====== Testtonen ======

https://forum.xojo.com/30275-sound-generator/0

https://developer.apple.com/documentation/avfoundation/audio_track_engineering

https://www.blackcatsystems.com/software/audio-function-generator-software.html

www.nch.com.au/tonegen/index.html

==== Terts ====


[[https://nl.wikipedia.org/wiki/Resolutie_(geluidsmeting)#Tertsbanden_of_1/3_octaafbanden]]
https://www.engineeringtoolbox.com/octave-bands-frequency-limits-d_1602.html

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