Using microphone arrays to eliminate background music

The best way to put an image…

My account was likely censored/restricted, so even inline images didn’t show. Discuss at Why am I not allowed to post images?

Audacity does not include such an effect, but it does provide a programming language to enable users to create custom effects. The programming language is called “Nyquist”. More information here in the manual: > Nyquist - Audacity Manual

Thanks Steve. I don’t know this language. I fear that I am too busy to learn it. I hereby offer \$10-\$50 for someone to write it on the condition that audacity+Nyquist has multi-core/threading. I can supply some sample audio (L(t) + R(t)) data to work with as well.

Suggested algorithm: let a=c=10, b=0.5, tauS=0, minimize S^2 or |S(tauN)| just as a function of tauN. (This assume the noise is at least 5% as loud as the signal. If cpu time is an issue listening to the files and making human guesses is more important.) Since there’s a denominator there needs to be a softening constant that is a function of the precision absolute value added to prevent errors. Then keep tauN fixed and minimize S^2(tauS). Then re-minimize S^2(tauN, tauS) … until there is convergence to a microsecond (1e-6 seconds or .03 mm.) in both variables. Next minimize S^2(b), then get convergence of S^2(tauS,tauN,b). Now do min(S^2(a)) and then min(S^2(tauS,tauN,b,a)). Lastly, do min(S^2(b)) and then min(S^2(tauS,tauN,b,a,b)). The output is N(t-tauN) and S(t-tauS) in a new stereo track.