Quote:
Originally Posted by
RCChris 
Sorry for the hijack, but I have a similar issue and stands won't work. My surrounds are about 3' behind the primary listening location at approximately 125-130 degrees and about 2' above ears. They are not dipoles. A couple questions.
1. Should I aim them down and in (toward primary listening location) or straight out, etc.
2. I have a spare center lying around. Would I benefit from placing it between the two?
Thank you,
Chris
1--aiming the speakers. Most speakers do not radiate equally at all frequencies and in all directions. Most are designed to sound best if the tweeter is aimed at the listener's ear. Most have the widest good response in a horizontal arc. Counter intuitively the vertical speaker driver array, tweeter over mid over woofer, has a wider (parallel to the floor) flat response than the same speaker lying on its side. So most speakers have a sound their best if your ear is about at the same level as the tweeter and you are at or near the center extended center the projected center of the tweeter. This is the reason you tow the mains in toward the primary listening position.
Surround channels however are by design intended to be a bit diffuse -- Dolby labs puts it this way-
"Ideally, your front speakers, high-frequency drivers, or tweeters should be positioned at ear level (when you're seated). Our recommended height for the surrounds is above ear level, as soundtracks are likely to be optimized for that location." (emphasis added)
So if your arrangement is flexible you might try aiming the surrounds. It might make an improvement. My own layout has two smallish full range towers as surrounds, and two small speakers on stands a bit higher than the towers and tilted up (effectively aimed above ear level) for the rears. So I have two below and two above.
I really cannot tell the difference.
2-spare center- If you have a 6.1 system the rear channel is mono so you could add a third speaker. All the diagrams show two (spacing varies) but I will bet that one will work in some way for you.
There is no useful way to create a third channel from the L/R surrounds by just adding
a speaker. There are posters who seem to have doubled up on each side and been happy with the result. If you do that take care with impedance. You would effectively be recreating quasi dipoles, and would want to try running the speakers both in and out of phase.