I’ve recently redesigned this project and have made a bunch of changes to the circuit. Here is the most current schematic as of December 7 2011. Click the image below to enlarge.
The schematic above is a substantial improvement over the other schematics below which I used in the past. I’m leaving them up for those out there who have used them and need them for reference. Other than that I strongly advise that you use the schematic above. It may be overly complex for your application but I tried to compartmentalize the schematic into its discreet parts so that it can be remixed as needed.
This project is similar to the cam shaft sequencer minus all of the moving parts.
I’m still working on getting all of the circuitry right.
There’s a sample at the bottom of the page that I made using the sequencer to control a casio SK1,an analog bass drum synth and an analog noise synth.
There’s also a casper built echo circuit in there.
Here are some pictures of the first prototype.
The sequencer is made up of four rows of 10 switches.
There are four different sequences that can be programmed using the switches in that row.
The left most column is an on/off switch for each row. The right column switches between “short” and “long” mode for each row. In “short” mode, the sequencer creates one 50% duty cycle pulse per step. In “long” mode the sequencer outputs a 100% duty cycle pulse per step. So it will string two or more pulses next to each other into one long pulse the image below should clarify.
Here’s an awesome schematic of a programmable, rhythmic mixer sent in by SUBBS. Click the the image below to see a larger version.