Description

Videos above demonstrate the original Mutable Instruments version of the open source Rings. The CCTV clone is functionally identical.

Immutable Rings is a clone of Mutable Instruments’ best-selling open source voltage-controlled resonator.

Immutable Rings brings physical modelling synthesis to your Eurorack system. Instead of trying to be a complete instrument, it focuses on the key ingredient, the resonator, ready to be excited by envelope clicks, trigger pulses, granular noise or any other audio source produced by the rest of your system.

Three families of vibrating structures are simulated by the module, with CV control over their parameters:

• Strings, membranes and tubes as modelled by Mutable instruments Elements’ resonator section (modal synthesis).
• Strings coupled together and vibrating in sympathy, with controllable intervals between them.
• Strings with a variable amount of inharmonicity.
• Immutable Rings can be configured so that each new note is played on its own virtual string, while the previously played note(s) still decay. This unique take on polyphony allows the module to play strummed chords.

Controls

• Number of strings/structures (1, 2 or 4).
• Synthesis model (modal, sympathetic strings, string).
• Main frequency (quantised in semitones).
• Structure. With the modal and string models, controls the inharmonicity of the spectrum (which directly impacts the perceived “material”).
• With the sympathetic strings model, controls the intervals between strings.
• Brightness. Specifies the brightness and richness of the spectrum.
• Damping. Controls the damping rate of the sound, from 100ms to 10s.
• Position. Specifies at which point the structure is excited.

Specs:

• Input impedances: 100k.
• AD/DA: 16-bit, 48kHz.
• Internal processing: 32-bit floating point.
• Open-source hardware and firmware.
• Easy firmware updates through an audio interface.
• Cortex-M4 ARM processor.
• Width: 14HP
• Power consumption: +12V: 110mA ; -12V: 5mA.

SMD is all preassembled, leaving only the through-hole parts to assemble – pots, jacks, LEDs, and buttons. The firmware has been pre-flashed.
Estimated time to solder is about 1 hr

Immutable Rings – Build Document | User Manual (linked is Mutable Instruments’ full open source manual and project files. CCTV’s version of Rings is identical in terms of control layout and functionality)