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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
trelja
3,223 posts
 
Arthur, thank you for the insight, I appreciate it. There's a lot to think about there.

I believe the transmission analogy is a good one. Even if for me, accepting the inherent performance superiority of dual clutch transmission, nothing can replace the joy a clutch pedal provides. I'm also glad you touched on Black Body Radiation.

One point of contention is that Class A is not the exclusive condition of the single ended topology. And, conversely, push pull does not need to be Class A/B or Class B; plenty of PP amps operate in Class A.
paulfolbrecht
603 posts
 
Arther, I quite enjoyed your post as well (and previous) but was also a bit confused as to which of your comments apply to SE topology and which to class A bias. Seems to me it was actually mostly the former.
atmasphere's avatar
atmasphere
11,807 posts
 
Br3098, they can be excellent help if the load impedance is too low!
aball
2,016 posts
 
Oh yes, sorry for the confusion, Paul is right. I had SE Class A in mind. That's the type of amp I've been on the prowl for so that's what I've been thinking about lately.

My comments still apply for Class A push-pull however because they have the same ungapped core design as Class B push-pull since the two halves of each channel remain in opposite polarity and similarly sum in the secondaries. Hence my generalization from the circuit design point-of-view.

Arthur
orpheus10
8,668 posts
 
There is a scientific explanation as to why Class-A amps sound better than Class-B,but there is no scientific explanation as to why tube sounds as loud as solid state when the tube is less powerful.
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