How do tube Watts compare to SS Watts?


I have Theil 2.2 speakers, which have a low sensitivity (86dB), but I would like to get an intergrated tube amp. Or even all tube. But I don't know how many tube Watts I'll need to drive the Theils. My guesstimate is @ 50wpc for intergrated tube amps, but that could be wildly off. Are their mathematical conversion formulas? Second, if there is a rough range, might you be kind enough to suggest a few worthy candidates that, wheather new or pre-listened, are under $1,000 USD (e.g., Cayin model xxx). Thank you most kindly.
rascal52240
Rascal52240, a Watt is a Watt is a Watt. It is a measurement. An inch on a ruler is the same as an inch on a tape measure. That said, Watts needs to be considered as part of an equation. Your Thiel's 22's have a nominal impedance of 4 Ohms and a minimum impedance of 3 Ohms. Better ss amps may double their power into that load. In your case as a matter of measurement ss Watts may be 2X more powerfull than tube amps with the same standard 8 Ohm rating. Thiel designs their cross-overs in such a manner so as to provide a steady impedance for the amp, which helps maintain steady amplitude. Some argue that, these steps drain the ultimate apparent power from the system. The point of all this is; Thiel's respond best to lots of quality power. Of course, your room and ultimate sound levels will determine just how much power you need. For many years I used the same ss c-j amp you are currently using on earlier Thiel's CS 2's. Those 2's had an easier 6 Ohm nominal, 5 Ohm minimum load. A move to a much better 250 watt amp demonstrated qualities I never new my CS 2's were capable of. Jim Thiel told me himslelf that his power recommendations were based on the standard 8 Ohm rating of quality ss amps that were capable of doubling down, and if one were to choose tube amps, one should double those power recommendations. Comparable tube power usually costs more than the same ss power. Doubling that tube power can get a bit expensive. With a budget of $1K, I'd suggest you use ss watts. Furthermore, very few integrateds have the guts to really make Thiels sing, it usually takes a dedicated power amp to get the most from Thiel's, especially when you get away from the smaller 2 ways. An old audiophile cliche' that some how seems to work more often than it should, suggests that one should double the manufactures' minimum recommendation. For your Thiel 22's that would mean 200 watts into 4 Ohms. A quality 200 watt per channel tube amp might be hard to find for under $1K. To drive your Thiels, that money may be better spent on better ss watts.
Smooth explanation, thanks. This explains why the KT88 and KT90 have different characterits in voicing. And as you know every KT90 amp will have different circuitry/ quality trans, and that also every model KT90 tube will possess somewhat different characteristic. So tubes can be a big wide open field, whereas ss amps, is "what you see is what you get" Not much can be done for a ss amp. Its all "hard wires". Great tubes can offer that much more . Tube amps with a hefty trans, can be considered an ss amp with the added benifits of musicality of tubes.
btw where do the 6550's fit in. I have a DEFY 7 sitting waiting for a preamp. Very interesting looking tube. Shorter than the KT90 but wider. Very unique looking tube. I know I will prefer it over the JOR's KT90's. The 6550 may be one of the best tubes for classiacl/orchestra. I'm betting on it. The KT90 can be a bit "raw"/"steely"/"cold", but definetly has some slam and a full midrange/good bass. The highs roll a bit. I'm guessing the 6550 kicks in more high fq's, with a "softer bass" I'll post a review whenever I get a pre, maybe next month.
>>whereas ss amps, is "what you see is what you get" Not much can be done for a ss amp. Its all "hard wires"<<

I think Nelson Pass, Hervé Delétraz, Charles Hansen, etc. etc. have proven that is quite untrue.

Thank you.
rascal, listen well to unsound advice. he has firsthand knowledge and based on my exp with jolida 60 wpc and$$$ he is right on the mark. a watt is a watt basically. thiels need POWER! an old tube amp is no more powerful than a new used tube amp. shop around awhile if you can but 60 wpc in a tube is not more than 60 watts from ss even if the ss has a rolled off clipping circuit like NAD offers. unsound has spoken with thiel himself and is really doing you a great service. 60 wpc may sound good but 100 is going to make them sound as good as they should. fwiw, in your $$$ range the sonic differences between tube amps is not as imp. as wpc in the case of driving low eff. speakers. ;)
Bartokfan, the assumptions you make pertaining to the characteristics of tube are incorrect. There are a great deal of variance is sound characteristics of any given tube from different manufacturers. A Tungsol 6550 sound very different to an Electra Harmonic 6550, which in turn sound different to SED, Svetlana or Phillips 6550s.

Additionally, factors such as the circuit design, quality of components, screen grid bias method etc. etc. have dramatic effect on the sound.

EL34 are generally known to be very melodic when run in triode mode, yet partnered with the right speakers they produces a prodigious bass slam in my V12i. KT88’s are known to have bass slam, but they are wonderfully melodic and detailed in my Audionote.

Observations on what a amplifier/tube sounds like, should be made after auditioning, not before.

Regards
Paul