ALM Sid Guts Puts C64 Sound Into A Eurorack Module

alm-sid-guts-moduleALM has introduced the Sid Guts – a new Eurorack module basd on the sound generator chip used in the Commodore 64.

The MOS Technology 6581/8580 ‘Sound Interface Device’ chip, aka the ‘SID’, was the sound generator chip used in the Commodore 64 home computer. The SID, by the means of 3 wavetable oscillators, a real analogue multi mode filter, an ADSR and various cross modulation options, provided the soundtrack to a generation of computer gaming.

The Sid Guts takes the legendary SID chip and tailors it into the Eurorack modular environment. By use of a real SID chip, the classic sound is taken in a new direction with the levels of direct and voltage control only a modular system can offer.

Here’s a video introduction to the Sid Guts:


  • 1volt per octave control of a ‘core’ SID oscillator 0-5v input (with tunable offset)
  • Direct and voltage control of oscillator wave shape selection (Pulse, Triangle, Square, Saw).
  • Filter switchable between 4 modes – 12dB/Octave HP , LP , BP & Notch (HP+LP).
  • Direct and Voltage control (with offset) of Filter cutoff and Resonance.
  • 1 volt per octave control of second SID ‘modulation’ oscillator.
  • Direct and voltage control of modulation oscillator ‘type’; ring modulation, sync or none.
  • Direct and voltage control of pulse wave pulse width.
  • External audio input.

The SID GUTS does not support the following SID features;

  • Remaining 3rd oscillator
  • ADSR
  • Other features include;

See the ALM site for additional details and sound demos.

via Oliver Chesler

7 thoughts on “ALM Sid Guts Puts C64 Sound Into A Eurorack Module

  1. Very nice design – its practically impossible to build a synth that takes advantage of *all* the SID’s features (for example the PCM playback “glitch”) and still keep it user-friendly. This looks and sounds like a great trade off. I’ve got a couple of raw chips around and got them up and running with an arduino, but programming the registers is extremely finicky. Sounds great when they work, though! Any idea of the cost, and can we provide our own SID’s (which are very much out of production)?

    1. I think you *have* to provide your own sid! from muffwiggler: “There is an initial factory built run of just 50 modules available in next few weeks. THESE DO NOT INCLUDE A SID CHIP, SIDs must be user supplied !!! SIDs are easily inserted on the rear of the module. Expect retail pricing on these 50 to be around 300 GBP each. “

    2. There seem to be new reproduction SID chips that are cheap. I recently bought a mos6581 off eBay from a Thailand company and plopped it into my Elektron SidStation. Sounds and performs the same as the original C64 chip that came with the unit. It cost ~$20 IIRC.

  2. In the words and voice of Big Daddy Kane “RAW”! I want two of these and one of the Arduino based modules that lets you load samples with a SD card. Forgot the name.

  3. The MIdiBOX SID already does a great job at getting a whole lot out of the SID chip! 300 quid is a bit of steep price, but I gues that’s what they need to charge due to the very limited amount produced. I’ll wait for a DIY kit version, which should be coming too 🙂

  4. just an FYI for all the SID lovers out there….if you have an old commodore 64 you can buy a cartridge called cynthcart that turns it into a 3 note polyphonic analog synthesizer!!!

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