Question about Paradigm ADP surround speakers labeled left and right.

[MPWONG]

I recently installed a pair of Paradigm ADP-150 speakers for a 5.1 HT setup. I also noticed that I accidently reversed the speaker labeled "left" with the speaker labeled "right" in the installation.

Does anyone know why Paradigm labels the speakers this way? Will it sound different at all if reversed? Are the bi-polar designs not symmetrically constructed?

Thanks ahead of time.

MPW

[cam]

I recently installed a pair of Paradigm ADP-150 speakers for a 5.1 HT setup. I also noticed that I accidently reversed the speaker labeled "left" with the speaker labeled "right" in the installation.

Does anyone know why Paradigm labels the speakers this way? Will it sound different at all if reversed? Are the bi-polar designs not symmetrically constructed?

Thanks ahead of time.

MPW

These speakers are not bi-poles, they are di-poles. If you install them correct you will have the forward facing speaker in phase and the rearward speaker out of phase. Since you reversed them you now have the forward facing speakers out of phase. When installed on the walls at your sides they must not get mixed up. If you place them on the back wall (not recomended) you can reverse your speakers and apparently receive a phantom center sound. I have never tried it. For di-poles to work the way they are supposed to, they must be set up properly.

[kexodusc]

Hmmm, could you do a quick fix by reversing the speaker wire polarities at the receiver?

[VRDUB]

These speakers are not bi-poles, they are di-poles. If you install them correct you will have the forward facing speaker in phase and the rearward speaker out of phase. Since you reversed them you now have the forward facing speakers out of phase. When installed on the walls at your sides they must not get mixed up. If you place them on the back wall (not recomended) you can reverse your speakers and apparently receive a phantom center sound. I have never tried it. For di-poles to work the way they are supposed to, they must be set up properly.

Why do you say that placing the dipoles on the rear wall is not recomended?
Do you mean for a 5.1 setup only, or not on the back wall at all? I ask this 'cause I have a 7.1 set up with two sets of dipoles (sides and back wall) and to me it sounds great

[kexodusc]

Good point, in my limited experiments with 7.1 and dipoles/bipoles I much preffered the dipoles in the rear than on the sides. I preferred direct radiating speakers all around, but there was a really wide rear sound field created with the dipoles in the back.
I don't see why they couldn't go there. In the end it's all personal preference anyway.

If you search the threads, there were a few other people the came to the same conclusion several months ago...

[VRDUB]

Can't seem to find that thread, sounds like an interesting read.

[VRDUB]

I recently installed a pair of Paradigm ADP-150 speakers for a 5.1 HT setup. I also noticed that I accidently reversed the speaker labeled "left" with the speaker labeled "right" in the installation.

Does anyone know why Paradigm labels the speakers this way? Will it sound different at all if reversed? Are the bi-polar designs not symmetrically constructed?

Thanks ahead of time.

MPW

Why can't you just switch them around? If they are anything like the ADP 370's they should just slide out.

[kexodusc]

I can't find the thread either...I have a feeling it was a side-topic of another subject...I gave up after about 10 minutes...
Sorry.

[cam]

Why do you say that placing the dipoles on the rear wall is not recomended?
Do you mean for a 5.1 setup only, or not on the back wall at all? I ask this 'cause I have a 7.1 set up with two sets of dipoles (sides and back wall) and to me it sounds great

Yes I mean for a 5.1 set up. If you use di-poles behind you in 5.1 you just can't get your ears in the null whereas on the direct sides you can. For 7.1 I think the two center rears could be di-poles whether the side surrounds are di-poles, bi-poles, or direct firing.

[Luis31]

Guys,

I sent an e-mail to Paradigm's tech support a while back asking whether the ADP are true" bipoles or dipoles and they responded "ADP" stands for "adaptive pole" and they were designed to have the "directionality" of a bipole and the "diffuse" sound characteristics of a dipole speaker in 1 box. On the ADP's, the tweeters are wired out of phase, while the woofers are wired in phase. As to placement, they suggested either on the sides or in the back for 5.1 and/or 7.1 systems.

