The OPL3 module originally has three TL074 op-amps, and a circuit that needs +/-12V bipolar power supply.

In Wilba and nILS sammichFM, they use two OPA4348 rail-to-rail op-amps, that can be powered by 5V.

Sauraen suggested another 5V rail-to rail op-amp, the MCP6004, which is pin compatible with the TL074, and a way to modify the OPL3 module to use these.

- Replace R5,R7,R10 and R13 with jumpers - Bridge IC6 pads 1&3, 5&7, 8&10 and 12&14 - Leave out:

IC6, 
R4, R6, R8, R9, R11, R12, R14, R15
C15, C16, C19, C20, C23-C30 

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