Isolate the bass from any song
Upload a song and StemX splits it into six stems, then opens it with the bass soloed so you hear the line clearly. Mute it instead for a backing track without bass. The first 60 seconds are free with no account.
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What bass players use it for
Learning a bassline
Hear every note without the kick drum and guitars covering it.
Bassless backing tracks
Mute the bass and play your own part over the rest of the band.
Transcribing by MIDI
A full split writes the bassline as MIDI. Bass plays one note at a time in its own range, so it is one of the cleaner parts to transcribe.
Remixes
Lift the original bass to keep it under a new beat, or drop it to write a new one.
How to isolate the bass
- 1
Upload the song
Use an MP3, WAV, FLAC, M4A, OGG, AAC or AIFF file up to 10 minutes long. The preview needs no account.
- 2
Hear the bass on its own
The workspace opens with the bass soloed for the first 60 seconds. Unsolo it and mute it to hear the band without bass.
- 3
Split the full song
Sign in to process the whole track. The bass arrives beside the other stems (vocals, drums, bass, guitar, piano and other) with a MIDI file of the line.
- 4
Check the key and tempo
Every full split shows the key and BPM, so you know what to tune to and where to set your metronome.
How clean is the bass stem?
On the 50 songs of the MUSDB18-HQ test set, the bass stem scored a median SDR of 12.10 dB (95% interval 10.07–13.83 dB). Higher is cleaner; the post linked below explains the method and every figure.
What to expect
Synth bass and 808s come out as bass. A kick drum tuned close to the bass note can leave a little thump in the bass stem.
Very low notes on a small speaker can sound quieter than they are. Check the stem on headphones before you decide something is missing.
MIDI follows the notes, not the technique. Slides, ghost notes and slap are rounded into plain notes, so treat the MIDI as a draft to correct.
Frequently asked questions
How do I isolate the bass from a song?
Upload the song above. StemX splits it into six stems and opens the preview with the bass soloed; sign in to process the whole song.
Can I remove the bass instead?
Yes. Mute the bass stem in the workspace to play along, or download every stem except the bass and mix them in your DAW.
Is it free?
The 60-second preview is free with no account. Full songs use minutes from your plan: the Free plan includes 30 minutes a month.
Which files can I upload?
MP3, WAV, FLAC, M4A, OGG, AAC and AIFF files, up to 10 minutes and 120 MB each.
Does it write the bassline as MIDI?
Yes, on full splits, along with a MIDI file for every other stem. The 60-second preview has no MIDI.
What format is the bass stem?
A 320 kbps MP3 on every plan. Any paid plan or minutes pack adds WAV.