Audio oscillator and Spectrum


I have just started to dig into the audio chops.

One odd thing I noticed, when I send a sine wave with base frequency 440 hz from the audio oscillator to the audio spectrum for frequency visualization, I get a spike around 10k. My audio spectrum chop is set to Visualizaiton, Freq->Log scaling at 1, Match length to frequency, and I have the viewer display unit set to samples.

In theory, the fundamental should be at 440, no? Is my display setting off or something?

Please let me know.
Thank you.

If you look at the Info pop-up for that Audio Spectrum CHOP node (MMB on node), it says

Set “Frequency <-> Logarithmic Scaling” to 0, then multiply any sample to 1.000 to get the Frequency at that sample.

I see the spike at sample 440.

Sorry it’s documented there… that 1.000 depends on sample rates etc, so it’s not a constant.

I added that tip to the wiki page for Audio Spectrum.

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