement. They had an Adcom 565 preamplifier and a 545 type 2 amp. Back in the day I had a 545 coupled with one of their tuner preamps and the latter was not so great. I hooked the new setup to my Larsen 6.2 speakers and Rega Apollo CD player and was shocked at the quality of the sound. The pre is amazing with more than satisfactory phono and headphone capabilities. The Adcom sounds wonderful and now I am using it as my main system for a while. Ok, a tube fan might complain the treble is a trifle harsh but that is mere opinion, and nothing a Black Ice tube DAC can’t cure. I also got a pair of Polk Audio Monitor 7s and they are amazing. 
My main system is the Exogal Comet/Ion that cost thousands of dollars. I love it but the new vintage system holds up quite well and cost $700. Am I crazy or what? 
I think that a part of your reaction relates to nostalgia.

I also owned some nice, early Adcom gear, and certainly have fond memories of the systems that I developed back in the '80s and '90s. But at the same time, while vintage components can certainly sound good, the advances in technology since that time have been significant.

Not long ago I was using a re-capped Accuphase 303x integrated amp, and it sounded terrific. But when I switched to a (used) Hegel h160 amp, which cost about the same as the Accuphase in current dollars, the difference was striking. Both were connected to an older, but excellent Electrompaniet CD player, and Harbeth speakers.

Not to say that I couldn't be satisfied listening to a vintage system, but I do also appreciate the gains that have been made, and especially now with regard to DACs.
Here's what I put together from my vintage collection and am now listening to: RGR 4 preamp/ Sumo Andromeda amp/ DCM Time Windows. Sounds really excellent with my analog and digital sources! And for you wire fanatics the speaker cable is Q Audio Time Stream (bought used).
Sounds like some good stuff. Certainly I have a degree of nostalgia but if that were the dominating factor I would be into receivers. People tend to equate quality in audio with dollars spent and I have to say that I could live with this Adcom stuff quite easily, especially since one system cost 8k and the other $700. Adcom is considered to be a real classic by many, especially the amplifiers from this period. You don't see too many 565 (but lots of 555s) preamplifiers around presumably because people keep them. I was thinking to get something more modern but from the sound point of view there really isn't any motivation.

I was in Robert's basement on Howard auditioning stuff. Grodinsky designed great pieces. Cheap switches and all.
I'll bet it sounds fine pushing the Sumo.

A system doesn’t have to be perfect to be engaging and enjoyable. It doesn’t even have to be accurate. The Adcom stuff was very good for its time, and I’m not surprised it’s fun still.
Doesn’t surprise  me either.  I have plenty of friends with current high end rigs, and I personally think my system has more touch, tone and feel than anything my buddies own. 
I don’t really think that ‘new technology’ has advanced good sound to where it has  made ‘old technology’ out of date.  
Good sound is good sound regardless of what era or technology it comes from.  To think otherwise is kinda silly, isn’t it?
Hafler is another example of this phenomenon. Their amplifiers are very highly regarded by knowledgeable people. I have some new high quality components but would have no problems sticking with Adcom and Hafler. And now you can hook up your DAC to the amp and use it as a preamp and get all the benefits of streaming. 
Adcom was very successful for a reason, full stop.  They still make amps, btw, and are still very capable products.   I have the GFA 565 SE being driven by a very transparent tube preamp, and the combination is jaw dropping at times.

The Adcom GFP565 was their top of the line preamp.  Up until just a few years ago I was running a B&K ST-140 amp with an Adcom GFP555II preamp, and it still sounded good.  
It is really amazing to me how good all this old stuff is. I use a DAC now as a preamp so this isn't seeing much use. I used to sell Adcom while working through college--back then we used to sell it with Irving Fried's speaker line or Missions, usually bi-wired with Canare cable. The Fries were superb also.