I know i'm getting a little hiss (which i admit is white noise- noise from wide range of frequencies) from the distortion, which comes out of the head phones, and causes postive feedback loop (this is the proper term, when you say feed back to guitarist they see Hendrix or Sonic youth and what they did, and that sounds different).

"and buliding up whatever resonance the amp has. Adjusting the master volume 'tunes' the amplifier resonance to a lower pitch"

sorry i dont follow that. Why should it tune to the natural resonating frequency?Shouldn't it just get louder?(as you've got a constant driving frequency, and there's no real reason for it to change).

My orginal question was getting sound out of an amp THIS way (perticularly THIS sound), and you said yes. Which you could have said first time with out sounding condesending (back to your "can you say feedback" remark).