Stem Separation

Nightingale separates lead vocals from instrumentals so you can sing along to the backing track.

Models

UVR Karaoke (Default)

The UVR (Ultimate Vocal Remover) Karaoke model is optimized specifically for karaoke use. It preserves backing vocals in the instrumental track, giving a more natural karaoke experience. Uses ONNX Runtime for inference, with automatic CUDA (NVIDIA) or CoreML (Apple Silicon) acceleration.

Demucs

Demucs by Facebook Research provides an alternative separation model. You can switch between models in the settings.

Video Files

When processing video files (.mp4, .mkv, etc.), Nightingale first extracts the audio track using ffmpeg, then runs stem separation on the extracted audio. During playback, Nightingale uses the source video when available and falls back to a playable converted video when needed.

Guide Vocals

After separation, you can control how much of the lead vocals bleed through the instrumental:

• Toggle: Press G to turn guide vocals on/off
• Volume: Press + / - to adjust the guide vocal level

This is useful for learning new songs or for singers who want a reference pitch.

UltraStar Bundles Skip Stem Separation

UltraStar Deluxe songs that ship with #VOCALS and #INSTRUMENTAL files are used directly during playback — no stem separation is run. If only #AUDIO is provided, Nightingale falls back to running the configured separator on that file. See UltraStar Deluxe for the supported tags.