Drip edge Princeton Reverb cabinet buzz.

[galtjunk]

I have a 67 Princeton Reverb.
I am getting a buzzing from the cabinet on low notes.
It doesn't happen when I use an external cabinet.
I changed the speaker and tested it before I mounted on the baffle and it didn't buzz.
I mounted it on the baffle and the buzz came back.
The screws holding the baffle board are tight.
The screws holding the chassis are tight.
What else should I look at?

[Stevem]

Push some plastic Tacks thru the grill cloth far enough to hold it to the face of the baffle board in 4 locations and see if you still get the buzz.

If you do have you removed the chassis to check if it's that?

[galtjunk]

I held and moved my hand over the grille cloth while it was being played but it didn't change.
I will try the pins later today.
I will also remove the chassis and check it,
Does the drip edge attach over the grille cloth and is it removable?
Is the baffle held in with the 4 screws on the back?

Thanks

[xtian]

I chase these issues using a sine wave generator. Dial in a frequency and amplitude that causes the rattle. Then you have both hands free to explore the chassis, cabinet, hardware, etc, to find the noise.

[ChopSauce]

+1 with xtian

...
What else should I look at?

Cables, maybe?

Anything not properly held close to a surface, more generally...

[TUBEDUDE]

Loose batten, crack in baffle.