high power tube amps vs ss

HEY. you 6550 guys, you need SYLVANIA 6550's not those shrill GE's.
I use Winged C's myself as the last quad I saw of unused Sylvania's was going for $600 and that was a few years back.

If I could make transistors do what I can do with ease with tubes I would make transistor amps.

But I can't and no-one else seems to be able to do so either, although a very few (less than 5) come close.

That thing that tubes do is they don't make odd ordered harmonic distortion the way that transistors do. Most solid state devices have a non-linear capacitive aspect that is inherent in the junctions of the device. This capacitance is multiplied by the amount of current through the device. This is one reason transistors make more odd ordered harmonic distortion than tubes.

The discussion about guitar amps does have relevance here. Guitar players prefer the smoother (lower odd ordered harmonic distortion) sound of tubes, especially when overdriving (clipping) the amplifier.

Because tubes (triodes in particular) are the most linear form of amplification known, it is possible and practical to built a tube amp with no negative feedback that has fairly low distortion. This is really hard to do with transistors, and it is notable that the best transistor amps made (in my book) are all zero-feedback designs. However, 99% or so of transistor amps use feedback, and feedback actually *increases* the odd-ordered harmonic distortion in any circuit.

Since the ear uses odd ordered harmonics to figure out how loud a sound is, by adding trace amounts to the signal the result will be brighter and harsher.

The bottom line is if you want it to sound real instead of just a really good hifi, you have to find a way to get rid of that negative feedback. Usually that means going to tubes, and then finding a speaker that works. BTW:

High efficiency speakers would make life a lot easier, but I thought those type of speakers sounded shrill and thin. It may be because I have only heard them with ss amps.

The last sentence here is the important bit.

My speakers are 98 db 1 watt/1 meter, and go to 20Hz. I can shake the building with a 60 watt amp, without concern of clipping the amp. Most 'high power' systems I hear cannot play with the volume, the impact or the clarity I hear at home. Even at +100 db sound pressures, it still sounds smooth and relaxed. IME most audiophiles won't listen at levels over 90db because their system is too harsh. Real music plays at +100 db levels, if you can't do that at home without discomfort, something is wrong with the system.

GE / SYLVANIA? Last I checked they were pretty similar, if not identical. Unreliability of this tube vintage keeps me looking to new stuff. I do like my 12 AX7 Amperex Bugle Boys and Sylvania and Tung Sol 6 SN 7 tubes, but they are more plentiful. Jallen

Ralph, I tried your experiment of ramping up the gain. I was playing an EMI CD of Tchaikovsky (sp?) Nutcracker. The dynamic range is between 20 and 30 db. I never made it beyond 95db. At that point, external distortion made me turn the gain down. I'm referring to wifey. She threatened to throw a bucket of water on my gear. She introduced at least 90db of negative feedback and the odd ordered harmonics from her screaming really hurt my ears. Any suggestions?

I've owned a LOT of tube guitar amps and a couple of SS and hybrids...tube amps are simply snappier and make people happier. I do use SS bass amps though, as you need extreme power for that. Same with tube hifi amps...60 watts per side with 90db speakers and a SS sub (so sue me) shake my walls if need be, so I bet this sort of thing would shake yours. Also regarding heat...with only 4 KT120s there is not too much more heat than a recent partly class A SS amp I was using, but the tube heat is expected...a Twin Reverb will make the beer on top of it sweat all over the place...just a warning.