audio-separation-nodes-comfyui

worklow picture

https://github.com/user-attachments/assets/c5cf20de-a17f-438d-81ac-0c392af669cf

Nodes

Node	Description
Audio Separation	Separate audio into four stems (bass, drums, other, vocals) using Hybrid Demucs.
Audio Combine	Combine two audio tracks by overlaying their waveforms (add, mean, subtract, multiply, divide).
Audio Crop	Crop (trim) audio to a specific start and end time.
Audio Tempo Match	Match the tempo of two audio tracks by time-stretching both to their average BPM.
Audio Speed Shift	Time-stretch or time-compress audio by a given rate.
Audio Get Tempo	Get the tempo (BPM) of audio using onset detection.
Audio Video Combine	Replace the audio of a VIDEO input with a new audio track.

Examples

Separating Voices in a Video

[!NOTE]

In order to load videos into the LoadAudio Node, change this line in your Comfy install to include the video's extension (e.g., .mp4)

workflow.json

https://github.com/user-attachments/assets/c5af418e-7137-4c36-b86e-3352cf558ea8

Replacing BGM with StableAudio-Generated BGM

[!NOTE]

In order to load videos into the LoadAudio Node, change this line in your Comfy install to include the video's extension (e.g., .mp4)

You can use this to replace copyrighted BGM in a video with new BGM. You can set the denoise low, so that the new BGM is still stimilar to the original.

workflow json

https://github.com/user-attachments/assets/a7d5656b-5f8b-439a-936f-6ebb6a0d538a

Remixing Songs with StableAudio

• workflow json
• example output (audio file) with embedded workflow
• example output (audio file) with embedded workflow

Separating Song Vocals

workflow.json

https://github.com/user-attachments/assets/c5cf20de-a17f-438d-81ac-0c392af669cf

Extracting Instrumentals from Songs

• workflow json

 

Stem Mapping

The Audio Separation node uses Hybrid Demucs to split audio into four stems:

Output	Contains
Bass	Bass guitar, sub-bass, low-frequency instruments
Drums	Drums, percussion, hi-hats
Other	Everything else — guitars, keyboards, synths, strings, etc.
Vocals	Singing, speech, vocal harmonies

Looking for a specific instrument like guitar? Guitar is included in the Other stem. To isolate guitar, separate first, then use the Audio Combine node to subtract unwanted elements or further process the "Other" output.

Requirements

librosa>=0.10.2,<1
torchaudio>=2.3.0
numpy
moviep