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Power output of tube amps compared to solid states

I'm having a hard time trying to figure out how tube amp power output relates to solid state power output. I've been looking at the classifieds for tube amps and I see lots of tube amps with 50w or 60w output, but nothing close to the 250w output typical of solid state amps.

So I have no idea what type of tube amp is required for my set up, right now I'm using totem forests with a required power rating of 150w-200w at 8ohms. The bass is so powerful on these that I have the sub crossover set to 40hz.

My question is, are tube amps so efficient that 50w from a tube sounds like 150w from a solid state? Or will 50w output from a tube severely limit how loud I can play my speakers? If so, are tubes usually meant to be driving super-high efficiency speakers?

I had previously tried a tube pre-amp with a solid state power amp (both musical fidelity) and didn't like the results because the imaging suffered greatly, even though the music sounded nicer from a distance. Now I want to try a solid state pre-amp (bryston) with a tube power amp (no idea which brand to look at), but I don't know how much power output I need or if it will even be possible with my speakers. Does anyone know what I would require?
acrossley

Showing 19 responses by pubul57

pubul57
3,712 posts
 
I remember hear a 30 watt tube amp "versus" a 250 watt SS amp at a Stereophile show, simply to see if people coult tell which was playing in an A/B demo. I don't think the speakers were particularly high efficiency, but the difference in power was not in the least bit noticeable at fairly loud show room conditions - and yes, it was fairly easy to pick the tube amp.
pubul57
3,712 posts
 
Unsound, I think you hit on it, some speakers simply need SS to be driven properly ans tube amps will not perform well with them - usually amps with low nominal input impedance, but perhaps more importantly speakers with big swings in impedance at various frequencies - I think Theil speakers might be like that. Like the question of passive versus active preamplification, the system context makes all the difference, and not necessarily the inherent attribute of the amp, preamp, or anything else.
pubul57
3,712 posts
 
Wow. Now this is good reading.
pubul57
3,712 posts
 
I have to believe science plays a role here, there is still good design and bad design and I believe is governed by understanding electrical principles. If that is not sound, no pun intended, you are not going to get good equipment. Now as to the seasoning that a knowing chef wishes to use, that is more subjective, and the art in audio engineering IMHO.
pubul57
3,712 posts
 
Duke, Ralph, Unsound, thank you for the dialogue - very interesting indeed.
pubul57
3,712 posts
 
I thought Ralph's point was that the choice might be because of the differences in the way tube and SS introduce different types and levels of distortion, not power per se. I do know this about power, I seem to want as little of it as possible, as long as it can make my speakers as loud, fast, and dynamic as I need them to be.
pubul57
3,712 posts
 
How does this discussion apply to tubes versus SS in preamps?
pubul57
3,712 posts
 
Doesn't the signal have to fight through all that copper wire? To me there is no doubt that tubes sound better, so maybe Bill Johnson's explanation is true, yet it does seem that a signal has a long way to go from needle or laser to drivers.
pubul57
3,712 posts
 
Well, for whatever reason, tube amps sound better to me, and believe me I have tried several times to fall in love with an SS amp (all have been Class A)and they always end up going back and I go back to my tube amps. My speakers may have a lot to do with that, I'm sure with some SS would be the way I would have to go and tubes might not do quite so well in driving them.
pubul57
3,712 posts
 
Is there such a thing? Seems like SS can drive anything, it just won't sound as good as tubes with speakers that can be driven effectively by tubes.
pubul57
3,712 posts
 
What are the virtues of a DC-Coupled amplifier like the Atma-sphere?
pubul57
3,712 posts
 
Speaking of damping, don't drivers in speakers have their own damping where some drivers need more damping and others less, so that they don't need, or want, to much damping from an amp. For instance, my Merlins are said to have critically damped (whatever that means) damping and therefore work best with tubes and tended in the past to not do so well with SS as they overdamped the speaker.
pubul57
3,712 posts
 
THaks Shadorne, that explasins what Bobby was talking about, with which he then says, which is why it works so well with tube amps, Atma-sphere among the best with my speakers.
pubul57
3,712 posts
 
Duke, which of your speaker designs is best for a room 11x18?
pubul57
3,712 posts
 
Makes sense. We'll talk.
pubul57
3,712 posts
 
Are "poorly" designed speakers by your definition, poor engineering, or an intentional tradeoff with gains in other areas?
pubul57
3,712 posts
 
Do tubes have the same "advantage" in preamplifiers?
pubul57
3,712 posts
 
Always thought the Acoustats were designed around the "current" paradigm. I would be surprised if the M60s would do it, Zeros or not. Always seemed like SS was the way to go with that speaker, but....
pubul57
3,712 posts
 
No doubt the M60s are quality watts:)
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