A Guide to Bipolar, Dipolar, & Direct-Radiating Monopole Surround Speakers (PART I)

[Big Daddy]

Originally Posted by Blu-Benny

hoping someone can dumb down the bi-polar & di-polar info for me.

please forgive my ignorance....last time i was up to speed on HT was when optical & digital coax were the new big thing and 6.1 DTS was the shizz!!!

so is the bi/di-polar just the way the speakers are wired to the recv'r or amp??

it's not the actual speaker itself is it??

what i'm concerned about @ this point is i'm looking to order speaker wire this week so i can wire my HT.

i need to know of anything important when doing the wiring b/c it's gonna be in wall and i really don't want to have to rip it out and start over once the drywall is up.

As Jomari said, dipole/bipole refers to the way the internal wirings are done and has nothing to do with the way you connect the speakers to the receiver. Bipole/dipole speakers typically have identical drivers on two sides. In the case of bipole (in-phase) speakers, both drivers go out and in at the same time. In the case of dipole (out-of-phase) speakers, when one driver goes out, the other driver goes in.

Bipole



Dipole

[Blu-Benny]

Originally Posted by jomari

in a nutshell, bipolars and dipolars consist of two drivers or more, both pointing in two different directions. The main difference is that Bipoles are in phase, and Dipoles are out of phase. Yes, its the actual speaker itself, but with Dipolars you have to wire it accordingly.

What kind of speaker are you using for inwalls then? For what its worth, there arent that many Dipolars or Bipolar in wall speakers. They need to interact to the room.

You can find an abundance of resources on the first posting on this thread, care of Big Daddys time and effort.

i'm gonna run the speaker wire in wall, i think i've decided on jbl speakers.

floors for the front and possibly 4 identical 3 or 4 way bookshelves and then the 2 subs & center of course.

i've been reading this thread (i actually printed everything off ) and was just getting confused on everything....like i said, his is all new to me.

thanks jomari and big daddy.

as long as i know i can run a single wire to each speaker location and be good to go, i feel better.

[Big Daddy]

Originally Posted by Blu-Benny

i'm gonna run the speaker wire in wall, i think i've decided on jbl speakers.

floors for the front and possibly 4 identical 3 or 4 way bookshelves and then the 2 subs & center of course.

i've been reading this thread (i actually printed everything off ) and was just getting confused on everything....like i said, his is all new to me.

thanks jomari and big daddy.

as long as i know i can run a single wire to each speaker location and be good to go, i feel better.

It is a good idea to install the surround speakers a couple of feet above your head when you are sitting down to watch a movie.

[jomari]

Originally Posted by Blu-Benny

i'm gonna run the speaker wire in wall, i think i've decided on jbl speakers.

floors for the front and possibly 4 identical 3 or 4 way bookshelves and then the 2 subs & center of course.

i've been reading this thread (i actually printed everything off ) and was just getting confused on everything....like i said, his is all new to me.

thanks jomari and big daddy.

as long as i know i can run a single wire to each speaker location and be good to go, i feel better.

got the model numbers by chance? anyhoo, if you plan to, let us know via pm and/or start a new thread if you'd like. you've been around right?

with regards to BD's tip, dont forget
- measure twice, cut once. try to find means to see how good it would sound initially prior to cutting. not a bad idea to use a smaller speaker (satellites for example) and initially place them on the desired position, and work from there.

- speaker wire should be rated appropriately. You'd want to check your fire code firsthand, and be certain that it follows the said prerequisites. Why? safety first. acoustics second.

- lastly, check on the insulation of the wall, see how good the walls are in regards to keeping the noise/sound isolated in that room, and doesnt 'leak' into the adjoining room or the rooms above.

printing these documents are a good thing. you officially have new 'bathroom material'.

as always, feel free to ask more questions when the time comes.

[HAMP]

I know depending on a room and placement of speakers will make a difference in the AQ. Things can be done such as speaker stands, wall mounts and the possible hung from the ceiling.

