Leslie Amp Maintenance

The following was anonymously added to LeslieAmplifierModifications. I've moved it here. (Take it with a grain of salt. If components in your amp have drifted way out of spec, of course that's a problem; but I don't think that everyone agrees that Leslie amps need to be extremely precisely balanced.) --JeffDairiki

    Here's a couple tips for optimizing your leslie 122 amp.

    # Use a matched driver tube. The driver tube is the 12AU7 nearest the volume knob.
      TorresEngineering is a good source for all of the parts I'll mention.
      ~?Also see PartsSources -ed.

    # Carefully match C9 and C10,the  .01 600v  coupling caps in between the aforementioned driver tube and the output tubes.
      Here's a link to a site with schematics  http://hammondb3andleslietips.com.
      Orange drops sound good here.

    # Also match resistors R5 and R7, 1 MEG 1/2 watt.
      Ohmite carbon comp are a good choice, just buy (and measure) 10 or 20 and you'll get a good match

    These changes provide a much more equal signal to both sides of your output tube.
    You'll hear the difference in volume, maybe a huge difference if your original components are very uneven.