Auditory sound presentation

[David Hairston]

I can think of two ways to solve this offhand.
The most direct way would be to just edit your .wav files so that they
include they actually last exactly 4000 ms; on that 2500 ms stim, just
add 750 ms of silence to the beginning and end. You can do this in
GoldWave with about 2 clicks.
Another route to go would be add a Wait object before and after the
sound. In the primary List object, change the Wait duration according to
the stimulus sound length so that it all balances out. On any that need
no extra silence, just make the duration 0. *one note* - the actual
duration of the wait in these won't be 0, it will be 1 monitor refresh
rate, maybe 15 ms or so.



-----Original Message-----
From: eprime at mail.talkbank.org [mailto:eprime at mail.talkbank.org] On
Behalf Of Kate Dupuis
Sent: Wednesday, March 21, 2007 11:56 AM
To: eprime at mail.talkbank.org
Subject: Auditory sound presentation

Hello all

I have a problem concerning presenting sound files in my experiment.

The entire presentation time of each of my SoundOut objects is 4000
msec.
However, my stimuli are typically not exactly 4000 msec long, therefore
I
will have a period of silence before and after the stimulus. For
example,
if Sound 1 is only 2500 msec long, I will have to have 750 msec of
silence
before and after sound 1 is presented. If sound 2 is 3000 msec long, I
will have to have 500 msec of silence before and after it is presented.

The period of silence before and after the stimulus is played within
that
4000 msec period will vary according to the length of each stimulus. How
do I tell EPrime how many msec of silence to present on each trial? That
is my question.

Thank you,

Kate
-- 
Kate Dupuis M.A.
Ph.D. student
Human Communication Laboratory
Department of Psychology
University of Toronto at Mississauga