I think I'm the only tuba player on ASR, at least that admits to it
But I don't think I've said what you said. I've said that tuba notes are routinely recorded down to frequencies in the 20's, even though tubas themselves don't produce a lot of fundamental at those frequencies (the sound is dominated by higher harmonics). I've also said that I don't want harmonic distortion at those frequencies, because it makes tubas sound like euphoniums (which are pitched an octave higher). I've also said that the bass Moog licks on Rick Wakeman's
King Arthur and the Knights of the Round Table are a better test of bass response in my systems than any of my (many) tuba recordings. That Moog can deliver sine waves down in the 20-40 Hz range with a great deal more power than can a tuba. But it still has to have enough harmonic distortion to sound clear, which a 30 Hz sine wave by itself will not.
Yes, my current main-system amp is capable of delivering over 300wpc continuous, and I do appreciate how well it delivers that bass end of the Moog.
I suspect my amp uses that power much more fulsomely delivering percussive transients than any sustained bass note. At least, that's what the clipping indicators tell me.
Even so, I think it's reasonable to ignore claims of momentary headroom and purchase amps based on continuous output. That should be easy to do, given how much power is available for a reasonable cost these days. My amp that gives me that 300wpc continuous cost about $700.
Rick "16 Hz is a double-pedal C on a tuba, created by most performers using flutter tongue, and required in only one work" Denney