more reverb damper

I was going to have the reverb damper control panel located two plywood layers deep, but this would have necessitated cutting a nicely-shaped oval hole in the original baffle to line up with the oval in the new baffle.  This would have been difficult since the old baffle is not removeable, so given the protruding edges of the cabinet sides, it wouldn't be possible to get my power jigsaw in there to do the cut.  I would've had to use some kind of small hand scroll saw, which I don't have so first I'd have to go tool shopping...  And anyway, I didn't really like the knob being that far back inside a "tunnel" of plywood layers.  So I realized, I could just cut out a larger square-side notch in the old baffle, as seen, and then mount the panel at the level of the back of the new baffle, so going through an oval hole in only one layer of plywood.  Looks better, and easier to implement.



As you can see here, the reverb base mounts with the control panel protruding through the square cut in the old baffle, ending up against the back face of the new baffle.


I'm glad I made the control panel extend farther forward than any other parts of the reverb base.  I wasn't planning on mounting it like this, but the result is fortuitous.


Cutting the oval opening in the speaker baffle for the reverb damping control, necessitated painting the baffle again.  I don't mind, it needed another coat anyway.  Since the diamond grille is permanently epoxied into place, I had to carefully mask it before painting (if I knew I was putting in this reverb damper, I would've done the painting before affixing the grille, but this is what happens when we invent and redesign as we go!).





 

Placing the felt.

The reverb tank will have felt isolation pads on the screws that attach it to the plywood base.  This will (maybe) have acoustic benefits, and also will lift the tank up just a bit, to give more clearance for the damper control wire which passes underneath; otherwise the wire would rub against the tank when it was rotated, which would make an audible noise in the reverb.

The felt which accomplishes the actual damper effect is two layers, folded over the control wire.  The back edges are superglued together, and also to the wire.  The portion which touches the springs is the folded edge, with no glue.  Hopefully this does the job; it won't be possible to test it for quite a while.





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