On 28 Dec 2001, Andrew (Andy) W. Schmeder wrote:
If the sample values going into [dac~] are outside of [-1, 1] then you are clipping the signal... (that's the soundcard clipping not the amp) solution; place before the dac~, [/~ n] for n = the number of signals you've added together.
andy
Just curious about this - I've seen several times lately on various lists, the recommendation to divide by the number of voices, but I've always thought that if the signals aren't correlated, then scaling by the inverse of the RMS sum of the signal amplitudes is what would result in the same overall output level as just one signal by itself.
At least this would have to be mathematically true for white noise, would it not?
Consider for example, mixing a full orchestra - would you really wnat divide by the number of instruments in the orchestra? Would you then be able to hear a solo?
My guess is that there is a tradeoff between keeping the final RMS output the same as that of an individual signal (1/RMS-sum) vs an absolute guarantee that there is zero chance of clipping (1/sum-of-peak-amplitudes).
I'd love to be enlightened about this.
Larry