Hmm, any audio processing of this kind needs logarithmic amplifiers to cover the dynamics.

You will not have satisfactory results with just the A/D converter of the PIC.

Have a look at the http://www.picbasic.co.uk/forum/show...?t=2359&page=2 from post 51 and after.

Also PIC are not very fast for the processing you may need.

Ioannis