Herbs and Stones Liquid Foam Synthesizer
Liquid Foom is a monophonic analog groovebox that revolves around a dual sequencer designed to encourage complex pattern exploration.
It can generate anything from straightforward 4/4 loops to ever-changing byzantine synth lines, off-key tantrums and organic percussive phrases.
At the core there’s an analog VCO with two stages of waveshaping, a decay-only EG that can be inverted any step, a 2-pole resonant low pass VCF and a CMOS-based final overdrive stage.
Liquid Foam can sync with virtually any other machine via its clock input mini jack and it sends a 5v clock out/through pulse for further syncing and chaining.
Includes 5x 30cm banana cables and a universal 9V power supply.
- Clock
The speed of the sequence is set by the rate knob. the upward arrow indicates the
clock input jack, the downward one indicates the clock output jack.
When an external clock is detected at the clock input jack the internal timing instantly
synchronizes to the external one. If the external clock stops or the jack is
pulled off the internal clock will start to drive the sequence again after a couple of
seconds. - VCO Pitch
Inputs A, B, and C will take gate signals from the sequencer or the lfo and create 7
different pitches according to the relation between them. pitch knob sets the
master pitch and when turned completely counterclockwise it will silence the oscillator.
From low to high pitch the gate combinations are: A, B, AB, C, AC, BC, ABC. - LFO
The LFO outputs a rectangle wave and its pulsewidth can be manually adjusted
with the width knob, apart from the obvious rate knob there’s a led indicator and a
jack output. The LFO output is normalled to sequencer B input. - Sequencer A
Sequencer A consists of four outputs and in its basic state just one of them can be
high on any given clock step. The LEDs gives visual feedback of the clockwise rota.
tion of the active gate.
If a gate signal is applied to input X and/or Y the rotating pattern will change its
course and different combinations of high gates will be available, thus permitting
the creation of more complex patterns and melodies . - Sequencer B
Sequencer B is tied to the relation between the clock speed and the LFO rate and
width: every clock step it checks the LFO state and if it is high then it will pass
a gate through its four outputs, in a similar fashion to sequencer A but rotating
counter-clockwise. This means that by controlling the LFO parameters the four
gates can be all low, all high or anything in between. - Envelope Generator
The decay-only envelope generator is triggered every time a gate signal is patched
to the ABC inputs, the lenght of the envelope is controlled by turning the
decay knob . If a gate signal is present at the eg inv input the curve of the
envelope gets inverted and the offset knob sets how much the inverted signal will
affect the filter cutoff frequency. This means that the same sequence can have
different envelope slopes on different steps.
Whenever a gate signal is patched to the eg➔vco input, the envelope generator is
routed to the VCO frequency input, bypassing the A, B, C signals. This may be
pretty handy to make kick drums or, when combined with the inverted envelope,
portamento/glide effects between different notes. - Wave Mixer
The VCO can output and mix together three different waveforms: triangle,
sawtooth and rectangle wave with variable pulsewidth .
There are two wave blending and shaping stages: when turned clockwise the first
wave knob blends between triangle and sawtooth while the second one blends
between whatever waveform is present at the first stage (tri, saw or anything in
between) and the rectangle wave which pulsewidth is set by turning the width knob. - Low-Pass Filter
The two-pole 12dB/oct low pass filter is affected by the envelope generator and the
freq and res knobs. - Drive Stage
CMOS-based overdrive stage just before your 1/4″ jack output, warm sounding,
when completely turned clockwise the output signal will get pretty hot.
