• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

re-stuffing cans need help with polarity

Hi, I'm restuffing the cans for a sherwood S-5000ii. I'm on the last can, the other 3 were all (-) terminal gound to the metal can. The 4th one is worded differently and I think it means that the (+) terminals are wired to ground. It say on the can bottom line "-COM POS". I'll include the schematic and a pic of the can. The capacity is "C4" on the schematic. I'm pretty sure I have it right but I want verification before I solder it all in. Thanks.


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Not all electrolytics are filters to ground (where the higher potential is at the component and the chassis is considered 'zero' volts). Some are involved in bias circuits where the chassis is deemed '0v'...so to get 'minus' voltages we have to be grading from a greater to a lower potential at the component.
So...connect your caps to the cans as indicated in the circuit....whether '+ve' to can or '-ve' to can...the can if well attached will represent chassis potential.

You are...though I also prefer the original look of cans...better off changing to a pcb or other board using external components...it's just so much easier to service them...and I guess maybe you could have a thinnish s/s rectangular cover made to go over it.. start a craze