This post is about surround speakers and I have four Monitor Audio RXFX and I have them in Di-pole mode. I love this mode so much, that I have not givin the bi-pole option a chance and I doubt if I ever do.

I have my back rear hanging from the ceiling and right now that is my only option for now.

I just want to mention, that the AQ between mounted on a wall and just hanging is like night & day or 'F.M. stereo' compared to 'A.M. talk show'.

If it was just about the ambient sound, which surrounds are about, the rear AQ would have been fine. When comparing the two different ambient sounds, I really feel it makes a bigger difference then most say or I have read.

I'm not sure if I feel this way, because of Timbre matching and I have stated myself in the past that it does not make a difference with surrounds or does it make a difference in reality. My side are Timbre matched, but with them hanging, I can't say they match, even tho they are the same speakers.

It just shows how a wall or placement can make a difference in what I have experienced.

Maybe all of this is just to say, I don’t like the hanging option for placement for speakers.

If Big Daddy is reading this, but I did re-make the video you commented on in the ‘Home Theater Video Tread’

[Triggerhappy]

Hi, new to the forum and have been reading with interest. I notice that there hasn't been a post from BD in a while so I hope that BD is still monitoring this post.

I was hoping that I can get some advice on my current set up..

I picked up a Yamaha RX-V667 which then snowballed into picking up used, CSiA4, FXi3 and a PSW505 (all for $425), these are led by a pair of RTi70s as fronts. Current set-up is 5.1.

I have a question as to how and where to place the FXi3s and whether it is worth getting a pair of RTi3s as an additional suround channel to make 7.1.

First my room:
- basement home theater in a large 35x20 enclosure.
- The theater is set in the right corner of the room which results in the left side of the theater area being open to a relatively empty space (used by the little ones to play hockey and what not - Canadian eh!).
- The theater area is roughly 20 by 14 with the listening position set about 10 feet from the centre and front channels. Because of the lack of room, the couch is pushed out maybe 2 feet from the wall.

Current FXi3 placement:
- set as bi-pole, I have the FXi3s set on speaker stands (temporary) at a little higher than ear level. These are aligned so that they are just inside of the fronts roughly 4 feet away from the listening position. I have them placed so that the woofers are facing the listener.

Option1:

Leave them where they are, but mount them on the wall roughly 3 feet above the listening position.

Challenge(A) - The couch and listening position may be too close to the FXi3s.

Challenge(B): because the left side of the theater is open, the bi-pole effect may not be fully realized.

Question: in this set-up should the woofers face the listening position or away (currently facing the listening position)?

Option2:

Move the FXi3 to the side of the listening position. These would need to be mounted high near the ceiling. (While the left side of the theater) is open, there is a bulk head that would allow this). The speakers would be set to dipole with the woofers facing away from the listening position.

Challenge(A): Given that the left side is open, the di-pole effect on the left FXi3 maybe minimized.


Question about going to 7.1 surround.

Question 1: is it worth it with my current set-up
Question 2: If I get a pair of RtiA3s where should the FXi3s be placed. As dipoles on the side or as bipoles at the rear..

I know that this is a lot of questions.. but I am really very confused on what to do. I think i know what the best solution is: orientate the room differently so that the fronts and center is shooting down the length..but that will be a lot of work given I just mounted my projector and screen not to mention all the wiring. (for now lets say that is not an option!)

Advice, insights, directions would be much appreciated!

[Big Daddy]

Originally Posted by Triggerhappy

Hi, new to the forum and have been reading with interest. I notice that there hasn't been a post from BD in a while so I hope that BD is still monitoring this post.

I was hoping that I can get some advice on my current set up..

I picked up a Yamaha RX-V667 which then snowballed into picking up used, CSiA4, FXi3 and a PSW505 (all for $425), these are led by a pair of RTi70s as fronts. Current set-up is 5.1.

