The aim of auch (audio-checker) is to visualizeharmonics in musical recordings. Many tools showthe spectrum, but this tool focuses on one or twospecific octaves, with an indication of thetonica, sub-dominant(IV), and dominant(V). Thisway, notes, chords, and harmonics in a musicalpiece become clearer. It also supports other typesof transformation (like wavelets, surface waves,strings, resampling, etc). Another feature is thatthis tool can compare incoming and outgoing audioto test external filters.License: GNU General Public License (GPL)Changes:
This version adds surface waves to the tool. Bothtransformation and visualization of sound ondifferent surfaces (such as rectangle, circle,hexagon, and triangle) are supported. The resultsare known as "Chlandi patterns". The transformsupports both pre-recorded as live sound, so youcan have an open microphone visualizing sounds.The documentation gives you a how-to, someexamples, and a movie.

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