[PD] limiter questions

Mathieu Bouchard matju at artengine.ca
Wed Aug 26 23:57:29 CEST 2009

On Wed, 26 Aug 2009, Derek Holzer wrote:

> Too reiterate, try translating the values you put into your patch 
> between dB and RMS. dB is logarithmic while RMS is linear,

dB is a unit of measurement. RMS is a thing you can measure. If you are 
applying [rmstodb] on a RMS linear amplitude, you get a value in RMS dB, 
whereas if you are applying [rmstodb] on a peak linear amplitude, you get 
a value in peak dB. However, the vocabulary used for Pd in this case 
confuses the concepts and says "rms" to mean "linear amplitude" regardless 
of whether it's "rms", "peak", "effective", or any other variation on how 
the unit is used.

> Where the author has written "power", think RMS.

So why wouldn't power be the square of linear amplitude instead, as it 
usually is?... that is, MS, which is RMS without the R... (this also goes 
with how [dbtopow] and [powtodb] work)

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| Mathieu Bouchard, Montréal, Québec. téléphone: +1.514.383.3801

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