Hope this helps...

-Luis31

[VRDUB]

I can't find the thread either...I have a feeling it was a side-topic of another subject...I gave up after about 10 minutes...
Sorry.

That's ok, I only searched for about 5 minutes thanks for the extra effort.

As for Luis31's post: When I ran the auto set-up on the Denon 2805 I thought that it would give me an in phase or out of phase reading when I got my ADP's hooked up. Could that be because the 2805 does not check "phase" or for what Paradigm describes in Luis' e-mail?

[Sir Terrence the Terrible]

Why do you say that placing the dipoles on the rear wall is not recomended?
Do you mean for a 5.1 setup only, or not on the back wall at all? I ask this 'cause I have a 7.1 set up with two sets of dipoles (sides and back wall) and to me it sounds great

Dipoles can be placed in the rear, but they work against our hearing machanism in that position.

Because we have these two flaps on our outer ear(pinna), any sounds coming from behind are going to be reflected off of them. These reflections delay, and change the frequency response of the signal going into the inner ear. The delay will diffuse the sound, and the reflections cause high frequency loss. The high frequencies are how we ascertain direction, so the loss of highs slightly confuses the direction of the sound(think of jet airplanes overhead). So you have diffusion, and ear confusion when you place dipoles in the rear. That is why THX recommends direct radiators for the rear center channel, it eleminates both of these problems, and work with the decorrolating circuits to electrically diffuse, rather than acoustically do it. You have more control that way.

Placing them to the sides creates side wall reflections that have a more direct path to the ears, in spite of the fact you are sitting in the null. Usually the null is not deep enough to eliminate all sound, but to reduce it in amplitude enough, and delay it enough to allow the front speaker arrival to hit the ears first.

If you watch more movies than listen to music, dipoles all around is cool. But if DVD-A and SACD are in your hometheater menu, then dipoles all around are going to create some problems, as instruments can sometimes be placed in the surround channels, and the frequency mismatches between a more directional front, and a diffused rear will change the tonal quality of those instruments when directed to the rear.

Now, if you understood all of that, explain it to me!

[Sir Terrence the Terrible]

Hmmm, could you do a quick fix by reversing the speaker wire polarities at the receiver?

Can't do that with this kind of speaker, or the woofer will be out of phase with the front speakers. The whole speakers in the case must have their position swapped, or you will have phase issues between the fronts and rears.

[kexodusc]

You lost me in that one Sir T. Maybe if you could dumb it down to my calibre and try again...

Because we have these two flaps on our outer ear(pinna), any sounds coming from behind are going to be reflected off of them. These reflections delay, and change the frequency response of the signal going into the inner ear. The delay will diffuse the sound, and the reflections cause high frequency loss. The high frequencies are how we ascertain direction, so the loss of highs slightly confuses the direction of the sound(think of jet airplanes overhead).

I'm not sure why this physical attribute of our ears would somehow come into play for dipoles situated behind, and cause unwanted effects, but not matter for direct radiators situated behind?
Truth is when I tried it out in my own home, all it did was make the whole rear wall of my room sound alive when the speakers were fed a signal. In fact, the rear sound field was as wide as the front. It wasn't really bad, just not my cup of tea because of mulit-channel audio. It was diffuse, but there was no mistaking the sound was coming from the rear, it just sounded "bigger" and "deeper" than the sides or front by comparison.

Could this be a case of the theory not agreeing with the real world results, or are the effects of these ear flaps really negligible? I could accept that, I have no problem identifying sound from behind me. Any thoughts?

