Voltage Controlled Chips

SSM 2044I’ve been chatting to Tom Wiltshire from Electric Druid.net about Voltage Controlled Chips.

Back in the good old days you could by a chip that would do the various sub parts of a synthesiser, for example the SSM2044 is a complete voltage controlled low pass filter (used in many classic analogue synths).  Tom has developed a voltage controlled envelope generator and voltage controlled LFO. This got me to thinking about a couple of ideas I’ve had in my head for many years now.

Firstly,  A complete moog ladder on a DIL format chip. The idea was to use surface mount components and create a DIL module that enabled people to buildsynths using this as a simple building block.

Secondly, a DIL module holding a voltage controlled wavetable oscillator. It’s no secret I’m a fan of PPGs (check PPG.synth.net for more details) and I’ve always wanted to build a polyphonic wavetable synth. The Monowave was a step towards this, but the size of the voiceboard would’ve made a polysynth absolutely enormous and also contained 1000′s of components, far more than I’d have been willing to solder.

With Tom’s achievements fresh in my mind, it’s brought this whole concept back. Tom has put a lot of work into these two chips, he’s even written comprehensive datasheets for each, nice work Tom!

I’m going to have a dabble with the idea of the VCDWO (Voltage Controlled Digital Wavetable Oscillator) over the next few weeks to get back into the flow of building hardware and writing embedded code. I plane to use an Atmel Mega32 for the prototype (as I have half a dozen not being used currently) and I’ll post updates here as things move on. Once that’s done I’ll be more confident about getting back into the flow of development and build for finishing Defender.

One Response to “Voltage Controlled Chips”

  1. John Moore Says:

    Nice idea Paul. With available CEMs and SSMs stocks dwindling I’m sure others would be interested in a new set of basic building blocks.