audio playback with variable tempo

[Ian Smith]

In freebsd-questions Digest, Vol 445, Issue 4, Message: 12
On Wed, 12 Dec 2012 16:27:16 -0700 Gary Aitken <freebsd at dreamchaser.org> wrote:

 > Can anyone suggest an audio playback application that allows you to vary the
 > tempo?  I've used audacity on win systems, but I don't see that in ports.

You'll have found audacity by now, but audio/sox does that and a zillion 
other things (mixing, pitch bend, all sorts of filtering and effects ..) 
if you're happy working from commandline or scripts and can handle a 
HUGE man page that's pretty much a background to audio processing in 
general.  It's very fast and light, too, for recording or playback.

cheers, Ian