FM Synthesizer — Python GUI, Faust DSP, Wwise Plugin

A cross-technology FM synthesizer project featuring:

• A standalone Python application with a modern Tkinter GUI
• A Faust DSP source with generated C++ for real-time audio
• A Wwise Source plugin integration

Runs on Windows and supports real-time synthesis, presets, musical scales, and keyboard play.

• License: MIT
• Author: Li Szaj

Features

• FM synthesis with carrier + modulator
• Polyphony up to 3 voices
• ADSR envelopes per voice
• Hard Sync with ratio presets
• AM modulation across components
• Stereo processing with width control
• Preset save/load/delete
• Musical scales and keys
• CPU usage monitor
• Two-tab GUI: “Play” and “Design” with accordion sections

Repository Structure

• faustFM/fm_synth_standalone.py — Python GUI app
• faustFM/fm_source.dsp — Faust DSP source
• faustFM/build/FaustDSP.cpp — Generated C++ DSP
• build/FaustFM/ — Wwise plugin sources and solutions
• faustFM/run_fm_synth.bat — Windows launcher (optional)
• faustFM/presets/ — User presets directory

Quick Start (Python GUI)

Requirements: Python 3.11+, pip, Windows

1. Clone the repository

git clone https://github.com/Atomcio/Faust_vst_builder.git
cd Faust_vst_builder

2. Create and activate a virtual environment

python -m venv .venv
.\.venv\Scripts\activate

3. Install dependencies

pip install pygame numpy psutil
# Optional performance
pip install numba

4. Run the synthesizer

cd faustFM
python fm_synth_standalone.py

Or double-click run_fm_synth.bat on Windows.

GUI Overview

The GUI is split into two tabs for clarity:

• Play

  • Trigger button for quick note tests
  • Master Volume
  • FM Amount
  • Mix Level
  • Hard Sync (enable + ratio)
  • “Open Presets...” for quick access

• Design (accordion sections)

  • Oscillators: ranges, frequency, amplitude, wave shape for Osc1/Osc2
  • ADSR Envelopes: attack/decay/sustain/release per voice
  • Scale: musical key, scale type, octave, buffer size, CPU monitor
  • Presets: save, load, delete, list

Keyboard Controls

• Tabs: Ctrl+1 switches to Play, Ctrl+2 to Design
• Piano mapping (QWERTY, depends on octave): typical chromatic mapping from Q

Audio Engine (Python)

• Real-time block generation via pygame.mixer thread
• FM deviation computed per sample based on modulator and FM index
• Envelope shaping via ADSR per voice
• Stereo output with width control
• Master gain in dB converted to linear

DSP (Faust)

• faustFM/fm_source.dsp defines carrier/modulator, FM index, AM envelopes, stereo processing
• Generated C++ in faustFM/build/FaustDSP.cpp with optimized sine table

Wwise Plugin (Windows, Visual Studio)

Directory: build/FaustFM

• Solutions:
  • FaustFM_Windows_vc170_static.sln
  • FaustFM_Windows_vc170_shared.sln
• Config: FaustFMConfig.h with CompanyID and PluginID
• Build in Visual Studio 2022 (v17) and install into Wwise

Presets

• Saved under faustFM/presets/ in JSON format
• Save current, load selected, delete, refresh list

Configuration

• Sample rate: 44100
• Buffer size: adjustable in the Scale section
• Defaults: fm_amount=8.0, mix_level=0.8, ADSR: A=0.0 D=0.2 S=0.7 R=0.3, Hard Sync on

Troubleshooting

• No audio: ensure pygame mixer initializes; try larger buffer size
• High CPU: reduce polyphony, increase buffer size; Numba optional
• Osc2 locked: intentional when Hard Sync is enabled

Contributing

• Fork, create a feature branch, keep changes focused, open a PR

License

MIT — see LICENSE.

Acknowledgements

• Pygame community
• Faust and stdfaust.lib
• Audiokinetic Wwise SDK