Simpler demudder

 

Published for paid users of x-minus.pro (when you pick Roformer model for instrumentals, buttons with methods appear; it is only applied for instrumentals, not vocals)

 

In his own words:

“

1. Separate the song into vocals and music

2. Invert the phase of the vocal and mix it with the music

3. Now separate this mix

4. Mix the vocals with the input song

 

It actually works more complicated than that. I added a high pass filter since the demudder is not needed at low frequencies.”

Probably something from the 100-250 Hz range.

Actually, Aufr33 used following ffmpeg command:

“ -filter_complex "[0:a]highpass=f=900[hp1];[0:a][hp1]amerge,pan=stereo|c0=c0-c2|c1=c1-c3[lp];[1:a]highpass=f=900[hp2];[lp][hp2]amix=inputs=2:duration=longest:normalize=0[out]"”

 

Rephrased by becruily

 

“use Roformer on a song

phase invert the vocal file and combine it with the instrumental

separate again using the same model

combine the original song and vocals (no inversion or anything) and you will get demudded inst

 

this is for instrumental, if you want demudded vocals just switch the two words (acapella and instrumental)”

 

Video how to apply demudder method

 

Notes

 

- For HQ 4 and at least denoise model enabled, the method seems to produce more vocal residues, so it might be feasible more for Roformers (it’s used optionally for Kim Mel-Roformer on x-minus).

 

- "xminus demudder is more pleasing to the ears" - isling

 

- Some people might still prefer max_mag ensemble on x-minus or mel-roformer + bs-roformer ensemble in UVR

 

Phase fixer on x-minus for unwa inst v1 model copies phase from Kim Mel-Roformer model.