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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 10 responses by mapman

mapman's avatar
mapman
21,838 posts
 
Power output I believe, regardless of amp technology used, translates essentially only to how loud things should go, all other factors aside.

This does not say anything about how optimally an amp drives a particular speaker design. By optimally I mean that all frequencies are delivered essentially on equal ground even as the load impedance varies by frequency from the nominal, generalized overall rating.

Distortion will be lower when an amp drives a speaker with higher input impedance in general I believe, all other factors aside.

In general SS amps are better able to drive speakers with lower input impedance more optimally and with lower distortion for properly balanced sound than tube amps (in general).

That is my general understanding. Please correct me if I am off base here.

My point is that power output alone ma determine the quantity of sound (volume/spl) that can be produced, but not the quality, even at lower volumes. Other factors come into play there.
mapman's avatar
mapman
21,838 posts
 
Atmasphere.

No further clarification needed on my behalf. Transients are key. Its pretty clear to me that its mostly about details relating to distortion and how different factors contribute to that, as you say.
mapman's avatar
mapman
21,838 posts
 
My understanding from the experts is not that tubes are more powerful, rather they distort in a less offensive way that makes them able to go louder before the listener takes offense.
mapman's avatar
mapman
21,838 posts
 
Unsound,

That is true.

I suppose that could be one reason perhaps why many are tube fans yet many are not.
mapman's avatar
mapman
21,838 posts
 

' 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."

That's a very good way to look at it !

"The last thing I want to say is that we must also be on guard to not fall into the trap of trying to explain why some folks choose tube amplification as simply a matter of power. Power is but one piece in the puzzle."

Good point. And probably not even the most critical one, at least in the simplistic terms usually applied to describe it which typically do not determine that your speakers are as loud fast and dynamic as they can or you need them to be.
mapman's avatar
mapman
21,838 posts
 
Atmasphere,

What speakers cannot be driven by SS and why?

Thanks!
mapman's avatar
mapman
21,838 posts
 
Atmasphere,

Interesting.

Does Wilson then state that the Watt/Puppy was designed to work best with tube amps, or is that just the way it happened to turn out.

If not, then it sounds more like the Wilson design is flawed however a tube amp might be the right bandage.
mapman's avatar
mapman
21,838 posts
 
It seems there is no single model or paradigm that can account for all possible combos of amp and speakers that work well together. Usually, two things work well together because they were designed to do so. So it all boils down more to the desires of the designer and how well that matches to those of the listener. There are certain engineering principles that can guide this process to a happy conclusion, however in the end no two designers or listeners are likely to share the exact same goals, which is why the search for a single absolute truth in audio is a fruitless one.
mapman's avatar
mapman
21,838 posts
 
Two different recipes that both can produce some very good soup.

Atmasphere's is a more unique recipe I'd say that might deliver some very special results if followed properly.
mapman's avatar
mapman
21,838 posts
 
"Do tubes have the same "advantage" in preamplifiers?"

That's a good question! For many like me with tube-unfriendly speakers, the pre-amp (and source perhaps) are the practical places to introduce tubes.

I love my ARC sp16 tube pre-amp, but I do wonder if a good SS pre-amp could also deliver for similar cost or less once the speaker/amp optimization has been achieved.
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