Split four-stem audio without watermarks, lift chord progressions, convert melodies to MIDI and check your master against Spotify, Apple Music and YouTube targets — all in one pass.
Producers shouldn't pay $20 a month to figure out what chord that hook is in. SignalKey gives you the same stem split, MIDI extraction and mastering checks the paid services charge for, with full 24-bit WAV downloads, no watermarks, no signups, no monthly bill. Built by a working producer for the bedroom-to-studio path.
Every tool below is free, no signup, no watermark. Click any card to open it.
4-stem split (vocals, drums, bass, music). 24-bit WAV downloads, no watermark, no quality reduction. Use the stems as samples or rebuild a track around the lead.
Polyphonic transcription. Drop a hook or a full mix and get a standard .mid file you can drop into Ableton, Logic, FL or any DAW.
Detects triads, 7ths, sus, add, slash chords. Reports inversions. Useful for re-harmonising someone else's progression in a flip or remix.
Pass / fail readout against Spotify -14, Apple Music -16, YouTube -14, Tidal -14 and SoundCloud -14. True-peak warning at -1 dBTP.
Pull a clean acapella out of any reference for a flip, or strip a hook for an instrumental version.
Match your sample's key to the project key. Camelot code surfaced for harmonic crate-digging across your sample library.
How a working producer uses SignalKey across one production cycle.
You hear a sample candidate on YouTube. Run it through Stem Splitter — clean drums, clean vocal stem, no muddy bleed. Pull the lead into your DAW as your starting hook.
Drop the rough mix into Chord Finder. Save the chord chart. Use Audio → MIDI to grab the bassline, then re-harmonise on top of the imported MIDI.
Bounce a draft. LUFS Meter shows -10 LUFS — too hot for streaming, you'll be turned down. Pull the limiter back, target -14 LUFS, true-peak under -1 dBTP.
Re-run the analyser on the final master. Tempo confirmed, key matches the metadata, LUFS green across all four streaming targets. Ship the upload.
“Pulled a clean a cappella for a flip in 30 seconds. Then re-harmonised the chord chart with Chord Finder. Whole flip went from idea to bounce in an afternoon.”
— Bedroom producer workflowModern productions split very cleanly with minimal bleed. Older or heavily-compressed tracks show some artefacts. We report a per-stem quality score before you download so you know what to expect.
Drop a track and see the full analysis pass — BPM, key, Camelot, stems, MIDI, LUFS — in one go.