I've been digging around, trying to get a definition of what "kind" of speaker the Klipsch Synergy and Reference series of surrounds actually are. Bi-polar or di-polar?

According to Klipsch, something they don't advertise, is these speakers are referred to as "WDST" (I can't remember the exact phraseology, but it's something like Wide Dispersion System Technology). Anyway, they claim that a key reason these speakers work so well for both music and movies is that the combine the best elements of both di- and bi-polars,and they do this without being out-of-phase.

I'm interested in learning more. ... Mike

They aren't either of those. They are closest to monopolar, it's just that the tweeters are at a 40 or 45 deg angle to disperse better.

Bi and dipoles means they have poles, opposites, drivers facing 180 deg from each other. Klipsch doesn't have that.

I have the RC-3s. They sound great and make placement on the side a little easier. The speaker can be just forward or just back of the sitting position and still sound the same.

Wide Dispersion Surround Technology... that was it.

Hey, Spiky. Yep, they are neither, but they sound like both! Localized and directional.

I have the RB-5 bookshelves for mains, the SC-1 centre, SS-1 and SS-5 for surrounds and rears.

Pretty nice, aren't they? But wait: the RC-3 is a Centre channel, is it not? Did you mean RS-3? that's what I really wanted, but given the size of my living room and the WAF, they are just too large. Maybe when I hang the ones I've got, she'll get used to their presence and then I can upgrade... ;-) ... Mike

Yeah, your right, mental glitch. I actually have 1 RC-3 and 1 pair RS-3s. Looking at RF-3 for my mains soon. Or maybe the new RF-5. :)

If you have to, find a store with the RS-7s and the RS-3s. Show the comparison, ignoring the size of the SS series. Maybe that will work. But the RC is MUCH bigger than the SC, that could be tougher, but is also more important for smooth sound.

I hate that whole WAF deal....

The RS-7s are a tad out of my price range, fer shure, dude. And bigger than what I can take. But, since I moved up quite a bit higher than what I had, I'm having some serious enjoyment here... ... Mike

The angle of the speakers gives some of the "ambience" of "-pole" speakers which are created to bounce off the nearby walls, etc.=, but they are not out of phase, which makes them closer to "monopole" speakers.

Di-pole=oppposite poles=out of phase.
Bi-pole=opposite poles=in phase.
Bi-pole/di-pole (my Paradigm's)=opposite poles=out of phase above 250hz and in-phase above 250hz. The idea being not to cancel out the lower frequencies by being in phase.

... Greg

I have absolutely nothing useful or entertaining to add to this thread. I'm just testing the bold/italic tips from the pronto forum over here in the slower lane.

[Link: remotecentral.com]

As the happy owner of a Definitive Technology system, which, except for the center speaker, are bi-polar, I'd like to add my 2 cents' worth:

Mono-polar simply refers to a typical speaker system that has only front-firing drivers, all normally driven in phase, which means that all diaphragms (cones or domes) move outward (toward listening space), which causes compression of the air, and inward (away from listening space), which causes rarification, simultaneously.

Di-polar means that there are two sets of drivers, although not necessarily identical, facing away from each other, that move out of phase, which means that, while diaphragms on one side of the cabinet (box) move outward, those on the other side move inward. Note that the two sides, or faces, of the cabinet need not be exactly opposite, or parallel, from each other; the box can be trapezoid shaped. (Planar speakers, such as Magnepans, also exhibit this phenomenon.) The result of a di-polar speaker is that sounds from the two faces tend to cancel each other, because one driver(s) is causing compression, while the other(s) is causing rarefication. The supposed advantage of this type of system in a surround system is that, because of the cancellation, it is more difficult to pinpoint the source of the sound.

A speaker front panel is also called the baffle, because one of its purposes is to prevent the front sound wave from being cancelled, or weakened, by the rear sound wave. A wall, with dimensions larger than the lowest wavelength desired, can also fulfill this purpose; years ago, budding audiophiles actually mounted speaker drivers in walls or doors!