I have a question as to how and where to place the FXi3s and whether it is worth getting a pair of RTi3s as an additional suround channel to make 7.1.

First my room:
- basement home theater in a large 35x20 enclosure.
- The theater is set in the right corner of the room which results in the left side of the theater area being open to a relatively empty space (used by the little ones to play hockey and what not - Canadian eh!).
- The theater area is roughly 20 by 14 with the listening position set about 10 feet from the centre and front channels. Because of the lack of room, the couch is pushed out maybe 2 feet from the wall.

Current FXi3 placement:
- set as bi-pole, I have the FXi3s set on speaker stands (temporary) at a little higher than ear level. These are aligned so that they are just inside of the fronts roughly 4 feet away from the listening position. I have them placed so that the woofers are facing the listener.

Option1:

Leave them where they are, but mount them on the wall roughly 3 feet above the listening position.

Challenge(A) - The couch and listening position may be too close to the FXi3s.

Challenge(B): because the left side of the theater is open, the bi-pole effect may not be fully realized.

Question: in this set-up should the woofers face the listening position or away (currently facing the listening position)?

Option2:

Move the FXi3 to the side of the listening position. These would need to be mounted high near the ceiling. (While the left side of the theater) is open, there is a bulk head that would allow this). The speakers would be set to dipole with the woofers facing away from the listening position.

Challenge(A): Given that the left side is open, the di-pole effect on the left FXi3 maybe minimized.


Question about going to 7.1 surround.

Question 1: is it worth it with my current set-up
Question 2: If I get a pair of RtiA3s where should the FXi3s be placed. As dipoles on the side or as bipoles at the rear..

I know that this is a lot of questions.. but I am really very confused on what to do. I think i know what the best solution is: orientate the room differently so that the fronts and center is shooting down the length..but that will be a lot of work given I just mounted my projector and screen not to mention all the wiring. (for now lets say that is not an option!)

Advice, insights, directions would be much appreciated!

It is hard to visualize your room without actually being there. These are my suggestions:

1. Put your main listening couch in a place in the room that is not against the wall. Make sure the seat is at least a few feet away from the back wall.
2. Your main front speakers should be about 6 to 10 ft apart. Do not put them too close to the front wall. Make sure they are about a foot and a half to 2 feet away from the front wall.
3. As far as your surround speakers are concerned, setting them to bipole will give you more flexibility. In order to receive maximum benefit from dipole surround speakers, you need to be able to sit exactly in the middle of their null spot. That is not always possible.
4. Attach your bipole side surround speakers to the wall, celing, or put them on a stand so that they are a couple of feet above and behind your head when you are sitting down.
5. It is true that Bipole speakers send sound waves in different directions and they reflect against the wall for a more diffuse sound. However, we all have to make compromises. I use two bipole side surrounds on the right side against the wall. The two bipole left surround speakers are in the open area and I have attached them to the ceiling with brackets. The height of all 4 side surround speakers are the same. The speakers against the wall will have a little more bass and play louder. That is why I had to turn the level of the two speakers on the left a couple of dB's higher. Your auto calibration program inside the receiver wil take care of that. Furthermore, since I use an 89Hz crossover for the surround speakers, their bass response should not play a big factor.
6. As far as two additional surround speakers for the back are concerned, it really depends on you. The vast majority of the movies are in 5.1 format. In order to use the two rear surround speakers, you need to use Dolby PLIIx to matrix the information from the side surround speakers to the two rear speakers. The effect can fun and enjoyable. It all depends on your room size and the position of the main seat. If you have enough space between the main listening area and the back wall and you are not sitting too close to the TV, go ahead and install two additional back surround speakers. If you don't have the space behind you and you are alr4eady sitting too close to the TV, don't bother.

[Triggerhappy]

[QUOTE]

Originally Posted by Big Daddy

It is hard to visualize your room without actually being there.

