AI-powered sample pack factory

Turn any song into an MPC-ready sample pack with one click.
50 artist presets · 7 chop modes · 128 pads · zero configuration.

Quick Start · How It Works · Features · Roadmap

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Quick Start

git clone https://github.com/dnakul2000/crates.git
cd Crates
./launch.sh

That's it. The launcher creates the virtual environment and installs everything on first run. Subsequent launches skip straight to the app.

Requirements: Python 3.10+ and an internet connection for first-time AI model downloads.

How It Works

Crates is a four-stage pipeline — each stage is its own tab in the app:

flowchart LR
    A["<b>Download</b><br><i>Spotify URL<br>→ YouTube → audio</i>"]
    B["<b>Separate</b><br><i>Demucs AI<br>→ 4 stems</i>"]
    C["<b>Generate</b><br><i>Artist presets<br>→ 128 chops</i>"]
    D["<b>Play</b><br><i>4×4 pad grid<br>→ MIDI / keys</i>"]

    A --> B --> C --> D

    style A fill:#2d2d2d,stroke:#C97F3A,color:#e8e0d6
    style B fill:#2d2d2d,stroke:#C97F3A,color:#e8e0d6
    style C fill:#2d2d2d,stroke:#C97F3A,color:#e8e0d6
    style D fill:#2d2d2d,stroke:#C97F3A,color:#e8e0d6

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Features

Artist Presets

50 presets modeled after real producers and their chopping philosophies — not genre tags, but production approaches:

Category	Producers
Soul Flippers	Kanye, Just Blaze, RZA, Hi-Tek, 9th Wonder
Crate Diggers	Madlib, DJ Premier, Pete Rock, J Dilla, Alchemist
Boom Bap Architects	DJ Muggs, Large Professor, Havoc, Buckwild, Diamond D
Beat Scientists	Flying Lotus, Knxwledge, Kaytranada, Monte Booker
...and 30 more

Each preset defines its own chop modes, effect chains, pad mapping strategy, and sample selection criteria.

Chop Modes

Mode	Description
onset	Musical event boundaries detected by spectral flux
beat_grid	Quantized slices locked to BPM
phrase	Longer musical phrases based on structural analysis
transient	Attack-point detection for percussive material
granular	Micro-slices for texture and resynthesis
syllable	Vocal-aware segmentation
random	Controlled chaos with configurable density

Audio Engine

• Quality gate — auto-rejects stem bleed, silence, clipping, and spectral artifacts
• Smart selection — diversity-aware algorithm picks the most interesting 128 samples, not just the loudest
• Group-aware normalization — preserves dynamics between related samples (LUFS or peak, per-group)
• Authentic effects — Voss-McCartney vinyl crackle, tape wobble, granular resynthesis with per-grain pitch spread, perceptual intensity curves

Output

• 24-bit WAV files with A01_kick_drums.wav naming convention
• MIDI file (.mid) with velocity-mapped pad triggers
• MPC program (.xpm) for direct import into MPC Software/hardware
• BPM and key tagging in the pack manifest
• Drag-and-drop from pads directly into your DAW

Hardware

• Auto-detects Akai MPC Mini MK3 and other class-compliant MIDI controllers
• 16 pads × 8 banks = 128 pad slots
• Keyboard fallback for controller-free use

Installation

One-line launch (recommended)

./launch.sh

Manual setup

python3 -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
python main.py

Standalone macOS app

./build.sh
# → dist/Crates.app (drag to /Applications)

The built app is fully self-contained. Runtime data lives in ~/Documents/Crates/.

Tech Stack

Component	Technology
GUI	PyQt6
Stem separation	Demucs (via audio-separator)
Audio analysis	librosa, scipy
Effects	Pedalboard (Spotify)
ML/classification	scikit-learn, PyTorch
MIDI	mido, python-rtmidi
Audio I/O	soundfile, sounddevice
Download	yt-dlp
Validation	Pydantic

Roadmap

• Universal MIDI controller support — any class-compliant controller, auto-detect, configurable mapping
• Local file import — skip the download step, drag in your own audio
• DAW export formats — Ableton Live Sets (.als), Logic Pro, FL Studio (.flp)
• AU/VST plugin — use Crates inside your DAW
• Ableton Link — tempo-sync with other apps and devices
• Batch CLI mode — process multiple songs headless

License

This project is licensed under CC BY-NC 4.0 — free to use, share, and modify for non-commercial purposes. See LICENSE for details.

Disclaimer

Crates is provided for personal and educational use. Users are responsible for ensuring they have the rights to any audio they process. This tool does not host, distribute, or provide access to copyrighted content.