Submodular Synthesizer

The ISHIZENO ONE is a submodular synthesizer. It decouples faceplate from electronics in order to provide more modularity. It is built around an iPod Touch used as touchscreen, configuration interface, and advanced processing unit. It provides 8 monophonic channels. Each channel is supported by a modular 16-pin breakout board. Patching between the faceplate's controls and the channel's breakout board is supported by a set of analog crosspoint switches configured through the iPod Touch.

Each monophonic channel provides:

• 8 analog ports
• 2 concentric knobs
• 2 small knobs

Any analog port or knob of any channel can be patched to any pin of the channel's breakout board. Patching can be done through the multi-touch user interface, or through a QR code printed on the breakout board and scanned by the iPod Touch's front-facing camera. Patches can also be downloaded from the Internet through the iPod Touch's WiFi connection.

The module includes two AD7606 8-channel 24-bit analog to digital converters. This allows the built-in iPod Touch to be used as a low-frequency 16-channel oscilloscope. By default, the osccilloscope's channels are patched to the input and output of every monophonic channel.

Out of the box, the module does not provide any synthesis capabilities. Instead, these are added through breakout boards, with up to 8 boards (one per channel). The module also includes an Arduino Uno used as middleware. Programming can be done through the Arduino, through the iOS operating system of the iPod Touch, or both. Obviously, the Arduino and the iPod Touch can be used as software sequencers (among many other applications). The analog crosspoint switches can also be reconfigured dynamically in order to support high-frequency dynamic patching.

Dynamic patching is enabled by a matrix of 32 AD75019 analog crosspoint switches. These switches have no gain and a low 150 Ω resistance. No more than two switches are ever used in cascade, thereby limiting the overall resistance to 300 Ω.

All knobs are connected to a set of four AD5254 digital potentiometers with 256-position resolution and providing a resistance range of 1 kΩ, 10 kΩ, 50 kΩ, or 100 kΩ. This setup allows all 32 potentiometers to be controlled manually through knobs, digitally through Arduino or iOS, or modularly through traditional voltage control.

Patching across channels can be done through the faceplate's 64 3.5mm jack chassis sockets or through the analog crosspoint switches. Using crosspoint patching, any of the 8 analog ports and 4 potentiometers of any channel can be patched to any of the 6 analog inputs of the Arduino Uno, and any of 8 shared analog endpoints.

The faceplate also include two spinner control knobs and two USB ports, one connected to the iPod Touch's lightning connector, and one connected to the Arduino Uno. The USB ports can be used to connect controllers like keyboards or grids.

This module is at the early prototyping stage. Specifications will vary.

All software will be released under an open source license and all hardware designs will be released under a Creative Common license.

Feedback welcome.

https://ishizeno.wordpress.com/

• ? mA +12V
• ? mA -12V
• ? mA 5V

No info about availability.