💾 Archived View for thrig.me › blog › 2023 › 09 › 21 › pitch-hallucination.gmi captured on 2024-08-18 at 18:04:16. Gemini links have been rewritten to link to archived content

View Raw

More Information

⬅️ Previous capture (2023-11-14)

-=-=-=-=-=-=-

Pitch Hallucination

Pitch hallucination? What could that be? The claim here is that one does not actually hear musical pitches; what is actually going on is that the basilar membrane is lit up by various frequencies, and only after some postprocessing does the pitch hallucination department present its findings to the central committee (which, in turn, some claim is hallucinated as "I" or "me").

Anyways, for those with functional or mostly functional human ears to you the following files may exhibit the hallucination.

beee1.mp3

beee2.mp3

Are these the same pitch? The difference here is that one totally omits the fundamental frequency of 245.88 Hertz (which is pretty close to the B below middle C assuming A440 tuning); odd harmonics are represented though both include the second harmonic at 491.76 Hertz.

    $ perl -E 'say $_, "\t", $_ * 245.88 for 1..9'
    1       245.88
    2       491.76
    3       737.64
    4       983.52
    5       1229.4
    6       1475.28
    7       1721.16
    8       1967.04
    9       2212.92
    $ atonal-util freq2pitch 245.88
    245.88  b       -1.06   0.43%

Someone better at this could probably better forge the appropriate volume for the various harmonics. Other things to experiment with would be to see how much error is tolerated before harmonics start being heard as some other pitch or "dunno" noise. Or how much can the harmonics (or worse, partials) be messed around with without changing the pitch that is summoned from the Platonic Plane of Perfect Pitches?

Reference

"Voice Leading", David Huron. 2016.

https://mitpress.mit.edu/9780262537384/voice-leading/

In theory there's a website with samples but they neglected to put the URL in the preface and instead claimed that a web search for the phrase "voice leading demonstrations" would find the goods. Google spams a bunch of youtube links, and duckduckgo turned up miscellaneous links before veering off into "Intel Introduces Thunderbolt 5 Connectivity Standard" and "Chinese officials voice faith in economy and keep interest rates steady".