Instruo Tona
Analogue VCO with West Coast wavefolder built in
12 HP Eurorack module
The Instruo tòna is an all-analogue voltage controlled oscillator that generates four classic waveforms (square, sawtooth, triangle, sine) plus a fifth output driven by a built-in analogue wavefolder derived from classic West Coast timbre circuits. It combines East Coast oscillator fundamentals with West Coast harmonic complexity, offering linear FM, hard sync, and voltage-controlled wavefolding for rich, evolving timbres.
Features
- All analogue signal path
- Four classic waveform outputs: square, sawtooth/ramp, triangle, sine
- Fifth wavefold output driven by built-in analogue wavefolder
- Wavefolder derived from classic West Coast timbre circuits
- 1V/Oct pitch tracking input
- Linear FM input with attenuator
- Hard oscillator synchronisation via Sync Input
- Voltage-controlled wavefolding with CV input and attenuator
- Wavefold fader for manual fold amount control
- Sync voltage threshold: 2.5V
- Reverse polarity protection on power connector
- Bipolar control voltage inputs for 1V/Oct and Linear FM
Controls & Jacks (14)
- Coarse— Controls the fundamental frequency of the oscillator, changing the pitch of all waveforms. Turning clockwise increases frequency.
- Fine— Fine control of the oscillator's fundamental frequency relative to the Coarse knob setting. Turning clockwise increases frequency.
- Sine Output— Sine waveform output.
- Wavefold CV Attenuator— Determines the depth of applied frequency modulation. Turning clockwise increases the depth of frequency modulation.
- Linear FM Input— Bipolar control voltage input for the frequency parameter of the oscillator. Audio rate signals will add non-harmonic sidebands to the origi
- Linear FM Attenuator— Controls the depth of control voltage modulation applied to the wavefold parameter.
- Square Output— Square waveform output.
- Triangle Output— Triangle waveform output.
- Sawtooth/Ramp Output— Sawtooth/Ramp waveform output.
- Wavefold Output— Folded waveform output. Waveform determined by the Wavefold parameter.
- Wavefold CV Input— Bipolar control voltage input for the Wavefold parameter. Control voltage is summed with the fader position.
- Wavefold— Controls the amount of wavefolding applied to the waveform at the Wavefold Output. Fully left resembles a sine waveform; fully right produce
- 1V/Oct Input— Bipolar control voltage input calibrated to 1 volt per Octave. Traditionally used for frequency control (musical pitch) sent from a sequence
- Sync Input— Hard synchronisation input. On a rising edge signal the oscillator's cycle will reset. Hard edged signals such as Sawtooth/Ramp and Square w
How-To Guides
- Classic East Coast Synth Voice
- Linear FM Synthesis Voice
- Audio Rate Wavefolder Self-Patch
- Slow LFO Wavefold Sweep
- Hard Sync Timbral Sweep
- Envelope-Controlled FM Depth
- West Coast Synthesis Voice
- Detuned Dual Oscillator Unison
- Percussive Hard Sync Sweep
Explore the interactive Tona panel on BleepDex — tap any control to learn what it does.