I am new to Audacity and have a wav file of a piano performance. I was trying to apply a filter to try to isolate (the most) the left and right hands but did not succeed so far.
You can totally isolate the notes based on pitch (Effect > high pass and effect >low pass with the sharp split at middle C 256), but you can’t isolate the harmonics and overtones. And all the overtones overlap.
This is an analysis of one single piano note, G, way down on the keyboard left.
You can’t even find middle C in that mess, 256Hz. or the orchestra A 440Hz.
Get the performer to play on two electronic pianos one above the other and record them as separate WAV files, or combine them into a stereo show with one piano on the left, one on the right. I have two keyboards, one an “ironing board” type and one a floor model, so I could do this pretty easily.