Harmonics before the filter.
A biased mixer stage adds even harmonics before the ladder shapes them, with an output stage that keeps the drive range useful.
01 Software instruments. Circuit by circuit.
The character lives in the circuit.
Voltage Synths is a family of software synthesizers built around the electrical behaviour that gives an instrument its identity: oscillator interaction, filter topology, envelope timing, drive, glide and the small differences between voices.
Roles, circuits and developmentExplore the instruments
Methods, measurements, limitsSee the evidence
- Original instruments and circuit-based studies
- Musical behaviour tied to physical relationships
- Repeatable analogue variation and reliable recall
Instrument panelSubstance
02 The first instrument
Starting with one voice.
Substance concentrates the Voltage method into one playable monophonic voice: a direct signal path, deliberate drive and the articulation needed for basses and leads.
Two oscillators, a sub-oscillator and noise feed a driven mixer, then a pole-mixed four-pole transistor ladder. The filter moves between low-pass, band-pass and high-pass at two slopes, while a dedicated drive path travels from clean weight to dense harmonic colour.
Playability is part of the model. An eight-note held stack returns to the previous note without a gap, and constant-rate glide makes larger intervals take longer. Eleven starting patches move from deep subs and dirty basses to plucks and singing leads.
Resonance that respects the bass.
Compensation inside the ladder helps a resonant bass keep its fundamental instead of turning thin.
Glide and note memory belong to the voice.
Held-note fallback stays legato, while interval and direction shape the glide journey.
03 The first four instruments
Two series. Four musical purposes.
The foundation series grows one direct voice from mono into polyphony. The specialist series changes the oscillator, filter and modulation relationships at the centre of the instrument.
The direct voice in two forms.
SUBSTANCE
Mono bass and lead
Driven mixer, pole-mixed transistor ladder, note memory, constant-rate glide and a sixteen-step sequencer.
WORKING CLAP-FORMAT INSTRUMENT
MADRE-8
Polyphonic expansion
Designed to carry the immediate Substance workflow into pads, chords, unison and expressive eight-voice performance.
DESIGN STUDY · ENGINE NOT BUILTDifferent circuits, different interactions.
QUARTET
Oscillator and filter movement
Eight voices built around oscillator interaction, continuous state-variable filtering and repeatable voice character.
WORKING ENGINE + EDITOR
LADDER
Filter and cross-modulation
Designed around a four-pole SSM2040-class filter, a feedback-capable mixer and tightly coupled Poly-Mod routing.
DESIGN STUDY · ENGINE NOT BUILT04 Engineering that serves the instrument
The circuit is the specification.
Measurements matter when they protect a musical relationship: bass body under resonance, pitch across sample rates, voice character on recall and predictable work inside a busy session.
Different filters remain different instruments.
Substance, Quartet and Ladder centre distinct filter structures instead of sharing one generic voice under different panels.
Pitch and articulation survive the sample rate.
Oscillator rates and resistor-capacitor envelope trajectories are checked across six supported sample rates.
Variation stays repeatable.
Pinned voice differences, stable allocation and bounded processing keep character compatible with reliable session recall.
05 The maker
Musicianship and engineering, kept together.
Voltage Synths is built by one person: a musician and software engineer. The musical role, interface, circuit model and measurements are shaped from the same point of view, keeping each instrument focused from the first control to the final render.
06 The first chapter
Explore the first four instruments.
Substance and Quartet have working engines. MADRE-8 and Ladder are design studies. The family is in development and has not been released.