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Herb and Stone Liquid Foam

Herb and Stone Liquid Foam  ·  Source: Herb and Stone

Gianluca Herbertson of Herb and Stones was demonstrating his Liquid Foam dual sequencing groovebox on the Hainbach Superbooth stream. It’s available built or as a PCB and Panel DIY kit.

Liquid Foam

The heart of this compact groove machine is a pair of sequencers that you can patch into the synthesizer in quite complex ways. The patching is done with banana-type patch cables like those found on Buchla synthesizers and each sequencer has 4 patch points which make for some interesting explorations.

The analogue VCO has two stages of waveshaping, a decay-only envelope generator that can be inverted on any step, a 2-pole resonant low-pass filter and a CMOS-based final overdrive stage.

The sequencer creates pitch via an unusual method of digital-to-analogue conversion called a resistor-to-resistor ladder using a 5v gate signal that’s converted to a stepped waveform that goes to the VCO. The sequencers are capable of all sorts of inter-patching.

It looks like a lot of fun and the sound coming out is really engaging and melodic especially when using more than one. Gianluca has been asked about doing Eurorack version and it’s definitely something he’s considering at the moment.

Other products in development include a similarly shaped machine that’s a dual-mono or stereo multimode filter with its own sequencer and complex LFO, and a “drummer friend” for the Liquid Foam which sounds really interesting. He’s also got an analogue VGA filter with CV control for video effects coming out soon.

Liquid Foam is available for €320.

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2 responses to “Herbs and Stones Liquid Foam: modular monophonic analog groovebox”

  1. Paul Boos says:

    That looks fun!

    I couldn’t make out, did you see any information on whether it can be driven by an external clock? Or send a clock out?

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