Individual Outputs for the Korg KR-55

With the uniPulse installed you are able to trigger each of the Korg  KR-55’s instruments individually via midi. Here we will show you how to add individual outputs that are scaled to line level.

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As we look into the schematic of the KR-55 we can see that the volume of each instrument is controlled with a potentiometer. These potentiometes are important because here we can pickup each instrument individually. We do that by installing a voltage divider parallel to the potentiometer. The voltage divider will help us to scale the signal’s amplitude to line level (Peak to Peak ~ 1V) and at the same time the output impedance is reduced.

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.Because the instruments have different output amplitudes each one needs an individual voltage divider for scaling:

  1. Bass Drum
    R1=100k R2=10k
  2. Snare Drum
    R1=75k R2=16k
  3. Cymbal
    here the voltage divider is not needed (R1=0 R2=inf)
  4. Hi-Hat
    R1=47k R2=47k
  5. Tom Tom,  Conga
    R1=82k R2=10k
  6. Rim Shot, Cowbell, Claves
    R1=75k R2=16k

Note that for the best result for the cymbal output you have to turn the cymbal potentiometer to the lowes possible volume. Otherwise other instruments are mixed into the output. All other outputs are fine and dont have this “bug”.

We soldered the voltage dividers directly to the potentiometers and placed the 3.5mm jacks at the side of the KR-55’s chassis.

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2 thoughts on “Individual Outputs for the Korg KR-55

  1. this is great – thanks! I was just thinking about how to do this. However i was wondering why it is necessary to use a voltage divider to compensate for the potentiometer – why not simply bypass the potentiometer – and use the mixing buss to adjust volumes before it goes to it’s individual track or tracks during recording?

  2. The voltage dividers reduce the level to a line compatible level. If your mixing desk can handle the high level directly, you can of course use it without the dividers.

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