Why dipoles?

[FNG212]

I don't really understand why rear/surround (or are they not synonymous?) speakers are often smaller than the fronts. I get that most action/noise comes from the screen therefore the front of the viewing stage but why not have the same speakers in the rear for when stuff is off camera?

To this end, why are dipoles favored over bookshelf designs? Do they disperse sound more efficiently due to the multi-axis faces?

Thanks.

 

[fredk]

I suspect that dipole/quadpole speakers work better in a wider range of rooms (because they disperse sound more effectively). Most people don't have the luxury of purpose built theaters.

Cost would be the other factor. If I had to drop 1k+ per surround I would have stuck with two channel.

From what I understand, the best setup is using 5/7 identical speakers.

 

[lsiberian]

I don't really understand why rear/surround (or are they not synonymous?) speakers are often smaller than the fronts. I get that most action/noise comes from the screen therefore the front of the viewing stage but why not have the same speakers in the rear for when stuff is off camera?

To this end, why are dipoles favored over bookshelf designs? Do they disperse sound more efficiently due to the multi-axis faces?

Thanks.

The reason for using smaller surrounds is for asethetics, and WAF.

The reason for using dipoles is for eliminating localization of surround effects. Essentially by using dipoles you are more immersed in the surround sound experience.

Tweeter matching is the most essential for sound stage. Midrange speaker type is helpful to match. However when it comes to ideals. I think different channels have different ideals. A coaxial for example often makes a superior center channel while non coaxial often makes better LR channels. Dipoles make great surrounds. Of course the only way one can really be ideal is by building their own speakers.

 

[jostenmeat]

I don't really understand why rear/surround (or are they not synonymous?) speakers are often smaller than the fronts. I get that most action/noise comes from the screen therefore the front of the viewing stage but why not have the same speakers in the rear for when stuff is off camera?

Cost, aesthetics, and ability to mount high enough to fire over blocking furniture and seat backs. I've seen theaters with tower surround speakers, sitting atop risers to fire over seat backs. You can imagine how unsexy that is to some people.

To this end, why are dipoles favored over bookshelf designs? Do they disperse sound more efficiently due to the multi-axis faces?

They aren't really. If they are ever favored, it's simply due to personal preference. Monopoles are totally fine enough as all of the ambient cues are embedded already in the soundtracks themselves. I did recently change to bipolar side surround for greater coverage between two rows, but honestly, the improvement is subtle at best, IMO. I did, OTOH, lose some extension, and I think it's easy enough to notice, but not a biggie... it's just surround. Focus on the front stage, most definitely. If you can do an upright identical speaker as your mains, on the same plane, you already did great in my book.

Bipolar type speakers will depend more on boundary interaction than monopoles, so I think the latter will be more easily implemented in most rooms. Dipoles have drivers firing out of phase, and are designed so that you are sitting in the null.

 

[Sounds Good]

i wish more speaker builders made di/bi poles.... i personaly think that the have a VERY high WAF... (hint hint... ascend...)

 

[svartgotik]

Probably not a "true" dipole, i have Klipsch SS.5's, and because of my apartment layout, I have them mounted about 6 feet higher and 70degrees forward of listening position. I think the horn shooting essentially behind my ear and reflecting helps in this instance. Not really my choice for speaker placement, but architects here that design apartment buildings really don't care about THX placement specs.

 

[Sounds Good]

architects here that design apartment buildings really don't care about THX specs.

wouldnt that be nice if they did... and audiophiles apartment complex... mmmmm

 

[tbergman]

wouldnt that be nice if they did... and audiophiles apartment complex... mmmmm

I don't know about that, they better get some good sound dampening as well. I don't think I could live with SVS Ultras and Infinity Kappa builds on every side of my apartment.

 

[just-some-guy]

and ability to mount high enough to fire over blocking furniture and seat backs. I've seen theaters with tower surround speakers, sitting atop risers to fire over seat backs. You can imagine how unsexy that is to some people.

................................

Bipolar type speakers will depend more on boundary interaction than monopoles, so I think the latter will be more easily implemented in most rooms.

like this ? lol. my old mains.

.......................

could you elaborate on this for my room ? as i am thinking about bipolars
i have never heard bi/di-polars. so idk what to expect.

thanx

 

[just-some-guy]

ooops ............

 

[jostenmeat]

like this ? lol. my old mains.

.......................

could you elaborate on this for my room ? as i am thinking about bipolars
i have never heard bi/di-polars. so idk what to expect.

thanx

I guess I was implying that your best chances would be having your setup be symmetrical, in a room that is symmetrical in of itself. If you have that large opening on one side, but not the other, you may not get the best benefits of the design. Sure, symmetrical room is good for any setup, but since bipoles depend even more than monopoles on the boundaries, this is my perception. Now, my room is asymmetrical, and I still dropped the coin on bipoles, but I have two rows, and wanted to see how much extra coverage I got. Yeah, I guess I got a tad, but it wasn't nearly as much as I was hoping for. Just my initial impressions anyways.

ooops ............

Yeah, sure like that, heh. Though it seems awfully high. Turning the speaker upside down means tweeter is too low, but I would probably try a lower "riser" if one was available. If only for experimentation.


The main issue/point I have with these different surround designs is how much they cost. Sure if your fronts/center are worth $$$$$, then dropping $500-1000 on a pair of surrounds doesn't seem too bad. But, I will never recommend spending that much on surround duties if that forces any sacrifice in choice of the front 3, or the sub(s). Or display. Or most anything else! Monopoles work fine, especially if you just have one main LP.

