[robert bristow-johnson] > first, you need to decide of your level is to be measured as peak level or rms > level or mean abs value or whatever.
I'd like to throw in that I've gotten excellent results (for electric guitar) from a design that considers the instantaneous peak level for opening and RMS for closing the gate. (You might even get away without specialised hysteresis logic because the average-over-time property of RMS calculation works towards this effect already.) Another thing that I found very helpful for electric guitars: in the presence of computing equipment, especially the single-coil pickups you find on Stratocasters and similar designs tend to pick up a lot of mains hum. Branching the input signal and notch-filtering out at 50/60 Hz before computing the RMS level allows one to lower the closing threshold further without mains hum keeping the gate open unduly. Cheers, Tim -- dupswapdrop -- the music-dsp mailing list and website: subscription info, FAQ, source code archive, list archive, book reviews, dsp links http://music.columbia.edu/cmc/music-dsp http://music.columbia.edu/mailman/listinfo/music-dsp
