"presence" channels

[rolyasm]

I see some high-end receivers having 9.1 or higher channel ratings and I wonder how this works. Are you using the extra 2 channels as surrounds for larger, multi-seating areas, like one seat behind the other? Also, what is a "presence" channel? I see some people debating whether to use the two channels as surrounds or presence. Any enlightenment would be great. Thanks
Roly

 

[Doug917]

"Presence" channels are used by Yamaha. They are supposed to be mounted above the Left/Right channels and further out to the sides. They are only engaged when using Yamaha's proprietary soundfields and increase the sense of spaciousness in the front soundfield.

Other companies such as Denon will let you connect two sets of rear surrounds (one for music and one for movies).

Several preamps use what they call side-axis channels which are quite similar to presence channels. A couple Parasound pre/pro units even let you design what and where you want to use 2 extra channels for.