Soundstage powered 12" home subwoofer

[imaddicted2u]

My Son sent me these pics. Capacitor blowed up...any thoughts on what the value might be?
Not much left of it to identify but he says the can is same size as 220mfd 25V caps on the board. Safe bet to try to replace with one of that size?
There is no model number on the box.

[spiros.p]

Re: Soundstage powered 12" home subwoofer

probably yes look at the traces on nearest cap if is together with the blowed cap.and for sure you have to replace all capacitors.and maybe is more damage do to exploded cap check all components around.

[eccerr0r]

Re: Soundstage powered 12" home subwoofer

This is not a typical cap failure mode. Usually something catastrophic happened like way too high voltage or reverse polarity... Have to trace circuit unless you knew one of these happened due to putting a cap in wrong or using a cap that's too low voltage for the circuit?

[imaddicted2u]

Re: Soundstage powered 12" home subwoofer

Thanks for replies.
I wish I could have the amp in front of me to trace the circuit but it's thousands of miles away.

My son went and got a few 220mfd 25v caps and before I could get him to measure any voltages he put one in and it started smoking as soon as plugged in.
There are 2 power supplies +/- 60v.
These are dropped to +/-15v supplies are the power feed for the other audio processor circuit board.
The -15v power measures good. There is a 220mfd cap in the same position in the -15v circuit. So I figure that both circuits likely duplicate each other and the 220mfd is likely the right one.
With the blown cap removed there is 60v across its contacts. This is a 25v cap so no wonder the smoke is getting out. The + on this cap is on the +15v power.
Looking at the pics he sent me I noticed a 330mfd on the other board that is bulging. It happens to be connected to the other end of the +15v on the ribbon cable. So it would make sense that all caps, on both boards, that have been subjected to 60v should be replaced. I had him disconnect the +15v from the ribbon cable so we can concentrate on fixing the +15v power. Just hard to do without a schematic and trying to trace it out from pics.
Who knows what may be damaged on the other board and will it blow up again when the +15v is fixed and reconnected...

[eccerr0r]

Re: Soundstage powered 12" home subwoofer

so the regulator went open circuit and this second "new" cap was about to go nuclear?

Indeed 60v on a 25v cap = rapid self disassembly seen here - just wanted to mention 30V on a 25v would just get bulging, probably a pop, and smoke.

As usual good photographs are good. Some of us have gotten good at photograph reverse engineering (not me...) but it goes a long way. cleaning the dead cap guts (and clearly marking the position) would be helpful.