20 Year Old Amplifiers compared to 2017

My take is that this one of the most informative threads on AG in a while with very thoughtful responses. I recently got an First Watt F5 amp, my first Class A amp, and it is a glimpse into music that I had never heard before.  I dunno if all pure Class A amps have similar performance to the F5, but it is the pinnacle of amps I have had over 45 years.  It is not as powerful as my McCormack DNA .05 amp, a Class A/B amp, but between the two of them, I am very happy.  I would be very keen to find an upgraded Krell KSA-250... it is the one Class amp for which I lust. 

I am a denier of the SQ benefits of Class D amps, but I have not heard the best of them. The ones I did hear seemed to be bereft of the total musical involvement I enjoy with Class A and Class A/B amps.   I am a lover of vintage gear myself.  Again, this a great and informative thread. 

I imagine that Nelson underclocks the First Watt amps to prevent them from competing with Pass Labs. 

My Julius Futterman OTL3s are circa early 1980s. I recently had them converted from pentode to triode, and replaced all the caps with Jensen foil oil caps. They were tuned to my Altec 694Cs and to my room. 

I cannot imagine anything sounding significantly better for the money.

Good thread. I have an old Proceed Amp5 in need of TLC sitting around, that I've been debating back and forth about investing in a rebuild. It functions, but it's not working at its potential. Anyone have any thoughts?

I would think, that when comparing an older amplifier to newer designs, isn't it also essential to be certain that it still functions optimally? Maybe that's a dopey statement, but after 20 or more years, it's easy to neglect it and forget it might need refreshing.
In the case of my amp, it needs a good refurbishing, so I wouldn't dare compare it yet to anything.