Stem separation as part of a full music analysis pipeline. Drop a track once, get stems and BPM and key and chords and MIDI in the same pass. Free with daily caps; tool pages stay ad-free.
Splitter.ai gives you stems and stops there. SignalKey gives you the same 4-stem split plus BPM, key, Camelot, chord chart, MIDI export and LUFS check — all in one upload.
No spin — what each tool actually does and where the lines are drawn.
Stem separation as part of a full music analysis pipeline. Drop a track once, get stems and BPM and key and chords and MIDI in the same pass. Free with daily caps; tool pages stay ad-free.
Specialist stem separation service. Fast turnaround on the core 2-stem and 5-stem splits. Free tier with ads, paid plans for higher quality and more stems.
Both have free tiers; SignalKey's is unlimited where Splitter.ai's free tier has track / quality caps.
What each tool does, what it doesn't, and where the gaps are honest.
| Feature | SignalKey | Splitter.ai |
|---|---|---|
| 4-stem split (vocals/drums/bass/music) | ||
| 5-stem split (adds piano / guitar) | ||
| 2-stem split (vocals / instrumental) | ||
| 24-bit WAVSplitter.ai's free tier outputs lower bit depth on some plans. | ||
| No watermark on free tier |
| Feature | SignalKey | Splitter.ai |
|---|---|---|
| BPM detection | ||
| Key + Camelot | ||
| Audio → MIDI | ||
| Chord detection | ||
| LUFS metering |
| Feature | SignalKey | Splitter.ai |
|---|---|---|
| Browser-based | ||
| Batch upload | ||
| API access | ||
| Live mic tools (tuner, metronome) |
Both tools are good. The right answer depends on what you're actually doing.
Not yet. 4-stem (vocals / drums / bass / music) is the standard split. 6-stem isolation is on the roadmap as a Studio feature. If 5+ stems is critical now, Splitter.ai is the better choice.
Methodology: Researched April 2026 against the public Splitter.ai product page. Free tier limits and paid pricing pulled at time of writing. If anything in this comparison reads as inaccurate, please email hello@signalkey.io and we'll update.
Drop a song and see the analysis pass — BPM, key, Camelot, stems, MIDI, LUFS — in one go. Free forever.