[VRDUB]

Yeah I can see your point with M/C music that is recorded with a certain sound dedicated to a certain speaker. But if you are sitting in the sweet spot and a drum roll goes across the rear I'm sure it will be smoother with dipole then with direct rad. speakers. This could all be rubbish 'cause I know nothing about M/C music and if they would ever put a drum roll across the rear, but I think that some sounds are meant to be heard from the rear (ie. bullets hitting a back wall) I think this makes some sense.

[kexodusc]

This could all be rubbish 'cause I know nothing about M/C music and if they would ever put a drum roll across the rear, but I think that some sounds are meant to be heard from the rear (ie. bullets hitting a back wall) I think this makes some sense.

Generally, I find dipoles are great for big sounds, like a car approaching from the back, a jet swooping over you, or gunfire...but a tightly focused, precision impact from a drum-roll, moving across the rear doesn't sound right IMO. Could all be personal preference in the end though. I don't think rear imaging is best served by bipolar/dipolar speakers in multi-channel audio, though.

[VRDUB]

If M/C music is anything like 5/7ch. stereo, I must admit that I'm not a big fan as I enjoy music in two channel only. Mind you this may all change the minute I actually sit down a have a good listen to M/C audio, but like I said if it's anything like 5/7ch. stereo I'm sure I would switch it to hi res 2ch.
I just hope it doesn't sound like 5/7ch. stereo.

[Sir Terrence the Terrible]

You lost me in that one Sir T. Maybe if you could dumb it down to my calibre and try again...

Sorry, sometimes I get just a little carried away..

I'm not sure why this physical attribute of our ears would somehow come into play for dipoles situated behind, and cause unwanted effects, but not matter for direct radiators situated behind?

Direct radiators project 90-95% of their energy forward, with residual(what's left)signals that are reflected off the speaker baffle, and walls. Dipoles have about a 50/50 direct to reflection ratio, with a majority of the highs(which assist our ears in determining direction) flowing away from our ears. The flaps of our ears(pinna) reflects sound coming from the rearward locations, and delays its travel to our inner ear canal. Both of these processes changes the frequency response to the ears(roll off of the highs mostly). When you consider this fact combined with a speaker that sends its highs away from the ears, you have a pretty deep roll off of the high frequencies when the sound is coming from behind your head. Monopoles send more energy towards the ears, therefore more high frequencies stand a chance of reaching the inner ear directly, and even the strength of the reflections on the pinna are more profound when the speaker is not aiming most of its signals away from the ears.

Dipoles= More reflections away from the ears, less highs reaching the inner ear.
Monopoles= More direct signals to the ear, with strong reflections with more highs to the ears.

Truth is when I tried it out in my own home, all it did was make the whole rear wall of my room sound alive when the speakers were fed a signal.

Yes, but when the signal is mixed using point source or monopole speakers, it will not sound the same as a dipole speaker reproducing the same signal. It will sound more diffuse and less localized. If the intention of the engineer was to create a tight phantom image between surrounds, it would not be possible with dipoles. Some Dts CD's have voices in all of the channels, they would sound noticeable different because your front speakers are direct radiators, and the rear surrounds have phase mismatches built in which will alter the tonal qualities of the voice.

In fact, the rear sound field was as wide as the front. It wasn't really bad, just not my cup of tea because of mulit-channel audio. It was diffuse, but there was no mistaking the sound was coming from the rear, it just sounded "bigger" and "deeper" than the sides or front by comparison.

Yes, and it will sound like that on all sources, all of the time, even when it is not warranted. It is not adjustable, or adaptable, and that's the problem

Could this be a case of the theory not agreeing with the real world results, or are the effects of these ear flaps really negligible? I could accept that, I have no problem identifying sound from behind me. Any thoughts?

No, actually its more like we can adapt to anything. When you see the dummy head measurements of dipoles placed in different positions around the sides and rear of the head, you notice a pretty dramatic roll off in the upper frequencies, but all of the reflections allow us to ignore that, until it is compared with something more direct. The dipoles spaciousness does come at the price of image specificity.

