Sir Kingsholto . . . .
I can see that thar unit 'taint bein' no K-mart $99 Blue light special.
What you have yourself there is the final filtering portions of a class D digital power amp, and those 6 black FERRITE encased cylindrical inductors to the side, plus your involved capacitor sets, are responsible for taking the received high power and high frequency digital pulses and filtering them to conform to . . . . and then be a power analog signal again, to feed to your speakers.
It takes a capacitor that can up to STRONG pulse signals, to be used in this application.
Did any "ghost" lettering remain on the side of the case of the ruptured unit to compare to the lettering of the other like / identical units . ? ? ? To confirm . . . if that was being an ORIGINAL installed capacitor ?
Under the consideration that possibly . . . . a Pratley Peterhead . . . .Mr Fixit extraordinaire . . . might have used a conventional capacitor in a repair attempt . . . . and this would be the expected result.
I have NEVER seen such a drastic, color transition from an all familiar ORANGE to a COAL BLACK casing colorization.
Caps
0.1 ufd at 250V
0.47 ufd at 400V (those are the ones that really get the hell hammered out of themselves)
See how the burn up / or carbonification around the power surface mount resistor responds to clean up with the scrubbing bristles of an acid brush . . .or old toothbrush + Q tips and an aggressive solvent like lacquer thinner or acetone or MEK . That should then let you see if there is any board proper carbonation, which would have to be dug out if approaching a ground planes proximity.
73's de Edd
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