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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
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atmasphere's avatar
atmasphere
12,111 posts
 
Mapman, that is as succinct an explanation as I have ever heard. Well done.
unsound
7,344 posts
 
Mapman, Atmasphere, not everyone take offense to the same things.
mapman's avatar
mapman
22,788 posts
 
Unsound,

That is true.

I suppose that could be one reason perhaps why many are tube fans yet many are not.
atmasphere's avatar
atmasphere
12,111 posts
 
Unsound, what is meant by offense is not really a matter of taste. Back in the 1960s, GE did a test where they played music and test tones for people and gauged the response.

What they did was to introduce two types of distortion- even lower orders, and higher odd orders, in two tests. What they found was that people will tolerate without objection up to about 30% distortion if its all lower orders, but tiny amounts of odd orders, less than 0.1% was highly objectionable!

IOW, what they found out was that the human ear listens for the 5th, 7th and 9th harmonics in order to determine the volume of a sound and that we are sensitive to distortions as low as 0.001%, where we really don't care about lower orders (the 2nd,3rd and 4th).

This is also the difference between tubes and transistors as far as distortion goes. I myself do not like what many have come to call the 'tube coloration' and I have found that with careful design there is no reason to have to tolerate it either. Nor do I like transistor coloration, but its a lot harder to design transistor amps that lack it; all of them that I have heard that lack transistor coloration are all also zero feedback class A designs, I think not out of coincidence.

I don't fault anyone for disdaining the typical distortions that are easily heard in a lot of gear- I feel the same way.
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