Added AMP Balance trimmer to VCA#27
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May 13, 2026
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- In some VCAs we experienced that the output is slightly shifted from 0V. This PR adds a balance trimmer to the amplification of the long-tail pair so that it's possible to fine tune the 0V point.
- In some VCAs we experienced that the output is slightly shifted from 0V. This PR adds a balance trimmer to the amplification of the long-tail pair so that it's possible to fine tune the 0V point.
- In the first opamp stage of the Output (U5A), the opamp side was essentially floating. When there was a DC on the + node of C14 then that DC appeared on the - side too but had nowhere to discharge so essentially DC wasn't blocked properly. Inserting a 100k resistor to ground turns the input into a high pass filter with a cutoff frequence about 0.15Hz which discharges the DC component of the input. This is essential in the output stage of the synth.
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