When were the best tube amps made?

Modern tube types, like KT 120, KT 150, and KT 170 deliver more power, but to my taste, they don’t sound that good.  I like much lower power alternatives, but of course that means having speakers suited to lower power.  I will take a modern or vintage 6L6 or KT 66 amp over amps capable of running higher power types.

You can find great tube amps throughout the time they have been made.  There haven’t been any technological breakthroughs in recent decades that render older models mere outmoded.  One of the best I’ve ever heard is the Western Electric 59A, which is from the early 1930’s.  I also like Western Electric 124 and 133 amps.

I have heard a few good OTL amps from the 1990’s to current times and these might be considered more “recent” in design than most tube amps.  The quasi-OTL amps, like Berning’s ZOTL amps, represent a sort of modern innovation, but, I personally don’t much care for the sound of the amps I’ve heard.

Most of the parts in tube amps have not been improved much in a very long time.  The best output transformers from the past remain highly sought after because they sound better than most currently manufactured ones (e.g., Chicago, Accrosound, Western Electric).  The same with tubes themselves—many older tubes sound better than current versions.  Perhaps some newer parts, like teflon caps, are an improvement in certain applications, but, in many of the amps I really like, old parts, like some paper-in-oil caps sound very good.  Some current manufacturers make great new parts, like Audio Note, but they charge a small fortune for them.

Kondo, Allnic, Airtight, Audio note (uk), WAVAC, all make great sounding tube amps, but they are not necessarily better than vintage models (even the older models of these companies will favorably compare with current manufacture).  I am particularly enamored with modern tube amps from the Italian company Synthesis.  But, my absolute favorites remain quite old Western Electric amps and a custom built OTL from the early 1990s.

When people say that today's amplifiers are better, or vice versa, have they really heard a broad enough sampling of both to make that claim?  Have they really heard the best of vintage amplifiers--such as Western Electric 59A (252 pushpull), 91A (300B single-ended), 86 (pushpull 300B), Marantz 9, etc.?  I heard a demonstration where a very good current model Audio Note Kageki (parallel single-ended 2a3) was compared to the 59A playing Audio Note AN-E speakers.  The Kageki sounded wonderful until the 59A stepped into its place--the comparison was so startling that it made the Kageki sound like it was broken.  The Kageki is now almost a six figure amp and it does not come close to the 59A playing speakers that should be friendly to Audio Note amps.  I really like the sound of the Kageki (I own a pair), but the 59A is so much better--more vivid and alive, more rich and harmonically saturated, and still relaxed sounding (not edgy).  The 59A probably costs twice as much as the Kageki these days, but for someone who can afford it (not me), it would be the end-game amp.

I like the 45 tube tube too.  Are you using it single-ended with 94 db/w speakers?  That would be a bit on the edge.  I had a pushpull 45 amp which I used with 99 db/w speakers, and I had no issues with power, except for large choral works at somewhat high volume, but I did sense that I was at the edge.

I don't know what kind of caps are in the power supply, but, I can check on it as the dealer still has it.  I would guess paper in oil type, as this is commonly found in Western Electric gear.  My re-built amp uses such caps. 

I am waiting on the same dealer finding the appropriate value of Western Electric paper in oil caps for my speaker.