If ch4 is working on mix out, the final summing transistor is ok. I bet, the ch4 individual out jack has a problem. And if the chs 1-3 appear on their individual outs, you are lucky because it's only a matter of cut wires. May be the former owner tried to eliminate crosstalk or "sing through" by cutting or desoldering the wires, who knows. Yours Michael [Non-text portions of this message have been removed]
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Re: [Simmons Drums] SDS-3 and the outputs
2010-12-06 by Michael Buchner