How do tube Watts compare to SS Watts?

The reason you hear a lot about tube watts being more effective somehow is due to distortion- tubes make less of the distortions that the human ear finds objectionable- and so *seem* to have a greater percentage of usable power relative to transistors.

The effect is real enough on account of the way our ears work, but if you measure sound pressure levels for the most part watts is watts.

A lot also has to do with the load, in particular tubes in general behave differently from transistors, i.e. they do not double power as impedance decreases. Often though they may *increase* power as impedance increases. Sometimes this gives you more punch on certain box speakers that have a low frequency resonance.

Bottom line is that there are a lot of variables but with many speakers you do get the impression that tube power carries more 'weight'.

>>Bartok says ....SET amps with 300B, 845 are low power, "no slam" "no authority"<<

That is sheer profundity. It's a combination of the speaker and amp, not totally dependent on the amp. I've heard plenty of SET amp/speaker combination with "slam" and "authority". Conversely, I've heard speakers that would make your amp melt down like Chernobyl.

Your statement is totally incorrect. Learn the subject matter before making such disingenuous and sweeping statements.

Thank you.

03-14-07: Eldartford "The sound level that can be produced by a tiny amount of power"

Now that I can agree with ... :-)

after rereading above posts... i'm going further on the limb. fwiw, i think you are gonna 'need' more than 60 wpc of tubes to get 'er done. honestly i think thiels work best with lotsa juice. ss gets it done of course but you want to delve into tubes and being a convert myself i encourage others. never owned thiels but have auditioned them and they can sound kinda listless, yet defined, w/o enuf power. if you could hook them up to tubes and audition i think you would not need any of this contradictory advice. good luck! fwiw, 86 db design is a stretch in $1K 50wpc arena. personally i'd want 100wpc but your listening tastes are unknown to me

I stand corrected. What i mean to say is that on most speakers, SET amps, 300, 845's will not provide the current necessary to produce tension, "slam". I've had KT88's in my JOR and the result was total failure. The amp lost all its "authority". So I also place KT88's in "SET" category, even on a push/pull design. I have not heard the Cayin KT88 yet, that might change my opinion. Point is, some tubes in many designs do not offer the body in MOST speakers that a decent ss amp will offer. Put any SET amp with a Vandersteen and then put a decent ss amp. SET's will not drive the speaker. Tubes can make great music, that is IF you can find the right speaker. As you point out its a combination of the 2. Much easier done with any ss amp, tubes work only with certain speakers.
Please correct if/where I err.