Tube Amps Watts vs SS amp

I too have heard the claim that tube watts are subjectively more powerful than solid state watts, and I have sort of felt that way myself.  I actually think that good tube amps, coupled with appropriate speakers, sound much more lively and engaging than solid state amps playing at the same volume; you have to crank a solid state rig up to a higher volume to get the same sense of liveliness, hence, the impression that tube amps sound more powerful than their rating. 

The actual numbers would suggest otherwise.  The published tube amp output is typically where the tube is actually distorting quite a bit, and a more comparable wattage rating to where solid state is rated would actually be MUCH lower.  Arguably, a tube watt is less than a solid state watt, but the subjective impression is quite the opposite.

The AR 9 is somewhat of a beast to drive (87 db/w @ 4 ohm nominal impedance).  While it is possible to use a small tube amp successfully, it would mean accepting modest sound levels, a smaller room, etc.  I think solid state is more likely to be the best choice, but, you never know unless you audition some tube gear in your system.

Yeah- measures worse, sounds better. That's pretty much it in a nutshell.

With larger power supply, tube amplifiers tend to play louder than SS with same watt spec.

20 years ago I had Jadis 500(350Watt) which played louder than Krell KSA 150(350Watts at 4 ohm).

Rogue Cronus Magnum II (kt120 100Watt) play much louder than most 100 watt SS amp.

Thomas

I find it interesting that so many audiophiles, particularly those who favor high-powered amps, measure quality by how loud an amp will play.  For me, the measure is just the opposite--how soft can an amp play and still deliver satisfying sound.

Tube W sound more powerful than SS W because tubes distort more and higher distortion will be perceived as higher loudness even if the measured SPL is the same.