1958 Bassman
Filter Cap Replacement:
Original Capacitors:
Darn near new looking. Don't be fooled. Inside those old caps is a time bomb waiting to happen. Especially since this particular amp was not used for more than nine years.
Replacement:
I was extremely careful with this example. These amps are very valuable. I removed the original cap, and wound the new cap lead along the same route as the original.
Caps in:
Notice how the new Sprague Atom capacitors are a lot smaller than the original Astrons. Technology has come a long way. BUT, these caps need to be in there solid.
The Solution:
Since this is an extremely valuable amplifier, I did not want to do anything that would in any way detract from that. I used silicone on the right two capacitors to hold them together. I made sure the silicone did NOT touch anything but the caps. I then used one-sided Hi-Temp adhesive foam cut to size to fill in the gaps. I stuck the foam to the caps NOT the pan. Everything can be removed with no knowledge of it being there.
Finished:
I topped the caps with the foam so there would be just enough to have a snug fit when the pan was screwed back on. Again, I stuck the foam to the caps, and not the pan or amplifier. I also kept the pan elevated while servicing as not to strain or damage the original wires.
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