Thanks BD, I think you have confirmed my thoughts on how to set up. I have attached some pictures:

Here is a wide shot of my basement room.
pic1a.jpg

The couch is as far as I can bring it into the room. As it is now, it is a little overwhelming with 16:9 movies! The fronts are about 9' apart. I know that the red couch is interfering with the right speaker, but its all I got for now.

pic2.JPG

I did set up the speakers last night as it was easy to get some dry wall plugs and mount them as bi-poles on the back wall. I figured I would need to get special mounts to mount them properly as dipoles as they would need to be high against the ceiling and they would need to be angled down (correct?).

As you can see the rear speakers aren't very far apart (6 feet). I didn't place them further apart because I didn't want to get the right-rear to close to that corner and I would also lose wall on the left side to diffuse the left rear. The amp set-up is already compensating by boosting the left bipolar by 4.5DBs. (PS don't mind the little satellite in the corner, its from my old system.)

Based on the pics. Do you think this is the right approach? Do you think mounting to the sides would be better? If so, as Bipoles or Dipoles?

Again, thanks for your advise! You are the Daddy of all things audio!

[Big Daddy]

Originally Posted by Triggerhappy

Based on the pics. Do you think this is the right approach? Do you think mounting to the sides would be better? If so, as Bipoles or Dipoles?

Again, thanks for your advise! You are the Daddy of all things audio!

It doesn't look bad at all. My suggestion is to move the right front speaker slightly away from the right wall. Toe in the front speakers very gently. Not too much. Also put your center speaker on a stand. Tilting it upward so that it points toward your head when you are sitting down is a good idea. The way your room is shaped, you are much better off using bipole surround as opposed to dipole.

Make sure you run the calibration program every time you move the speakers around.

[Triggerhappy]

Originally Posted by Big Daddy

It doesn't look bad at all. My suggestion is to move the right front speaker slightly away from the right wall. Toe in the front speakers very gently. Not too much. Also put your center speaker on a stand. Tilting it upward so that it points toward your head when you are sitting down is a good idea. The way your room is shaped, you are much better off using bipole surround as opposed to dipole.

Make sure you run the calibration program every time you move the speakers around.

Thanks! Yep calibration down every time adjustments are made.

Any thoughts on how and where to put some sound absorbing material? (eg. in between the bipoles? along the right wall?

I also read something about a bass trap, but am not sure how or where to set-up?

Thanks again!

[Big Daddy]

Originally Posted by Triggerhappy

Thanks! Yep calibration down every time adjustments are made.

Any thoughts on how and where to put some sound absorbing material? (eg. in between the bipoles? along the right wall?

I also read something about a bass trap, but am not sure how or where to set-up?

Thanks again!

You can put some treatment behind the front speakers, on the side walls, between the two rear speakers, and on the ceiling. You can put diffusers to the right and left of the rear speakers. Some bass traps against the corners of the room or where the ceiling and the side walls meet. Chances are that you will get kicked out by your wife after you install all the room treatments. Use the following diagrams as a guide:

Reflections.jpg


Absorption.jpg


Diffusion.jpg


Echo.jpg


Treatment.jpg

[Triggerhappy]

Originally Posted by Big Daddy

You can put diffusers to the right and left of the rear speakers.

Thanks again BD, and sorry for all the questions...but there always ssems to be more questions!

Wouldn't putting diffusers and/or absorbers inbetween and beside the bipolars defeat their purpose?

Chances are that you will get kicked out by your wife after you install all the room treatments. Use the following diagrams as a guide:

Luckily she hates it down there anyways!

Thanks again!

[Big Daddy]

Originally Posted by Triggerhappy

Thanks again BD, and sorry for all the questions...but there always ssems to be more questions!

Wouldn't putting diffusers and/or absorbers inbetween and beside the bipolars defeat their purpose?



Luckily she hates it down there anyways!

Thanks again!

