Major Questions Concerning Tube Amps..??


I have read quite a bite about tube amps, positive as well as negative. Here are my questions. I have heard that the distortion level with tube amps are high, is this true.?? Tube amps are usually rated very low in terms of wattage, does this mean they provide more current that solid state amps and if so wouldn't that shorten the life of the tubes. If I replaced the amp that I have for my mains with a tube amp, will this drastically affect the sound of my HT being that the rears and surrounds are powered by a solid state amp.??

DMH
dmhaney

Yes, occasionally, distortion is higher with tube amps, but the character of the distortion is more pleasant.
I know it sounds hokey, but you won't worry about the "specs" once you've heard a good tube amp.

Tube amps come in all wattages, however, 50w of tube amp power "seems" like 100w or more of SS power.
I don't know the science behind this, I'm sure it's here if you search.

Current can vary among tube amps, some do run through tubes faster than others, some may be biased by the listened with tube life vs. sound in mind.

If you listen to music more than HT, I would definately recommend at least 2 channels of tube power. 3 (Left Front, Center, Right Front) channels would be great.

It is my understanding that most info still comes from the center speaker and teh front 2. All of the speakers won't sound the same with tube and SS mixed, but even with identical speakers and identical amps, the positioning of teh speakers will result in a difference in sound. Bottom line- you're curious, and that's good. Once you listen to a good tube amp, You won't go back to SS!

I'd suggest an amp that uses 6550, or kt88 tubes, as opposed to el34. El34 tubes have a richer midrange, but a hardcore solid state guy would immediately miss the bass that most el34 based amps lack.

Anyway, good luck!!!
Most of what Gthirteen says is right on the money.
However, I think you'd be fine with leaving center channel ss and just going tubes for front l+r. Most center channel sound is spoken dialogue, vs. music and sound effects out of the mains. I've read plenty of folks here using that combo w/o problems.
Your concern about current/tube life is not really the right way to think about it. Yes, some designs will have longer tube life than others, but it's a function of the entire circuit design and parts choice, not just a function of a current spec that you should base your decision on.
Trust your ears, and don't worry so much about the power ratings. If you tell folks what speakers you are driving, many will be able to offer their experiences driving them with both ss & tubes, and help you figure out what tube amps to consider. Then go listen to as many as you can, with some music that you know well. Cheers,
Spencer
DMH,

The wattage is the product of the voltage and the current -
so if the amp, for a given voltage is delivering less wattage,
it is delivering less current - not more.

The above posters are correct that although the tube amp puts
out more distortion - it is a more "pleasing" distortion.

Tube amps put out mainly "even-order" distortion products -
while solid state amps put out mainly "odd-order" distortion
products. Our hearing is more "bothered" by the odd-order
distortion than an equivalent amount of even-order distortion.

Unless you're an electical engineer, and really understand
the specs and all their implications - ignore the specs and
trust your ears.

Dr. Gregory Greenman
Physicist