[Sir Terrence the Terrible]

Generally, I find dipoles are great for big sounds, like a car approaching from the back, a jet swooping over you, or gunfire...but a tightly focused, precision impact from a drum-roll, moving across the rear doesn't sound right IMO. Could all be personal preference in the end though. I don't think rear imaging is best served by bipolar/dipolar speakers in multi-channel audio, though.

Oh, on the contrary bipolars in the surround hemisphere are quite effective, and really reduce the "stereo in the head" phenomena we hear with direct radiators. They are truly the best of both worlds. They have no phase issues(so they can be pinpoint), yet the reflections the design imparts doesn't reduce image specificity like they do with dipoles.

[kexodusc]

Thanks, Terrence...so in a home theater only setup (assuming no multi-channel audio) you'd rank surround speakers in the following order:
1) Bipolars
2) Direct Radiators
3) Dipolars

And prefer the Direct Radiators in the rear?
You mentioned phantom images...the biggest hate on I had with bipolars was the weird effect they had to me when panning from rear to side to front...To me the transitions were terrible. The ambient effects were far better than direct radiators, but localized sounds, as you claimed were too diffuse.

Another question, if I may. As room size increases (mine is 20 X 24) and distance from the speaker increases, does the effect of the dipolar/bipolar sound diffusion become less substantial? That is do direct radiators improve in performance the further they're placed away from the viewing position?
I ask because I'm in the process of replacing all my speakers with DIY jobbies, and perhaps I'll rethink the dipole/bipole options...I can always build 2 more main speakers for multi-channel audio anyway.

Thanks again.

[Sir Terrence the Terrible]

Thanks, Terrence...so in a home theater only setup (assuming no multi-channel audio) you'd rank surround speakers in the following order:
1) Bipolars
2) Direct Radiators
3) Dipolars

If I had my choice, and no multichannel music was involved, I would choose 6-8 direct radiators, or 4 bipolars. I did a installation no too long ago where I used 9 direct radiators for the surrounds. 3 on each side wall, 3 on the back wall. VERY good sound, good localization, excellent diffusion when called for, and great dynamics.

And prefer the Direct Radiators in the rear?

Absolutely for the reasons I outlined earlier.

You mentioned phantom images...the biggest hate on I had with bipolars was the weird effect they had to me when panning from rear to side to front...To me the transitions were terrible. The ambient effects were far better than direct radiators, but localized sounds, as you claimed were too diffuse.

I currently use bipolars for my L/R surround speakers. I do not have this problem at all. I have a test disk I use to judge channel consistancy from speaker to speaker. It consists of filtered pink noise, that is panned from channel to channel in a complete circle around the room. Not only can you clearly follow this pink noise ball around the room in my setup, but it tracks perfectly between speakers with little to no tonal change whatsoever. The mid/upper bass driver of my front speakers, and the woofer in the surrounds are indentical, and the tweeters on the front and rear speakers are the same. I think driver matching on all speakers is pretty important if you want good clean panning

Another question, if I may. As room size increases (mine is 20 X 24) and distance from the speaker increases, does the effect of the dipolar/bipolar sound diffusion become less substantial? That is do direct radiators improve in performance the further they're placed away from the viewing position?

No, the diffusive effect actually increases because you are now adding in room reflections created by the speakers themselves. The closer you sit to the speakers, the more influence of the speaker. The farther you sit away from the speaker, the more the rooms influence dictates what you hear. This goes for all design types. For larger rooms I recommend mulitple direct radiators, because that is the sound that both dipoles, and bipoles are designed to emmulate in smaller rooms

I ask because I'm in the process of replacing all my speakers with DIY jobbies, and perhaps I'll rethink the dipole/bipole options...

I would seriously consider the multiple direct radiator route, especially if you have a pretty large room

I can always build 2 more main speakers for multi-channel audio anyway.
Thanks again.

Such talent........the best I can do is type over 100 wpm, and shower and sing at the same time! Some guys have all the luck...