I am working on an application of SoX that I want to include a trim
effect but have been unable to figure out the syntax with this case. 
The command line (in a shell script) without the trim is:

sox "$1" -t wav - -- | aplay

I have tried adding trim $offset offset various places and get errors
for each, although the errors vary.  What is the appropriate place for
me to put trim $offset in this command line?  In case it matters this is
SoX v14.4.1 and it is a binary on a platform for which I cannot provide
an alternative version.

Dave