Swampdog, Try some absorbtion at the first reflection points along the side wall and ceiling, if possable try some on the back wall also. Sibilence can also be caused from the high frequencies bouncing around the room.
sibilence....any cures out there?
I have recently accuired a pair of Nola Viper 1A speakers, while their performence is outstanding generally, the only problem is highlighted sibilence on vocals which is very annoying!!! Is this down to the speakers? Would a change of interconnects help? Any ideas from you guys would be appreciated greatly...