SInES Tools: Pulse-Forming Synthesizer (Pulse-forming Synthesis, as it was used in the Variophon/Martinetta wind synthesizer)
(according to Fransson 1966/67, Fricke 1975, Voigt 1975, Auhagen 1987, Blens 1993, and Oehler 2008)
1. Choose a preset or starting waveform: Select an instrument preset from the dropdown menu, click a quick-setup model (Bassoon, Oboe, or Trumpet), or choose a basic waveform (rectangle, half-sine, triangle, cosine) in the Pulse Form module.
2. Fine-tune pulse shape and timing: Adjust the Pulse Width (t) to control the formant frequencies, tweak Pulse Form Transition (morph) to blend between sharper and softer waveforms, and set the symmetry with Upward Slope if using triangle/cosine pulses.
3. Shape the timbre with filters: Engage the High-Pass or Low-Pass filters in the Radiation (Filter) module and adjust cutoff frequencies and slopes (dB/octave) to simulate acoustic instrument radiation.
4. Add modulation (optional): Activate the Modulation (LFO) section and select a target (such as PWM, AM, FM, or pitch vibrato) while adjusting rate and depth for expressive sound changes.
5. Play notes and inspect visualizations: Trigger notes using the on-screen keyboard, your PC keys (A–K), or a connected MIDI controller. You can toggle Velocity Sensitivity to control loudness and waveform morphing dynamically by clicking vertically along the keys, and monitor the real-time changes in the oscillogram and spectrum displays
Time Domain (Oscillogram) 3 Perioden
Frequency Domain (Spectrum)

Pulse Form (in fff)

RectangleHalf Sine

Time Parameters

Automatically calculates pulse width, register, dynamics, and filter according to Oehler (2008).
When the pitch changes on the keyboard, the period length changes automatically. The pulse width remains constant, which keeps the formants fixed.

Radiation (Filter)

Modulation (LFO)

(acc. to Oehler & Reuter 2007)

Global & Display

Keyboard Controls PC keyboard: A W S E D F T G Y H U J K
(always plays the first visible octave)
C3-C5
Velocity Sensitivity
Examples from the literature
Pulse-forming Synthesizer © 2026 by Christoph Reuter and SInES (last modified: 11.10.2026) is released under MIT License
How to cite: Reuter, C. (2026). SInES Tools: Pulse-forming Synthesizer. Web Application https://sinestools.univie.ac.at/pulseformer.htm