I apologize for the jaw-wag, but I noticed something strange today and would appreciate some feedback: I stumbled on the pedal tone skill today, and after playing around with certain low-low pitches (between C and A mostly. I checked with a tuner), I noticed that my vocal chords started to beat, as if they were in sympathetic resonance a few cents away from the pedal tone feeding back from the mouthpiece. This happened with more intensity when I was playing with better timbre and confidence. I'm positive that I was not unintentionaly making the vocalizations through the normal means (speaking, singing...). First off, is this in any way common? It was a bit disconcerting feeling my vocal cords vibrating without my intention, although the pedal tones felt good on my tired lips. Now, a few hours later, I feel a slight soreness in the pipes like a singer would feel after a long practice session. Is it possible to cause excessive strain on the vocals by playing pedal tones, (or any tones for that matter) on the trumpet? Something just dawned on me while previewing this post. I thought the endpoints of the trumpet were at the bell and the mouthpiece, but now I suspect that they are perhaps at the bell and the diaphragm. Does an arbitrary pitch played on a particular instrument resonate more freely in a certain part of that instrument?