- Aug 18, 2017
This is maybe a more general question, but I'm trying to make sense of the various null depth figures.
I've been used to loading files in a DAW, inverting the phase of one of the two and playing them together.
If I do this for a couple of 24bit files I have here, I get a signal at -138dB (the only difference between the two is dither).
But DeltaWave says the null depth is 120dB. And the correlated null depth is 193dB.
What's the explanation for that difference? And I guess correlated null depth measures something else... but what?
Null depth is the average (RMS) of the difference waveform between the two tracks.
Correlated null depth is a measure of how well the two tracks match in time. The larger the value, the smaller the timing errors. It makes sense that there are no timing errors between a dithered and undithered tracks, so the correlated null is very large: the larger it is, the smaller the timing error.