Tunerize

    

Re-render any audio as chiptune — or through any SoundFont you choose. Drop in an MP3 or WAV, pick Chiptune Mode (built-in retro synths, zero setup) or any .sf2 (piano, brass, SC-55, anything), and get back a WAV in that style.

Tunerize does the full pipeline locally: audio → MIDI (via Spotify Basic Pitch) → cleaned MIDI → render. Two render paths:

• Chiptune engine (built-in) — three chip models: NES APU-style (2 pulse + triangle + noise), Game Boy DMG (2 pulse + 4-bit wave + noise), and SNES SPC700-style (8 voices with multi-harmonic waveforms, Gaussian warmth filter, and echo). No SoundFont needed.
• SoundFont engine (FluidSynth) — anything .sf2 you can find.

One window, one button, no cloud.

Features

• Built-in chiptune engines — NES-style (2 pulse + triangle + noise) and Game Boy DMG-style (2 pulse + custom wave + noise) synths ship in the app. Zero install, instant retro.
• Online SoundFont browser — search and install SF2s from public libraries (musical-artifacts.com, GitHub topic:soundfont, and Reddit r/soundfonts leads) without leaving the app. License + author shown for every result.
• Bring-your-own SoundFonts — Drop .sf2 / .sf3 into soundfonts/; Tunerize scans, validates, lists them, and keeps your recent picks at the top.
• Preset-aware SoundFont workflow — Tunerize reads bank/program names from .sf2 / .sf3 files, lets you choose a preset, and can render a short preview before conversion.
• Drag-and-drop input — Drop supported audio files directly on the window, or use the file picker.
• One-click conversion — Open audio, pick mode, hit Convert. WAV out.
• Stem separation (optional) — Pre-split mixed tracks with Demucs for cleaner transcription on full songs.
• MIDI export — Keep the intermediate .mid for use elsewhere.
• MIDI cleanup — Quantize, remove tiny artifacts, normalize velocity, transpose. All defaults sane; tweak in Advanced.
• Chiptune voice mixer — Pick the chip engine, then adjust, mute, or solo the built-in pulse, triangle/wave, and noise voices before rendering.
• Force-preset mode — For non-GM SoundFonts, force every note through one preset.
• Background worker — UI never freezes during long conversions.
• Dark by default — Catppuccin Mocha theme.

Install (from source)

Prerequisites

• Python 3.11 or 3.12 (3.13 may work but is not yet validated against basic-pitch ONNX)
• FluidSynth — only required for SoundFont mode; Chiptune Mode works without it.
  • Windows: winget install FluidSynth.FluidSynth or download from fluidsynth.org and put fluidsynth.exe on PATH
  • macOS: brew install fluid-synth
  • Linux: sudo apt install fluidsynth (or distro equivalent)
• FFmpeg (MP3 decoding) — bundled via imageio-ffmpeg; no separate install needed

Setup

git clone https://github.com/SysAdminDoc/Tunerize.git
cd Tunerize
python -m venv .venv
.venv\Scripts\activate          # Windows
# source .venv/bin/activate     # macOS/Linux
pip install -r requirements.txt
python -m app.main

Get some SoundFonts

Three options:

1. Use the built-in browser (easiest) — Open Tunerize, switch to SoundFont mode, click Browse Online…. Searches musical-artifacts.com, GitHub topic:soundfont, and Reddit r/soundfonts leads. Direct .sf2 / .sf3 / archive links download in one click; GitHub repositories are saved as ZIP bundles; Reddit discussion-only results open in your browser for review.
2. Drop your own into soundfonts/ (.sf2 / .sf3). Restart or hit ↻ to re-scan.
3. Recommended grabs:
   • FluidR3 GM (MIT, the FluidSynth default, ~140MB) — search the browser for "FluidR3"
   • GeneralUser GS (CC BY-SA, full GM bank, ~30MB) — search "GeneralUser"
   • 8-bit / NES — search "NES" or "chiptune"
   • SC-55 / SC-88 — Roland synth recreations

Usage

1. Open Audio — pick or drop an MP3, WAV, FLAC, OGG, M4A, AIFF, or AIF.
2. Choose render mode:
   • Chiptune Mode — uses the built-in NES-style synth. No SoundFont required.
   • SoundFont Mode — pick a .sf2 from the dropdown, click Add… to import one from disk, or click Browse Online… to grab one from a public library. Recently installed or used SoundFonts appear first.
3. (Optional) In Advanced, choose a SoundFont preset and click Preview to audition a five-second phrase. Enable Force all notes to selected preset for non-GM banks.
4. (Optional) Toggle Stem separation if your input is a mixed song.
5. (Optional) Open Advanced for transpose, quantize grid, chip engine, chiptune voice mix, force-preset mode, output folder.
6. Convert. Watch the progress bar and log panel.
7. Output lands at <input_dir>/<song>__chiptune.wav (or __<soundfont>.wav), plus .mid if you opted in.

Limitations

• Basic Pitch is best on monophonic / lightly polyphonic audio. Single instruments, melodies, vocals: great. Full mixed songs: messy without stem separation.
• Stem separation adds 1–3 minutes per song (Demucs is heavy). It's opt-in for that reason.
• Chiptune Mode is 4-voice polyphonic (NES-style). Dense polyphonic input gets thinned via voice-stealing. That's the retro authenticity, not a bug.
• General MIDI assumption (SoundFont mode): Tunerize starts from the selected SoundFont preset. For GM-compatible SoundFonts this is usually bank 0, preset 0: "Acoustic Grand Piano." Use Force all notes to selected preset for non-GM banks.
• No realtime monitoring yet — preset preview and conversion are rendered offline to WAV.

Roadmap

See ROADMAP.md. Highlights:

• v0.2 (this release): Online SoundFont browser
• v0.3: Bundled FluidSynth, Windows binary, FluidR3 onboarding, SNES / Genesis chiptune engines
• v0.4: Polyphone integration (bundled SF2 editor — GPL, ships in installer)
• v0.5: Built-in SF2 creator (sample → SF2, native, no external tool)
• v0.6: MP3/OGG/FLAC export, batch mode, genre presets, CLI mode

Development

pip install -r requirements-dev.txt
pytest                       # run tests
python -m app.main           # run the app
ruff check .                 # lint

Build a Windows binary (after PyInstaller is installed):

python build/build_windows.py

License

MIT. Built on:

• Spotify Basic Pitch — Apache 2.0
• FluidSynth / pyfluidsynth — LGPL 2.1 / Public Domain bindings
• PySide6 — LGPL 3.0
• Demucs — MIT
• pretty_midi, mido, librosa, soundfile