Why do Tube Amps sound more romantic v SS amps

@keeferdog

My last three sets of Speakers have been Sonus Faber. I was a long time user of solid state amps. They are really good (in general) at detail and slam. Well designed tubed amps frequently capture the warmth and natural beauty of music… the human voice for sure. Since I finally switched to tubed amps. I’ll not be switching back.

Quite by process of evolving my system I converged on Sonus Faber, Audio Research components and Transparent. This, it turns out to be a known synergistic combination.

@invalid "with simple designs fewer parts count” which leads to higher distortion, shorter “relatively good performance" lifespan, and higher maintenance cost, in order to bring tube amp back to spec. SS amps aging at much slower (x100) pace then tube, pl admit it.

I don't know where you get your tube amps from, there are tube amps from decades ago still running strong. Once solid state amp give up they take out circuit boards sometimes and you can't get those boards anymore because they are proprietary. Tube amps can be point to point wired and can be fixed at anytime in the future.

@atmasphere "an imbalance in power tubes will cause a 2nd harmonic, not a third"

not really, AB imbalance does contribute directly into third (odd) order harmonic increase. Perfectly balanced second (even) only order harmonics distortion, AB designs “distort" A and B the same way only if tubes are perfectly matched, which NEVER happened. it is very hard to pick matched tube replacement, which will age at the same pace to the <1% point.

Good designed SS amps have many AB transistors in parallel, which reduces imbalance problems. SS amps I have all are “maintenance free”, and there is no need to change any transistors due to aging degradation in 100 000 hrs life time.

I just purchased a Bryston 2.5 cubed amp (for small 14’ x 12’ x 8’ room) I can’t quite wrap my head around this amp. For example, I have two or three go-to female vocalist tracks (one is- Sam Brown’s solo on PF’s live (“The Great Gig in the Sky”) that literally gives me goosebumps or makes the hair on my arms stand up every time I play it, with the tube amp. I’ve yet to experience the “hair on my arms stand-up” playing this track on the Bryston ss amp?

@keeferdog 

In your case, the simple answer is the tube amp is sounding more real.

not really, AB imbalance does contribute directly into third (odd) order harmonic increase. Perfectly balanced second (even) only order harmonics distortion, AB designs “distort" A and B the same way only if tubes are perfectly matched, which NEVER happened. it is very hard to pick matched tube replacement, which will age at the same pace to the <1% point.

Good designed SS amps have many AB transistors in parallel, which reduces imbalance problems. SS amps I have all are “maintenance free”, and there is no need to change any transistors due to aging degradation in 100 000 hrs life time.

@westcoastaudiophile 

We’ll have to agree to disagree since my experience is different from yours! FWIW transistors rarely match at that well, often being quite a bit further apart than tubes. But they are a lot cheaper so you can afford to go through a few to find a decent enough match, a hidden cost in case anyone is wondering why high end solid state amps might cost more than their mid-fi brethren.

Our tube amps parallel of a lot of output devices as well, since they are lower power tubes and a lot are needed to drive speakers directly without a an output transformer. So we have the same advantage of the differences ironing out in the wash as you suggest happens in the output section of a traditional A or AB solid state amp. As these tubes age they tend to drift towards a common value; if tested a few months down the road they tend to test extremely close to each other! As a result (and also because of how the bias is controlled by a very low impedance circuit) the Bias and DC offset of the OTL is thus quite stable and not prone to drift. That kind of stability is part of why we’ve been able to stay in business nearly 50 years.

You may not get 100,000 hours on the equipment before corrosion has had a chance to damage the semiconductors, depending on how long it takes to log that much time. So there may well be a need to replace a device well before that. Just FWIW.