Nightingale vs OpenKJ

Nightingale turns songs from local folders or Plex Media Server, Jellyfin, and Navidrome libraries into karaoke tracks with separated vocals, synchronized lyrics, and real-time pitch scoring. Vocal separation uses the UVR Karaoke model or Demucs. WhisperX transcribes and aligns lyrics word by word, and LRCLIB lyrics are used when available. Japanese, Chinese, Cantonese, and Korean songs can use character-level alignment and romanized readings.

After analysis, users can adjust key and tempo and follow pitch scoring. Lyrics can be provided as timed LRC or Enhanced LRC, pasted as plain text for alignment, or edited. Playback backgrounds include 10 GPU shader options, five Pixabay video styles, and video files. The app supports MP4 and MKV videos and experimental UltraStar song folders. Multiple profiles keep separate score histories; navigation can use a gamepad or touch controls. Native Linux, macOS, and Windows builds use CUDA or Metal acceleration when available, with CPU fallback. A web build can run on a Linux computer on a home network and open in a browser. The app is free and open source under GPL-3.0-or-later, describes itself as having no cloud, and encrypts Navidrome login details on disk.

OpenKJ is open-source karaoke hosting software for karaoke DJs, built and tested for Linux, macOS, and Windows. It integrates with OpenKJ Songbook, which supports web-based song search and submissions. Singers can use Songbook apps for iOS and Android to browse or search a songbook, submit songs with requested key changes, and save favorites. The web submission site can also serve as a venue kiosk, and sign-up requests are sent directly to the host computer. Songbook can optionally display download-vendor catalogs; the project says these are updated daily. OpenKJ SongShop supports purchasing and downloading karaoke files on the fly, with PartyTyme listed as the only available vendor. OpenKJ Tools provides utilities for ReplayGain adjustment, archive handling, zip compatibility, and filename capitalization. Those tools are marked experimental, and the project recommends backing up the library before using them. OpenKJ is free; Songbook starts at $9.99 per month and has a one-month free trial.