Sunday 16 August 2020

Ampeg SS-140c Channel A Pre Amp


  1. Now verified. Similar to VH140C but less drastic/effective tone controls. But this one fits in a small box...

    1. do you have a demo of it? and is this meant to go in front of an amp like the master effecfs stuff or is it an actual preamp that i could run straight into a power amp?

  2. I see something strange in the schematic. The last stage, the one where is R18, is not a gain stage, so it doesn't matter the value of R18, it won't boost the volume, I think.
    I'd say, to boost the signal, the schematic needs at least a resistor from IC2 pin 6 to the ground, and in this case also decrease that 10nF in parallel with R18 to avoid treble cut.