BytePlus Voice and Background Audio Separation vs Demixr

BytePlus Voice and Background Audio Separation is an API service that processes audio or video files into vocal and background tracks. Drama and Narrate scenes can further separate vocals, music and sound effects. BytePlus lists video editing, vocal enhancement, video translation and voice cloning, and ASR optimization as use cases. Requests create asynchronous separation tasks, checked through polling or event notifications. Inputs must be publicly accessible HTTP or HTTPS URLs, with MP4, FLV, TS, AVI, MOV, WMV, MKV, MP3, M4A and WAV supported. Outputs can be AAC, MP3, WAV, M4A or FLAC, with AAC as the default; result URLs remain valid for 24 hours. The listed plan costs $0.01 as a one-time purchase, billed per minute of input source duration. Storage and VOD CDN distribution may add fees. The service is available through API, Linux, macOS and web, with Console, CLI and OpenAPI deployment methods.

Demixr is a web service for processing audio, with tools for separating vocals and instruments, removing reverb, marking speech, and analyzing BPM and key. Its Pro 1.5 vocal separation has Voice mode for complex mixes, live recordings, or speech over music, and Music mode for songs and covers or separating vocals from accompaniment. A separate stem tool uses Demucs to split music into vocals, drums, bass, and other parts. For dereverb, Demixr recommends isolating vocals first; applying the effect to a mixed track can cause artifacts or distortion. VAD provides editable speech-segment markers and batch export, though detection may be inaccurate with quiet vocals or noisy recordings. BPM analysis includes tempo, key, and Camelot values, with optional tap-to-sync. The free plan costs nothing and includes 10 minutes of audio monthly, a 10 MB upload limit, two VAD uses, queued processing, and no WAV downloads. Paid one-time plans start at $4/mo, without automatic renewal. Uploads and outputs are deleted within 24 hours by default.