MashupMaker

MashupMaker is a browser‑based tool that lets you place the vocal track from one song onto the instrumental parts of another. After you upload two audio files, the service separates each into four stems, keeps the chosen vocal, and aligns it with the backing track's tempo and key before offering a preview and MP3 download.

The workflow is split into three stages. First, both uploads are processed by a stem‑separation model that extracts vocals, drums, bass and “other” elements. You indicate which song supplies the vocal; the other song provides the drums, bass and other parts, so two lead vocals never overlap. Next, the system checks the pair for compatibility: a tempo difference greater than 12 % or a key difference beyond five semitones causes the pair to be rejected before any charge is applied. If the key reading is uncertain, the mix is still produced with a note suggesting a one‑semitone adjustment. Finally, the vocal is time‑stretched and pitch‑shifted to match the backing track, the drum tracks set the start point, and you can fine‑tune levels (‑24 dB to +12 dB per part), mute stems, drag the vocal start, or shift pitch by a semitone. The completed mashup can be played back in full, vocals only, or backing only, and then downloaded as a 192 kbps MP3.

MashupMaker is aimed at users who want a quick way to create a vocal‑over‑beat mashup without using a full digital audio workstation. New accounts receive one free mashup with songs up to 60 seconds each; subscribers can work with files up to 6 minutes and 20 MB. The tool supports MP3, WAV, M4A, OGG and WebM formats, keeps uploads private for 24 hours, and does not require any credits for re‑exports. Because the service runs entirely in the browser, you do not need to install software, and all processing happens client‑side after the initial stem separation.

Key features

• Automatic four‑stem separation for each uploaded track
• Tempo matching for gaps up to 12 % and key shifting up to five semitones
• Level control per stem from –24 dB to +12 dB, with mute and drag‑to‑align options
• Preview of full mix, vocals only, or backing only before download
• Export as a 192 kbps MP3, with unlimited free re‑exports
• Private storage that deletes files after 24 hours