[ctviggen]

Well, my original goal was to get Salk point-source surrounds to go along with HT-3s and matching HTC, but the costs would be prohibitive.  So, I'm thinking of something like these for the surrounds:

http://www.axiomaudio.com/qs8.html

or

http://emotiva.com/erd1.shtm

The Axioms are bipoles, but with an interesting design where the woofers and midrange fire up and down.  The Emotiva can be Left/Right Bipole, 2. Left Dipole, Right Dipole, or Left/Right Inverted Dipole.  That sounds interesting to me, as I'm unsure of placement of these and it might be fun to play around with the settings.

Has anyone used bi/dipole speakers in a surround setup?  I'm mainly interested in movies, although some music DVDs will be played.  I also have a large enough room that I want to put in two sets of these speakers.  Anyone use 2 sets of bi/dipole speakers for surrounds?

I've used point-source type speakers for surrounds, so I'm wondering what other's opinions are of the bi/dipole versus point-source debate.  I plan on trying these out, but my room is currently under construction and I might not be able to try them until the room is completed. 

[Big Red Machine]

I now prefer direct radiating to dipoles in 7.1.  I like the sound coming directly out from a full range surround versus the difuse nature of the dipoles.  I crossover at 50 hz-ish.

If constructing the room leave enough room for full range speakers up to 45" tall to fit in columns so you can go crazy later on.

[ted_b]

Yes and No.  I use dipoles for my movie surrounds (7.1, so sides and rears) and have for many many years (Logic7 supported 7.1 almost 20 yrs ago).  I also use direct radiators, identical full-range drivers to my fronts, and use them in an ITU 5.1 setup strictly for hirez surround music listening (both sets of surrounds, i.e all six of them, are never on at the same time, only 4 dipoles or 2 music surrounds).  I did this for a couple reasons, the main being that I didn't want to cannibalize the 7.1 setup when i got the later 5.1 hirez itch, and I wanted my music surrounds at the ITU 20 degree position (plus I had the luxury of having the room, and a dedicated space).  As i said, the dipole decision was 20 yrs ago and for movies, even later Dolby Digital discrete and now the newer lossless truly full-range TrueHD and DTS HD MA, the more diffuse nature of the dipoles doesn't hurt me for movies, especially for the folks in the second row.  They retain a surround feel.   However, depending how you have the setup, and depending on what percentage of listening is surround music I would go with direct radiators.  I mean, you're gonna place them side and rear anyway so the envelopment you'd get with dipoles are taken care of by the sheer number of speakers placed in the rear semicircle, and for music you could turn off the sides or place them slightly behind absolute 90 degree side. 

I wouldn't sweat it.  The dipoles you've narrowed down to are nice speakers.  I'd be cognizant of timbre and tonal matching the fronts too, though.  Don't choose a speaker set that doesn't tonally match the Salks.

[JP78]

Has anyone used bi/dipole speakers in a surround setup?  I'm mainly interested in movies, although some music DVDs will be played.  I also have a large enough room that I want to put in two sets of these speakers.  Anyone use 2 sets of bi/dipole speakers for surrounds?

ctviggen - i work at a company that designs several home theaters a year.  around here, the engineer pretty much says that if you're going 100% movies with the surround usage then the quality is largely insignificant (above home-theater-in-a-box of course).  the surrounds in movies are for directional cues and ambient effects. certainly the quality does make some difference, but for surrounds the effects of diminishing returns are far greater than the front mains or surrounds.

also, a diffuse surround sound is is often preferred for a much wider sweet spot. if you look strictly at the specs of the dd7.1 or dts-ex format, both spec bi/dipole for side surrounds and direct radiating for rears. in practice, however, 95% of people that have home theaters (either dedicated theater or mixed use room) prefer bi/dipole for all four surround channels for the wide sweet spot the whole family can enjoy.

of course, for music you have a whole different set of requirements which i'm sure you're aware of. dvd-a and sacd specify identical speakers for all five or seven channels. in multichannel music discs, timbre matching is *much* more important.  yes, these multichannel requirements of movies and music are in direct contradiction to each other, and as the consumer it's pretty frustrating. short of going with seven salk ht-3's in your case, (a dream i'm sure but impossible for 99.9% of us)  you may want to contemplate going with inexpensive bipole surrounds, as well as inexpensive direct radiating speakers, and using a speaker selector to switch between the sets depending on your source material.  i would also second bigredmachine; if you can then you should fit in some wall soffits for floorstanders, you seem like the type of perfectionist who may take advantage of the space later .

good luck,