Author Topic: THD measurement  (Read 3569 times)

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geadinc

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THD measurement
« on: August 11, 2015, 03:09:33 PM »
I've been asked to optimize a compressor/limiter for a client and I need to check the THD response and minimize it. It's not clear to me that SignalScope Pro would work for me or not. Could someone tell me if it does a reasonable job of measuring THD between input and output of a device?

FaberAST

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Re: THD measurement
« Reply #1 on: August 13, 2015, 10:24:41 AM »
SignalScope Pro's FFT Analyzer tool is capable of computing THD with up to 15 harmonics.
In order to get good results, you'll need to use a test signal that's at a frequency that matches one of the frequency bins in the FFT. This is fairly simple if you use SignalScope Pro's built-in signal generator and use the same audio device for both output and input in your measurements.

geadinc

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Re: THD measurement
« Reply #2 on: August 13, 2015, 02:41:47 PM »
Cool, thanks! I'll be using a Presonus Firestudio Mobile to give me the XLR in and out.

brianf7408

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Re: THD measurement
« Reply #3 on: October 16, 2015, 01:21:48 PM »
Am I correct in assuming that the number of spectral lines is equivalent to the number of bins?

FaberAST

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Re: THD measurement
« Reply #4 on: October 16, 2015, 01:43:00 PM »
Quote
Am I correct in assuming that the number of spectral lines is equivalent to the number of bins?
Yes. Each line represents one bin.