the flashback sound effect

[hakkomielteinen]

the sound effect you get when you hear voices in flashback
can be achieved with backward echo or reverb
you can download the example below

[Kurton]

I've played around with this before, too. Though myself lacking any knowhow of "real" sound editing, I just placed two slightly offset samples in Reason, one with "Reverse Space" reverb on, and one without. :p

I bet the method you're using is far easier, though. What do you use?

[hakkomielteinen]

just make it backward then apply echo or reverb then make again it backwards