Hello,
I am building my first dedicated HT in my basement (dedicated room). Just purchased Optoma HD20 and Onkyo 806 receiver. I will be using set of existing speakers by Sound Dynamics
I have:
2x rts-11 for the front
2x rts-7 for the surround
2x RTS-rs1 (http://www.audiocircuit.com/index.php?c=SPZ&m=RTSRS-1)
1 x RTS-C2 center speaker
1 x their sub (dont remember the model #)

As you see, I have 2 sets of speakers for side/back surround.
As per THX recommendation, I was planning to use RTS-RS1 as side surround speakers and pair of rts-7 as back surround speakers. However, since some of the material will only be played in 5.1 I am wondering if I should have my side speakers of better quality (rts-7)? Otherwise, I will endup always using the bi-polars (rts-rs1) which are not in pair with the rest of the system and the full size good rts-7s will only be used with 7.1.
Any suggestions will be greatly appreciated.
Thanks,
Wojtek

I would use whichever set is better sonically matched to the mains as the side surrounds. For the reason that you mentioned: when using 5.1, if you don't matrix it to 7.1, you will not even be using the rear surrounds.

However, if you can, try both and see what you like better. You may like using the bi-polars as sides, especially if they are closer to you than the rears on your setup, because they may be less localizeable.

It's really up to your ears to decide. But the RS1 will be good for your side speakers- I prefer the **pole speaker to be on the side close to ear level..