You don't necessarily put the absorbers and diffusers there for the surround speakers. You put them there so that the sound from the front speakers (the most important sound) does not reflect back from the rear wall and muddy the sound. Here are some more pictures for you to get you kicked out of the house faster.

[Triggerhappy]

Originally Posted by Big Daddy

You don't necessarily put the absorbers and diffusers there for the surround speakers. You put them there so that the sound from the front speakers (the most important sound) does not reflect back from the rear wall and muddy the sound. Here are some more pictures for you to get you kicked out of the house faster.

Thanks again! I can only dream of a home theatre set-up like those at this moment..

[Triggerhappy]

Hey BD, I have been doing some research and potential, absorption panels. Would panels from ATS acoustics do the trick?

I was think a 2'x2' panel between the rears as well as maybe 2 to 3 2'x4' panels behind the fronts and center channel. I would then get some nice drapes to act as an absorber for the right wall.

Would this work for now?

I can think about bass traps and reflectors at a later date.

Thanks
JD

[icposse2000]

Quick question--I've got a room with lots of built in bookshelves along the right and back walls (as facing the TV). Can bipole or dipole speakers be placed within these built-in bookshelves, or will that completely cripple how they work through reflective sound? The left wall doesn't have the shelves, so that may cause uneven sound between the right and left walls if I place the speakers there. I can't mount the speakers on the beams of the bookshelves because of the dreaded WAF.

Would I be better off with direct radiating speakers or in-ceiling speakers (which are my last resort b/c the ceiling is actually very nice)? Any thoughts would be helpful!

[Fors*]

Originally Posted by icposse2000

Quick question--I've got a room with lots of built in bookshelves along the right and back walls (as facing the TV). Can bipole or dipole speakers be placed within these built-in bookshelves, or will that completely cripple how they work through reflective sound? The left wall doesn't have the shelves, so that may cause uneven sound between the right and left walls if I place the speakers there. I can't mount the speakers on the beams of the bookshelves because of the dreaded WAF.

Would I be better off with direct radiating speakers or in-ceiling speakers (which are my last resort b/c the ceiling is actually very nice)? Any thoughts would be helpful!

I think that room would not serve the bipoles/dipoles well at all. You will have lots of reflections from within the bookcases and out occurring withint the room. IMO, the rooms acoustics are not really suitable for bipoler speakers. Direct radiating seems to be your best best. Plus with the book shelves, it should help with offering many different placement options.

[icposse2000]

Great, thanks for the info Fors. That is what I have been leaning towards as well. I was thinking of placing them in the top back corners of the room (probably 5 feet above the listeners' heads), and aiming them slightly downwards so the sound still goes overhead but not by quite as much. I know you don't want to aim them directly at the listeners or you get the 'hey look at me' effect where the surround draws too much attention to itself.

Now I just have to find some speakers to pair with my paradigm millenia 20s. Unfortunately paradigm makes ADPs for almost all of their surrounds.

[Fors*]

Originally Posted by icposse2000

Great, thanks for the info Fors. That is what I have been leaning towards as well. I was thinking of placing them in the top back corners of the room (probably 5 feet above the listeners' heads), and aiming them slightly downwards so the sound still goes overhead but not by quite as much. I know you don't want to aim them directly at the listeners or you get the 'hey look at me' effect where the surround draws too much attention to itself.

Now I just have to find some speakers to pair with my paradigm millenia 20s. Unfortunately paradigm makes ADPs for almost all of their surrounds.

I have a set of older Titans and an Atom in my set-up. Not sure what would work for you with your Millenia's that isn't an ADP......

[icposse2000]

Yeah, had been looking at the atoms, the micro monitors, and the MilleniaOne2.0 satellites. Might be able to convince my wife to let me vertically mount another set of millenia 20s on the bookshelf beams, but something tells me that may not go over well

I guess it's off to the dealer again to do some listening. Thanks again for the advice Fors.