The problem, or limitations, with measuring vintage is that it is difficult to draw general conclusions from the results. Time and use wear things out, that's just the way it is. One may wonder how it affects test results. For example, this roughly 30-year-old NAD 2200 power amp.Amir:
The inside looks brand new! I have repaired hundreds of amplifiers but never seen one this clean! So not only have the inside components been updated/replaced, but a lot of care has gone into cosmetically cleaning the unit. Peter sent me a long list of parts he has upgraded including reservoir capacitors and such. As a result, I don't know how representative of measurements are of stock units although probably not too far off. Used 2200 go for about US $530 on ebay.
This is a review and detailed measurements of a refurbished and upgraded NAD 2200 stereo amplifier. It was bought by a member, sent to QuirkAudio to be fully updated and then loaned to me. The work that Peter has done is exemplary. The inside looks brand new! I have repaired hundreds of...
audiosciencereview.com
So how to interpret those results? The NAD 2200 is really good, but a NAD 2200 that has not received this extensive service, recap how would such a measure? Something that Amir also comments on:
Overall, I am happy to recommend the NAD 2200. I almost gave it the highest honors but given the upgraded nature of the test unit, and the fact that used amps may have issues, I avoided that. But you could have easily pushed me to give it the golfing panther.
Edit:
I know there is a craze for, for example, old receivers. Most likely, this can be attributed to their looks, but what makes the most sense is that you have knowledge and an interest/hobby to fix, service, repair, replace stuff etc.in old HiFi stuff. It will be needed sooner or later, probably sooner, and hiring a professional repairman who charges by the hour can be really expensive. That if you are really going to use old stuff. Otherwise, it can be fun just to read tests performed on vintage HiFi.