Some sort of sloping? about cqt-analyzer HOT 2 OPEN

Looking at it with spaced sine waves, everything looks appropriately constant. The low frequencies do take much longer to appear and be stable/constant in the analyzer though. I wonder if it has something to do with the time resolution at the lower frequencies.

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Hello and thanks for the input!

The slope with white noise you are observing, to my knowledge, is a property of the Constant Q Transform (CQT).
Looking at the CQT as a collection of logarithmic spaced band-passes, the bandwidth of the these filters increases with frequency. Hence, with rising frequency, they integrate over a bigger absolute frequency range, creating the observed slope.
With sine tones, it behaves differently, because these only contain one distinct frequency and don't sum with increasing bandwidth.

The FFT has a constant bandwidth across all frequency bins and therefore doesn't show the slope.

Future versions of the plugin could contain a parameter to actually apply a slope and observe equal power for white noise, but then its a trade-off observing single sine tones with equal magnitude independent of frequency. Maybe there is a clever way to handle this, but I have to think about it.

As you already guessed, the time resolution at low frequencies is lower, because we need a higher frequency resolution there and sadly can't have both at the same time.

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