How to get GetSpectrumData of an audioClip before playing it?

Is there a way to get fourier data of an audio clip before playing it using AudioSource.GetSpectrumData?

Edit: If not then how would one try to accomplish such task?

You want the Fourier Data?

GetSpectrumData, is a FFT spectrum analysis of the sound.

you can’t get an FFT analysis without doing an FFT analysis!

When you run that function it just gives you an array of amplitudes of frequencies, have to see some examples but thats what it should do.

I had the similar challenge and ended up with 2 audio sources. The first one would start playing in the beginning of the scene but with volume=0, I would take the FFT from it and process as necessary. The second audio (with the same audioClip attached) with volume=1 would start playing after 3-5 seconds.