# Bass Line Extractor AI Pull the bass line out of any full mix as isolated audio, a MIDI transcription, or both — powered by local neural stem separation. > Canonical page: https://elysiatools.com/en/tools/bass-line-extractor-ai - **Category:** Media - **Keywords:** bass line extractor, bass separation, isolate bass, bass stem, bass to midi, demucs, basic pitch, bass transcription, learn bass line, bass cover ## Overview Two neural stages run locally in Node. First, HT-Demucs FT (ONNX, the same four-stem model behind our stem separator) separates the upload into drums / bass / other / vocals and keeps only the bass stem. Second, on request, Spotify Basic Pitch (TensorFlow.js) transcribes that stem into MIDI notes — the separated bass is near-monophonic, which is exactly the input Basic Pitch is strongest on. A 30 Hz high-pass can trim the DC-ish rumble separation sometimes leaves. Output modes: isolated bass audio (WAV/FLAC/MP3), a .mid file (Electric Bass program, wall-clock timing at 120 BPM header), or a ZIP with both plus an analysis.json (RMS, low-band share, note count, pitch range). This is an AI draft, not ground truth: expect some bleed from kick drums, missed ghost notes, and octave jumps on very low or distorted bass. Mono-ish mixes and loud, clean bass lines fare best. Up to 3 minutes per job. ## Inputs - **Music track (full mix)** (file) - **Extract** (select) - **Bass audio format** (select) - **Sub-bass cleanup (30 Hz high-pass)** (checkbox) - **MIDI sensitivity** (select) ## When to use - You want an isolated bass audio track (WAV, FLAC, or MP3) from a full mix to practice, mix, or create a backing track. - You need a MIDI transcription of a bassline to import into your DAW or notation software for learning and re-synthesis. - You want a complete extraction archive containing clean bass audio, a .mid sequence, and a JSON analysis report. ## How it works - HT-Demucs FT processes the uploaded audio file to separate drums, bass, vocals, and other instruments, isolating the bass track. - An optional 30 Hz high-pass filter cleans sub-bass DC rumble and low-end artifacts left behind by source separation. - Spotify Basic Pitch analyzes the isolated near-monophonic bassline and converts pitch and timing into a standard MIDI file. - The tool packages your chosen outputs—isolated audio file, .mid file, or a ZIP with both plus an analysis.json—for instant download. ## Use cases - Bassists transcribing complex basslines by generating isolated practice audio alongside editable MIDI notation. - Music producers extracting isolated bass stems to replace synth bass presets or re-amp bass tracks in a remix. - Arrangers studying harmonic progressions and root note motion directly from full song recordings. ## Frequently asked questions ### What audio formats and length limits are supported? You can upload standard audio files up to 100 MB and up to 3 minutes in length. ### How does the sub-bass cleanup filter help? The 30 Hz high-pass filter removes non-musical sub-bass rumble and DC offset introduced during stem separation. ### What is the difference between the MIDI sensitivity options? Gentle detects fewer notes to reduce false triggers, eager captures subtle articulations and extra notes, and standard balances note accuracy. ### Why does the MIDI file have a 120 BPM header? The MIDI uses wall-clock timing under a default 120 BPM header to maintain exact real-time playback alignment. ### What information is included in analysis.json? The ZIP package includes an analysis.json reporting audio RMS levels, low-band energy share, total transcribed note count, and detected pitch range. ## Related tools - [Noise Profile Extractor](https://elysiatools.com/en/tools/audio-noise-profile-extractor): Capture a noise fingerprint from a selected region of your audio - floor level, third-octave spectrum, hum harmonics, classification - then reuse it to denoise this file or any other file. - [Subtitle Translation Sheet (CSV Excel)](https://elysiatools.com/en/tools/subtitle-translation-sheet): Round-trip subtitles through the spreadsheets translation teams actually use: export SRT/VTT cues to a CSV or Excel table (index, start, end, source, target, notes) and re-import the filled sheet as translated SRT — timings locked, in-cell line breaks preserved, and semicolon CSV with UTF-8 BOM for European Excel. - [Audio Metadata Remover](https://elysiatools.com/en/tools/audio-metadata-remover): Strip technical metadata from an audio file for privacy before sharing - [Album Art Extractor](https://elysiatools.com/en/tools/audio-album-art-extractor): Extract the album art from an audio file - [Audio Ambience Loop Generator](https://elysiatools.com/en/tools/audio-ambience-loop-generator): Extract the background ambience/room tone from a fragment and generate a seamless loop of any target length. - [Extract Center Channel](https://elysiatools.com/en/tools/audio-center-channel-extract): Extract the center channel from a surround audio file or video audio track - [Extract Left Channel](https://elysiatools.com/en/tools/audio-left-channel-extract): Extract only the left channel to a mono file - [Audio Melody Contour Extractor](https://elysiatools.com/en/tools/audio-melody-contour-extractor): Extract a dominant melody path from audio and export MIDI, note events, a pitch contour, SVG, and JSON in one ZIP. ## Samples - [Copyright-Free FLAC Audio Samples](https://elysiatools.com/en/samples/flac-samples): Lossless FLAC audio samples for testing and development, mirrored from MP3 set with nature sounds and meditation music - [Copyright-Free MP3 Audio Samples](https://elysiatools.com/en/samples/mp3-samples): Collection of royalty-free audio samples for testing and development purposes including nature sounds, meditation music, and ambient audio - [Copyright-Free WAV Audio Samples](https://elysiatools.com/en/samples/wav-samples): Uncompressed PCM WAV audio samples for testing and development, mirrored from MP3 set with nature sounds and meditation music - [Copyright-Free Raw PCM Audio Samples](https://elysiatools.com/en/samples/pcm-samples): Raw PCM s16le audio samples featuring nature ambience and relaxing music for waveform, playback, and conversion workflows