Sometimes I can get decent results with Izotope Music Rebalance, but when I need to remove only guitars and there's a keyboard at same time it gets impossible for me.
What would be the best options ? any technique, plugin, etc?

 

if the guitars are panned you could try something like zplane peel... but I have seen some ai websites that isolate things as well... albeit better than peel in some instances.

 

Taking iZotope RX as a reference...
HitNMix seems to be the best "offline" track isolation program
But a couple of those online AI sites are still better

 

SpectraLayers Steinberg

 

you guys are amazing. Thank you very much !

 

Hi o/, founda online "KI" service. give it a try
https://vocalremover.org/

Greetings and Peace

 

Spleeter or something like lalal.ai might work okay, but dont expect wonders.

It depends a lot how the track was mixed. For example if the vocal is in mono or stereo in the track if other elements peak into the vocal frequency - prime example is an acid sound, which has a big frequency range.

In the end we are talking about overlapping frequency ranges, when you put two or more audio signals together (summing!). I wonder when AI via machine learning are able to replicate the overlapping part of the frequency ranges?

Studio acapella, versus "AI" extracted acapella - using to find out how to replicate the missing pieces. If this is figured out, we will have stunning HQ stems of music tracks.

 

If there is high pitch artefacts, you could try to use zynaptiq unchirp to remove those

 

Izotope music rebalance works fine, the problem is removing only keyboards or guitars. It removes both at same time, cant choose what you want to remove between them.