Re: Granular synthesis and auditory segmentation

["Richard J. Fabbri" <fabbri@xxxxxxxxxxx>]

Bob,

>  I'm not sure that I see how an MAA of 1-2 degrees (the 10
>microsecond resolution of the binaural system) is crucial to
>explaining the Cocktail Party Effect.  Has anyone ever done any
>cocktail party experiments with talkers separated by as little as 1
>degree?
        ... Maybe an absurd example would help to see why.

        ... What if our M(inimum)A(udible)A(ngle) were, instead of
        1-2 spatial degrees, actually much larger ... say, 100 degrees !

        ... i.e., TWO speakers would be perceived as ONE speaker
        unless they were separated by MORE THAN 100 degrees !!!

        ... MAA is simply a resolution limit from which derives our native
        ability to (eventually) separate SOURCE information streams.

        ... It is our ability to SEPARATE SOURCES that allows us to focus
        upon ("analyze") any PARTICULAR SOURCE.

        ... But, to answer your question more directly, yes, essentially
        moving the source by 1 -2 degrees is how MAA is measured, i.e.,
        Do you, the listener, perceive the source as having moved ?

        ... And, yes, an MAA test could be conceived that actually presents
        Source-Pairs with 1-2 degree SEPARATION and the listener then
        asked whether they hear TWO "distinct" voices.

        ... This is a bit like the distinction that was made between inertial
        and gravitational mass (they're identical !!!) before Einstein's
        Theory of Relativity.


Regards,
Rich Fabbri

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