Have you ever had a guitar that was buzzing/rattling, and just couldn't find it? I've had 2 or 3 acoustics across my bench where I just couldn't figure it out. Not string buzzing, but a vibration coming from the body. I can't find any loose braces... pulled all the electronics and wiring... one had a loose bridge; I removed and reglued it. Still there. Not the ball ends. Tightened all the hardware. Adjusted the truss rod. I've been through Mr. Ford's fantastic list, but nothing is checking out. Am I missing anything obvious? Or will I continue to be haunted by the sound, much like Poe's Tell Tale Heart?
Loose bolt on a bolt on neck? I've encountered this a few times
Good thought, but no... the latest is a standard joint. Although, I did once have a Martin brought in with high action. It was a newer one with a bolt on neck... except there was no bolt. The threaded insert was there, and the sticker appeared undisturbed. But no bolt.
The ones that almost got me were:
Vintage style Martin with the old school press in tuner bushings with a washer - a miniscule gap between the ferrule and the washer was allowing the washer to resonate at certain frequencies and was most noticeable.
Maton AP series UST has a cable stay which screws to the pickup body inside the guitar - this has a washer on the screw and when it comes loose it goes off - loudly - as it is in direct contact with the piezo holder. Note: not on all AP pickups.
Straplock end left clipped to strap pin.
Taylor truss rods - new necks supplied by Taylor immediately without any fuss - fixed the problem, may the gods bless the bolt-ons for ease of change out.
Floyd rose saddles "zinging" when they get old - just change them out and the problems go away.
Franks big buzz book is great: however it's almost an invitation for guitars to find new ways to defeat the methodical application of this great tome.
I'm aware you've stated the rattle is coming from the body but you also mentioned adjusting the truss. I would maybe add "knocking" the neck to see if perhaps it's loose within the channel route. Lots of other possibilities already mentioned.
I believe it was in Jose Ramirez III book "Things About the Guitar" when he mentions having to chase down an unknown buzz. It was driving him mad, much like your rattle is I suppose. I believed the culprit turned out to be the chair he was sitting in, in Mr. Ramirez' case. This is only to describe that a number of things completely unexpected can cause a rattle...even your chair!
Best of luck in your search,
Well, after finding and gluing up a very tight crack in the back, and re-running all the cables to make sure nothing touches the top or back. I also ended up adding foam tape between the preamp and body, and the battery compartment as well. It seems to have done the trick. I was just glad to get it off the bench. On to the next problem! Sorry, opportunity!