DJB-013 Quantizer and Lag Module |
I often use my sub-octave divider to create sequences and wanted to be able to quantize the outputs. I had not yet built the Blacet MiniWave nor the PSIM, both of which provide this function. I also wanted a lag circuit so I combined them both in this design.
I started with an Arp-style quantizer that I found on Chris List's CV Quantizer page. I enhanced this design with a better clock oscillator and I wanted to use a parallel counter instead of a ripple counter. The sample and hold operated better with an improved sample pulse so I improved the reference detect pulse generation circuit. I added some input hysteresis and an offset adjustment so that 0 volts would quantize to 0 volts.
For the lag circuit I wanted both a linear and exponential lag but the time constant sounded quite different (as it should). I wanted the alternate shape to have about the same time sound so I adjust the timing capacitor with the mode selection. I am using 1M linear potentiometers and I really should use log but have been unable to find them in other than carbon.
I used a 'shortened' MOTM-000 prototype board for this module.
DJB-013 FrontPanelExpress design file