Surround Back?

[DaMonk]

I hoping for some feedback on selecting a surround back speaker
I am currently running a pair of FXi50 surrounds and would like to
add a surround back (one) the polk dealer I spoke with suggested
using a center channel,either a CSi20 or CSi30 as I do have limited mounting space. Another option is to consider a single
bookshelf type speaker such as a RT15i or RT25i which I'm not sure if You can buy just one should that be the best choice. Anyone have other suggestions I'm open. Also Mounting location tips thanks

[mantis]

OK,
using one speaker is fine,I'm not sure why you want 2 use just one.
What is your room like and I can guide you down the path of rear speaker placement......And how to install them.
Input man Input...need Input........

[GuitarheadCA]

Mantis, I can't figure out whether you're saying:

I'm not sure why you want two, use just one (in favor of 6.1)
or
I'm not sure why you want to use just one. (in favor of 7.1)

Anyways, DaMonk, The best speaker to match with the FXi50's would be the CSi40. If space is an issue, the CSi30 is pretty close,or if you want a bookshelf speaker: the RTi38 or RTi28. The RT25i and 15i both have different tweeters than your side speakers and would not be the best match.

[mantis]

GuitarheadCa,
what I'm saying is I'm not sure why you only want to use 1 surround back channel.If the preamp or receiver he is using supports 2 channel,Id use both.But if he is going to use a center speaker for the surround back I can see just suing one.
The rti series bookshelf speakers should work just fine.

[Frank Z]

I've got a CS175 that i'm not using anymore if anyone is interested