Originally Posted by Kimeran
Thanks for that Arny.
What I would really like to see though is Amp A and B hooked up to the same speaker driven by the same front ends with their frequency response measured with the different equipment.
Modern audio measurement gear is accurate enough that you often get pretty much the same response curve even if you use different measuring equipment.
I remember that someone loaned me a set of B&K measurement mics that had a street price of about $1500 each. I also had a number of Behringer ECM 8000 measurement mics ($40) and a few Panasonic omni mic capsules ($2). I taped them together mechanically aligned and did a FR measurement of a very good little speaker. All of the response curves fell within the calibration curve of the B&K's from 30-18K.
However, I did notice right away about how the tube stuff and SS stuff measure quite differently in those links you provided.
The frequency response of tubed amps is more likely to be affected by the impedance curve of the speakers you use with it.
I will say that I am someone who likes tube gear. I am sure some of it is a "ooooh, it glows!" romance but I seem to like the sound of tubes...hence the reason I think distortion and what kind of load it can handle are more important than total watts an amp has.
If you want low distortion and the best load handling, modern SS amps are so much better than almost all tubed equipment that there is really no comparision. I grew up with tubes and when good SS equipment became available it was like "Don't let the door hit you in the butt when you leave" for me with tubes.
If you want warm sound like tubes, add some noise, crank the mid bass for warmth, and maybe throw in a little hum. If you want to go all the way, put 1-4 ohm power resistors in series with your speaker wires. ;-)