Has this happened to you? How can it be stopped?

That Harmon Kardon 730 receiver was an excellent piece of equipment! Assuming it’s functioning as originally intended, I’ll bet within its power ratings, it sounds better than any receiver today & can hold its own vs many amps that don’t cost crazy $. 

@mapman 

I have a 1917 Victrola which works great, it is a rather pedestrian model as in the horn is internal and has two front doors that the volume control.  It is in beautiful condition and plays amazingly loud.  I bought about 300 78s.

Whenever I'm thinkin' the main system is not working correctly (not sounding its best) I play some 78s and well that clears up those thoughts real quick.

Regards,

barts

I have one great rig [I think] in one dedicated room and do not need anything else beside a tabletop Echo at all. It makes it special to me.  Just sayin.

There is a flaw in your question. It has never been about "need"! 

I would think audio gear has gotten better over the years.  It all depends upon your ears.  Many of us experience high frequency loss as we get older.  I would think amplifiers have their own sound and for that matter so do speakers.  I know I have hearing loss in the higher frequencies and I would like to buy new speakers that have brighter more detailed tweeters.  The big question is do you upgrade the amplifier first or the speakers.  I would think to hear optimal sound you would have to upgrade both.  I would think as we get older we need to reevaluate our systems and fine tune things to our ears.  I for one would like to upgrade my speakers and amplifier.  However, there is also the wife factor.