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OB-6 Expression Filter Trick

OB-6 Expression Filter Trick
« on: May 21, 2017, 02:31:23 PM »
So, as you know, the OB-6, like the P6, has an expression pedal jack on the rear for controlling the cutoff frequency. This is a great feature, and works very well with an expression pedal. But I've also found another way to interface with it. I'm sure there are several, but I've tested this one, and it works very well, so I thought I'd share it. You'll need a Korg SQ-1.

  • Connect a 1/8" to 1/4" TS cable to the CV-A Out of the Korg SQ-1 and the Expression Filter on the PB-6.
  • Set the SQ-1 A and B sequencer settings to 1V/Oct, Linear.
  • Set the SQ-1 initially to run sequentially through both A and B.
  • Set the Mode initially to SLIDE.
  • Turn on each step, and adjust each step's knob so that they run gradually from full counter-clock wise, to clockwise.
  • Set the rate to taste.
  • Now select a patch on the OB-6, start playing (or run the sequencer on the OB-6), and start the sequencer on the SQ-1.
  • The SQ-1 should essentially operate as an LFO at this point, gradually, and smoothly changing the filter cutoff value over time.
  • Play around with the SQ-1 rate.


Once you get that working, try the following:
  • Change the mode to GATE ON/OFF
  • Change the sequence to RANDOM
  • Turn up the rate fairly high.
  • With these settings, the SQ-1 will behave sort of like a S&H.


Have fun!