XO106r5: Quad square-wave drone module with patchable logic and filter (22HP)
5 in stock.
The XO106r5 is a logical progression from its predecessors - although it no longer contains any 40106 ICs, it's still a good source of square-wave glitchiness along with a filter should you want to round off some of the rough edges.
It's also a lot bigger - 22HP.
The salient features are:
- 4 AVR-based square-wave oscillators with V/oct response good for around 5 octaves. There are fine-tune pots on the back side of the PCB.
- Voltage-controlled pulse width for each oscillator
- Oscillator firmware is available under a permissive license.
Patchable Sallen-Key low-pass filter - use it, or don't; it's something of a nod to the previous incarnations of the module (note that this is not a VCF - if you want that sort of thing, you can easily patch to an external filter module)
- Patchable logic matrix - this is the big step from the previous versions. The oscillators are no longer hardwired to the logic IC; you can patch things together how you want, or not at all. The logic IC itself is socketed so you can replace it with a different, pin-compatible, IC should you wish to change the voicing of the module. The 'default' option is a CD4070 (quad XOR) but alternatives include the 4001, 4011 and 4093.
THE DEFAULT CONFIGURATION FOR THIS WILL BE A PCB/PANEL/FIRMWARE SET - I don't recommend this is as a beginners project.
The BOM and schematic can be found here
The terminally curious can view Johnny Beaver's demo of a prototype unit in action on YouTube ... 'production' units will have my usual purple/ENIG FR4 panels.