D&Dtools1

Your voice is amplified greatly.
Subtract 10 from the DC of Listen checks made to hear you talking (even whispering).
You also gain a +2 competence bonus on Intimidate checks.
While this spell is active, you can use a swift action to create a 15-foot-long cone-shaped burst of intense sound with a shout.
Every creature in the area takes 1d8 points of sonic damage and must succeed on a Fortitude save to avoid being stunned for 1 round.
Doing this discharges the spell.
Creatures that cannot hear are not stunned but are still damaged.