Re: making a sound unrecognizable (the satanic trick)

[Brian Gygi <bgygi@xxxxxxxxx>]

Hi Massimo

Actually, I did a study on identifiability of time reversed sounds 
(presented at the 2004 ARO) in which I found that time reversal was only 
good at obscuring very short sounds, such as an axe chopping.  Longer 
sounds, such as a tree falling and baby crying were barely affected at 
all.  I think that longer sounds are more robust because of the 
the long term spectral structure.  Most shorter sounds have broad band 
spectra so the only cues available are temporal.

Best

Brian

On Wed, 13 Sep 2006, Massimo Grassi wrote:

> 
> a good way to make a sound unrecognisable is to play it backward in  
> time (see for example, the ASA demo cd). Acoustics parameters are  
> untouched (although time reversed). It might not work for amplitude  
> steady sounds (e.g. a food blender).
> 
> Ciao,
> m
> ********************
> Massimo Grassi - PhD
> Laboratorio di Psicologia
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