pretty Thunderbird related topic so....
careful with marketing hype and
placebo effect in using the wrong part for the job. The minimum voltage rating Sprague/Cornell Dubilier "Orange Drop" caps is about 100Volts. Way overkill when passive bass signals are in the order of .2Volts, further, in conventional T-Bird wiring, the output signal of the bass never passes through this capacitor where a higher quality polyester or polypropylene dielectric could potentially make a difference (never in reality due to the low passive bass signal level), instead it's used to attenuate higher frequencies by shunting them to ground. As mentioned (in another post), these caps are meant for active high voltage circuits such as those in VT amps where they truly shine, some are rated to 1.5kVolt, hence their higher cost..
Wiring (mine) of my BaCH with ThunderBucker 66 N/Bs where I used a 47nFd ceramic disk rated at 50Volt just because it sounded right...
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Wiring of my '13 with '76 Sidewinders...I left the stock little (in physical size) blue ceramic which I confirmed is a 22nFd....one of my best sounding basses..
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Stock wiring of my '68 with a 27nFd ceramic disc rated at 50Volts....no lack of warmth here...
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