Threshold s/500 vs Cambridge Azur 851 CD

I am saying there has been tremendous advancement in technology over the last forty years and buying really old stuff is not a great way to build  a great sounding system. While buying used can be a great way to reduce cost… usually not older than 10 years… but, it depends.

The Threshold s500 was the very best available amp period… in 1979 (in todays dollars ~$18,800). I bought one. It absolutely bested any amp of its time. When I sold mine about 20 years later and bought a Pass X350… the Pass made the Threshold sound like it had little power and the sound was very tin like. I kept the Pass for 20 years and when I replaced it a couple years ago with my current amp… while the Pass did not sound gutless it sounded very thin and in-evolved.

The improvement in sound quality has been astonishing.

Need some idea what you are trying to do… budget, your sound preferences. Actually putting photos of the system under your used ID will give us something to work with.