 

[just-some-guy]

i hope i'm not jacking this thead, but it is on topic...... anyway.

i believe i have a symmetrical room. 12x19x8. but i do have a 6 1/2'x7 opening on my left, and a hallway on the right. i would hang the sides right about where you see my towers now, tweeter height. as it is now, i plan to build my sides/rears. perhaps with the RB kits. i am thinking to put 1 kit per side. aiming each channel about 30 degrees. it would be kinda like a pair of speakers right next to each other. did i say that correctly ?

i can't lower the tower surrounds down. as the left one would then blast my wife right in the ear. up higher aims it over her.

btw : dig my new chairs

 

[just-some-guy]

ya know, i was just thinkin. i do that sometimes.

i have a pair of BOSTON HD5's , they are small bookshelves. could i put em up there ..... heck, how about a pic. brb...

 

[just-some-guy]

like this, just to see how they would sound. they are 8 ohm, 2 would be 4 0hm. is this an issue ? i'm thinkin no. or could i wire them for 8 ohm, how ?

 

[jostenmeat]

like this, just to see how they would sound. they are 8 ohm, 2 would be 4 0hm. is this an issue ? i'm thinkin no. or could i wire them for 8 ohm, how ?

It's not recommended, but my guess is if the volumes are only ever moderate, then you might be ok. You need to research your receiver, and its amp section. I guess don't do it until you've researched the receiver's amp. Some cry uncle real quick with lower impedance, and others are much more robust.

As for two monopoles making one bipole, I've no idea what happens. Sorry. I hope someone who knows more will soon chime in for you.

 

[just-some-guy]

moderate ? lol. i play it as loud as the wife will let me. -15 to -10 usually. i'm thinkin that since i am not using the reciever front amps, then the rears would be ok. idk.

 

[jostenmeat]

moderate ? lol. i play it as loud as the wife will let me. -15 to -10 usually. i'm thinkin that since i am not using the reciever front amps, then the rears would be ok. idk.

I wouldn't do it. As PENG has pointed out, even if your power supply is being less taxed with your kind of setup, the amplifiers themselves can be too limited anyhow to take advantage of the power supply's remaining capability.

It seems that you're going to go nuts thinking about this. So... I say just get a pair of switchable bipole/dipoles, and then try both. I'm saying this, because I also went nuts thinking about it forever, and finally did it. Just get it over with! But, I also say this with the caveat that you are totally fine with everything else in your system. Room treatments possible?

The Axioms are kinda neat in that they are quadpolar. The high end PSBs are neat in that not only can they be set to dipole or bipole, but there are two sets of binding posts to allow, um, dual monopoles.

Lastly, since you really seem to love your surround, Audyssey just put this up on their site a couple of days ago. DSX 9.1 for better width, but without sacrificing imaging by moving mains too far apart. It's not Iosono 348.8, but hey!

http://www.audyssey.com/technology/dsx.html

 

[lsiberian]

I wouldn't do it. As PENG has pointed out, even if your power supply is being less taxed with your kind of setup, the amplifiers themselves can be too limited anyhow to take advantage of the power supply's remaining capability.

It seems that you're going to go nuts thinking about this. So... I say just get a pair of switchable bipole/dipoles, and then try both. I'm saying this, because I also went nuts thinking about it forever, and finally did it. Just get it over with! But, I also say this with the caveat that you are totally fine with everything else in your system. Room treatments possible?

The Axioms are kinda neat in that they are quadpolar. The high end PSBs are neat in that not only can they be set to dipole or bipole, but there are two sets of binding posts to allow, um, dual monopoles.

Lastly, since you really seem to love your surround, Audyssey just put this up on their site a couple of days ago. DSX 9.1 for better width, but without sacrificing imaging by moving mains too far apart. It's not Iosono 348.8, but hey!

http://www.audyssey.com/technology/dsx.html

Drool.

 

[jostenmeat]

Drool.

heehee. did you check out Iosono? IIRC, FilmMixer was saying they've got it at the Chinese Mann in LA, and that the rain forest demo doesn't just sound like rain is falling everywhere, it actually sounds like itis hitting your shoulders. 348.8!

 

[just-some-guy]

I wouldn't do it. As PENG has pointed out, even if your power supply is being less taxed with your kind of setup, the amplifiers themselves can be too limited anyhow to take advantage of the power supply's remaining capability.
.....................................................................
It seems that you're going to go nuts thinking about this. So... I say just get a pair of switchable bipole/dipoles, and then try both. I'm saying this, because I also went nuts thinking about it forever, and finally did it. Just get it over with! But, I also say this with the caveat that you are totally fine with everything else in your system. Room treatments possible?
............................................................................
The Axioms are kinda neat in that they are quadpolar. The high end PSBs are neat in that not only can they be set to dipole or bipole, but there are two sets of binding posts to allow, um, dual monopoles.
..............................................................................
Lastly, since you really seem to love your surround, Audyssey just put this up on their site a couple of days ago. DSX 9.1 for better width, but without sacrificing imaging by moving mains too far apart. It's not Iosono 348.8, but hey!

http://www.audyssey.com/technology/dsx.html

yeah, could be.
..........................
nah. i just want to get it right the first time.... and i'm not buying them. i am building them. i can't just "get over it" a $500 mistake.
.... ..........................
room treatments are in the works. but i would like to get those towers out of there. and permanently mount the rears. ... dual monopoles ? i thought thats what bipoles were
i have to find out what quadpolares are.
.......................................
yeah. i just love me stuff. you should see my HOT ROD. i love cranking uo a good movie !
i have to check out that 9.1 stuff. wth is iosono 348.8 ?