[PD] db to phon conversion

[day five]

Hello Alexandre,

There is an instructive figure on the Wikipedia page for "Equal-loudness
contours."
https://en.wikipedia.org/wiki/Equal-loudness_contour#/media/File:Lindos1.svg

This shows dB SPL (re: 0 uPa) by frequency for a pure tone / sinewave
input. If you want to convert a given dB SPL to its phon level you should
take care to ensure that your filter weighting matches with your norm
reference for phon level (i.e. A-weighting etc etc however the phons were
obtained). See also ISO 226.

Interpolation between phon levels is likely not linear as well. Note that
phon levels are a perceptual based scale of "loudness," which itself is the
perceptual correlate of sound intensity (a physical measurable quantity in
air, typically dB SPL.)

Because this unit is perceptually based, and is predicated using pure tone
presentations at 1 kHz, you will get different results: 1) when using third
octave or smaller bands (due to critical bands in hearing and nerve signal
summation at the brainsteam and cortex), and 2) with time varying or
modulated signals (such as the ISTS).

./d5

On Tue, May 28, 2019 at 12:22 PM Alexandre Torres Porres <porres at gmail.com>
wrote:

> just to be clear,  I meant convert from dB to phon by also having a pure
> tone frequency as the input
>
> Em ter, 28 de mai de 2019 às 14:02, Alexandre Torres Porres <
> porres at gmail.com> escreveu:
>
>> Hi people, I'm looking for an online resource or some piece of software
>> that would allow me to convert intensity levels in db to perceived loudness
>> in phons... anyone?
>> cheers
>>
> _______________________________________________
> Pd-list at lists.iem.at mailing list
> UNSUBSCRIBE and account-management ->
> https://lists.puredata.info/listinfo/pd-list
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.puredata.info/pipermail/pd-list/attachments/20190528/b44ef618/attachment.html>