As a side note, this is why speaker cabinet construction is such an art. A sealed speaker, one type of infinite baffle, uses the air trapped inside the box to limit woofer travel; this is known as "acoustic suspension", made popular years ago by Acoustic Research. A sealed enclosure tends to be less efficient, meaning less loudness per watt, but as long as the power is available, produces the smoothest, deepest bass, and the cabinet can maintain control of cone movement even below the driver's natural resonance. (All speakers have a frequency at which they move most easily; in fact, this applies to all materials.) Try tapping gently on a woofer cone sometime; the 'thump' you hear is at the resonant frequency of the driver - in the box it's in; it will be different in free air.

The vented enclosure, by the way, uses one of several tube shapes, known as 'ports', to use the rear sound wave to reinforce the front wave, rather than weakening it, because the port length, diameter, and shape are calculated to delay the rear wave long enough to compress the air at the same time as the front wave, rathe than cancelling it. The difficulty with this method is that, although this usually increases the efficiency, or loudness per watt, of the system, the boost tends to gather around a reletively narrow frequency range, and the enclosure provides little control of the cone movement below the system resonance. Ever hear very loud car stereos? Sure, it's loud, but all the bass tends to be around one note. Hardly "high fidelity".

Finally, there is bi-polar, which is where the front and rear drivers move in phase, compressing and rarefying the air simultaneously. Note that this tends to radiate, or propagate, sound most like real musical instruments, or most sources of sound, even with surround systems. Think a bomb causes rarefication on one side of the explosion, or compression all the way around? Also, discrete surround soundtracks are mixed using, and to be used with, directional speakers, not non-directional ones. Maybe in the "old days" of Dolby Surround, with the mono surround channel, it was important to not be able to pinpoint the sound source, but why have stereo surround channels (2, 3, or more) just to have the directivity intentionally muddled?

I guess my 2 cents' worth became a couple of bucks, but I hope this explained a bit to those interested.

Larry

agreed....direct radiating speakers are really the way to go with todays DTS and 5.1 material!!!

Wow, Larry, a very impressive explanation: clear and concise. You kind of said in a nutshell what many lengthy magazine and book articles have only been able to obfuscate. Thanks from all of us; I like this site.

Matt: I would disagree that "direct radiating only" is the way to go. I've spent a good deal of time listening to various types now, and I definitely favour the spatial advantages I notice with the Klipsch. In fact, it is almost as noticeable going from direct radiating to "whatever these are", as was going from ProLogic to DD5.1 and DTS. IMHO... ... Mike

I just bought a full set 2 front, center, 2 rear, and the 10" SW. GREAT SOUND!!!! The whole place shakes.

Have them to the home theater system I just installed.
Mitsubishi X400 projector, Onyko tuner/amp, Pioneer DVD. Should have done this long ago.

Don: which speakers?

THX and Dolby (I think) both recommend dipolar side surround speakers for their surround systems. The point of the surround part of your theater (meaning not the LCR speakers) is to have diffuse sound that highlights/amplifys/relocates specific sounds coming from the LCR speakers. Dipolar is very good at this. Although DD and DTS now have discrete surround modes, the producers still seem to use them for highlighting the main speakers more than just locating noise (like a flyover) that is supposed to come from behind the listener. So this is why so many like dipolar.

Actually, I think they also recommend monopolar (direct radiating) speakers be in the corners, rather than directly to the side for optimum placement. Your room may vary, of course.

I suppose THX would recommend di-polar, they came up with it.

IMHO, direct radiating speakers use the DTS and 5.1 encoding methods to their fullest, by giving you truly 360 degree sound capabilities. Although, for the mono rears of pro-logic, I see the advantage of a diffuse soundstage.

I guess it's all to the listener, buy a speaker with swithable modes solves all the probs. And yes I would never place a monopole, so to speak, on a side wall, it would have to be place behind the listener. If you have no rear wall, you have no choice, go with the other method.