How can I get this Vocal effect???

[xmortumx]

Hey guys Well im doing this bands demo and i was wondering what can I do to get this vocal effect



at 2:00

or like in Slayer-Angel of death at :30 right before the vocals come in it makes this effect.. any clue on how i can get it.. is it Delay?? or like vocals played backwards??

 

[ahjteam]

choose a clip, invert, add delay and reverb, print, re-invert