----- Original Message -----
From: Mathieu Bouchard matju@artengine.ca To: Ed Kelly morph_2016@yahoo.co.uk Cc: PD List pd-list@iem.at Sent: Monday, August 29, 2011 8:04 PM Subject: Re: [PD] making puredata headphone-safe
On Mon, 29 Aug 2011, Ed Kelly wrote:
The problem is that some objects can generate unstable errors that are
orders of magnitude greater than normal audio signals. Then there is a signal that maybe goes between +/- 100000 rather than +/- 1, and the volume control makes little difference.
It's much, much worse than that. If you have anything that multiplies the amplitude of the signal by 1.0001 at every sample, the amplitude gets 82 times louder every 44100 samples, and it will go beyond 8e+37 and rounded to infinity, where no multiplication by a fraction can possibly fix it.
So why not always have [clip~ -1 1] before and/or after your pd master volume control? Could the distortion resulting from clipping out of range values possibly result in a signal anywhere near as loud as what you're describing? Or would adjusting the
master volume to an acceptable level for the loudest possible clipped sound result in too
small a dynamic range?
-Jonathan
that's quite a few billion billion billion.
It's easy to get there. Put the wrong number in [*~] in a delay-loop, or put the wrong number in [rpole~], ...
| Mathieu Bouchard ---- tél: +1.514.383.3801 ---- Villeray, Montréal, QC
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