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How the cochlea computes (2024)

(www.dissonances.blog)
475 points izhak | 2 comments | 30 Oct 25 17:01 UTC | HN request time: 0s | source
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tryauuum ◴[30 Oct 25 17:32 UTC] No.45762674[source]▶
man I need to finally learn what a Fourier transform is
replies(7): >>45762759 #>>45762780 #>>45762781 #>>45762805 #>>45762824 #>>45763744 #>>45765427 #
CGMthrowaway ◴[30 Oct 25 17:44 UTC] No.45762824[source]▶
It's a Copy>Paste Special>Transpose on a waveform, converting Rows/Columns that are time/amplitude (with wavelength embedded) into Rows/Columns that are frequency/amplitude (for a snapshot in time).

People love to go on about how brilliant it is and they're probably right but that's how I understand it.

replies(1): >>45762876 #
TheOtherHobbes ◴[30 Oct 25 17:48 UTC] No.45762876[source]▶
Pretty much, but phase is also included. Which matters for some things.
replies(1): >>45763053 #
bobmcnamara ◴[30 Oct 25 18:03 UTC] No.45763053[source]▶
But mostly not for ears it turns out!

Phase matters for some wideband signals, but most folks struggle to tell apart audio from hilbert-90-degree-shifted-audio

replies(2): >>45763136 #>>45768011 #
1. xeonmc ◴[30 Oct 25 18:09 UTC] No.45763136{3}[source]▶
Phase is required if it is to be a reversible transform. Otherwise would just be a Functional.
replies(1): >>45768353 #
2. ◴[31 Oct 25 04:12 UTC] No.45768353[source]▶