[chuck-users] powtodb and rmstodb in Chuck

[jakob kaiser]

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
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