So here's the scoop. I put a new speaker in my '66 Deluxe Reverb. Upon tightening everything up, I've got a rattle that is audible THROUGH THE SPEAKER when I crank it and play the lower strings. It sounds different than the amp drive, and stops about a third of the way into the sustain of the chord/note I'm playing. Here's what I've tried so far: -Amp into different speaker cabinet with known good speakers. Still get the rattle through the speakers in this cabinet. -Taking off pre-amp tube covers. Rattle still there. -Holding power tubes/rectifier tubes. Still there. It didn't start until after the speaker change. Any suggestions as to where to try next? I can't just live with it, as I track with the amp on a regular basis. Thanks!