Tube amp power watts equivalent to Solid State?


I have a Cayin 35 watts tube amp. What is its equivalent to a solid state amp?
50jess
C'mon guys, everybody is entitled to getting started on this hobby at some point. And we all know there are a number of confusing aspects of it.

50jess, I'm certainly no specialist, but here's one explanation in layman terms.
1 Watt is 1 Watt...equals to 1 Amp x 1 Volt, or any combination of AxV equating 1 W. Hence the above sarcasm. However, there is no established standard for how this is measured by the various manufacturers, and then some amps work at relatively low voltage delivering high current, and others vice versa. And some speakers need high current while others don't. It all depends on the design, and on how the manufacturer decides to rate the amp at any given power.

So high current amps conservatively rated power-wise are often said to equate to more powerfull amps. Conservatively here is used as a term relative to most amps in the market.

There is not really an answer for your question. Maybe a better way to think about it would be in the context of the speakers you have or you are thinking about having. Generally speaking, you would be looking at higher efficiency speakers, probably at 91 dB/W sensitivity at minimum for a 35W tube amp. But then again, it's not only the sensitivity that matters, but the shape of the impedance as a function of frequency...probably this sounds too complex, but at the end of the day you either want to know what speakers are a good match to your amp, or what amps are a good match for your speakers...and can disregard the reasons if you don't care to get into that mumbo jumbo.

I hope this helps
My 12wpc SET monoblocks (845 output tubes, EL-34 drivers) designed and built by a friend sounded much more authoritative and powerful than the CJ Premier 12 monoblocks (140 wpc) I used to have.

So, for me, this contention -- tube watts delivering something more than SS watts -- must have SOME validity. It may not make sense, but I heard it, at length, playing all kinds of music, in my own system. Ten years later I'm still astonished at the twelve-watters. And my speakers are not of the ultra-sensitive variety.

Fortunately I'm not an engineer or I'd know this couldn't happen :-)
"03-16-14: Dopogue
My 12wpc SET monoblocks (845 output tubes, EL-34 drivers) designed and built by a friend sounded much more authoritative and powerful than the CJ Premier 12 monoblocks (140 wpc) I used to have.

So, for me, this contention -- tube watts delivering something more than SS watts -- must have SOME validity. It may not make sense, but I heard it, at length, playing all kinds of music, in my own system. Ten years later I'm still astonished at the twelve-watters. And my speakers are not of the ultra-sensitive variety.

Fortunately I'm not an engineer or I'd know this couldn't happen :-)
Dopogue (Threads | Answers | This Thread)"

In your case, there may be a different explanation for your results with the SET's. In many cases, low power triode amps increase image size. Images of vocals and instruments just get bigger. Its easy to mistake that for more power.
03-16-14: Dopogue
My 12wpc SET monoblocks (845 output tubes, EL-34 drivers) designed and built by a friend sounded much more authoritative and powerful than the CJ Premier 12 monoblocks (140 wpc) I used to have.

So, for me, this contention -- tube watts delivering something more than SS watts -- must have SOME validity. It may not make sense, but I heard it, at length, playing all kinds of music, in my own system. Ten years later I'm still astonished at the twelve-watters. And my speakers are not of the ultra-sensitive variety.

Fortunately I'm not an engineer or I'd know this couldn't happen :-)
Not necessarily :-)

In addition to ZD's point, what stands a very good chance of having been a major factor, as alluded to by Lewinski and Unsound, is the amplifier's interaction with the impedance vs. frequency characteristics of the speaker.

Many speakers have impedances which rise to extremely high values (e.g., 40 or 50 ohms) at some frequencies in the deep bass region, and also to values of perhaps 20 or 30 ohms in the vicinity of mid-range crossover points. For a given input voltage, the power delivery of a solid-state amp relative to its power delivery into 8 ohms will decrease in direct proportion to that impedance rise, when the amplifier is operated within its maximum power capabilities. Its maximum power capabilities into those high impedances will also decrease dramatically, relative to its 8 ohm rating. Both of those effects will occur to a much smaller degree in the case of a SET amp, and many other tube amps.

It should be clarified, btw, that the CJ Premier 12 is a tube amp. However, it has an output impedance (measured by John Atkinson as 0.87 ohms at mid and low frequencies) that is much closer to being in the solid state camp than in the camp of nearly all SET's and the majority of other tube amps. Everything else being equal, that will cause the Premier 12's interaction with speaker impedance vs. frequency variations to be more solid state-like than that of most other tube amps.

Also, nobody has yet mentioned that the characteristics of the distortion rise that occurs with tube amps as their power output approaches and somewhat exceeds their rated maximum capabilities tend to be less offensive than in the case of solid state amps, i.e., they clip more softly. That can contribute to a tube amp being seemingly more powerful than its rating would suggest.

Also, see this thread, which includes extensive discussion of related issues by some very knowledgeable folks.

Regards,
-- Al