Hi, I'd like to know how decibel is defined in the standard functions of chuck, namely powtodb and rmstodb. After what I've read so far decibel is defined as: 20*log(soundToMeasure/referenceValue) Is that the formula used for these functions? And if yes, what is the reference Value here? Also, did I get the relation between the float values used for the samples of audio signals in chuck and dB right if I would measure dBs like this: - suppose I want to get the maximum dB of an audiosignal. Would it be sufficient to look for the greatest float value in the signal, and then apply powtodb(maximumValue) to it? - suppose I want to get the average dB of an audiosignal. Would I have to take all values of the signal, calculate the root mean square after the formula used in statistics and then apply rmstodb? But then I still don't understand why I need another function for this one. So, what is the difference between rmstodb and powtodb. Have a nice day Jakob _________________________________________________________________ Express yourself instantly with MSN Messenger! Download today it's FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/