Bought a Krell KSA250 32 years ago new. Great amp that still sounds good with the right speaker. 140 pounds of finesse/muscle. On a wait list for complete restoration.
Had an original KSA50 before that. Also a wonderful amplifier.
Build quality of those amps resembles that of $50,000 plus products of today - actually more. Can't afford new stuff in that category, so compromised on a set of new Pass class A mono's.
Don't even think about new Krell amplifiers, totally different product. YMMV