Dual centers

Posted by: brwsaw

Dual centers - 05/07/13 01:21 AM

Can adding a second identical center help if the first center falls short of the target?
I have considered the simplicity of adding the same center next to my current center. They would sit side by side and would probably be angled slightly, towards the lazy boy on each end of the love seat.
They don't have the best specs but together they would have 8-2.5" aluminum drivers.
And I could leave each component as is where is.
I'm eager to hear pro's, con's and horror stories.
Woofers: Quad 2-1/2" aluminum cone
Tweeter: 1-1/8" soft dome
Frequency Response: 90 Hz - 45 kHz
Nominal Input Power: 40W
Maximum Input Power: 120W
Sensitivity: 90 dB
Impedance: 6 ohms
Dimensions (WxHxD): 17-5/16" x 3-11/16" x 4-15/16"
Posted by: CatBrat

Re: Dual centers - 05/07/13 01:42 AM

Normally a dual center is placed one above and one below the TV. That's how I have them. Never heard anyone mention them side by side.
Posted by: Ken.C

Re: Dual centers - 05/07/13 08:10 AM

Michael D. in Alaska has them side by side. He uses vertical centers, though. Horizontal centers side by side would be... odd.
Posted by: brwsaw

Re: Dual centers - 05/07/13 10:05 AM

Dual M80's...
Posted by: casey01

Re: Dual centers - 05/07/13 11:10 AM

Originally Posted By: brwsaw
Can adding a second identical center help if the first center falls short of the target?
I have considered the simplicity of adding the same center next to my current center. They would sit side by side and would probably be angled slightly, towards the lazy boy on each end of the love seat.
They don't have the best specs but together they would have 8-2.5" aluminum drivers.
And I could leave each component as is where is.
I'm eager to hear pro's, con's and horror stories.
Woofers: Quad 2-1/2" aluminum cone
Tweeter: 1-1/8" soft dome
Frequency Response: 90 Hz - 45 kHz
Nominal Input Power: 40W
Maximum Input Power: 120W
Sensitivity: 90 dB
Impedance: 6 ohms
Dimensions (WxHxD): 17-5/16" x 3-11/16" x 4-15/16"


I would think not. The speaker sizes are comparable to those on soundbars where they have eight or ten of them and designed for a totally different application primarily in a one-speaker only with sub configuration. Whether its one center channel or five, it looks like the drivers on your particular model are just too small and the crossover would have to be set too high especially when you have M80s as mains making any sort of seamless transition of sound virtually impossible. As I always say, when it comes to speakers "you really can't defy the laws of physics".
Posted by: brwsaw

Re: Dual centers - 05/07/13 11:13 AM

Yeah, I already knew it was wishful thinking. It would have been an easy fix though.
Posted by: CatBrat

Re: Dual centers - 05/07/13 01:21 PM

How come nobody uses high quality headsets. You could just have a set of plugins for them nearby, and everyone could get immersive sound. Something I might try playing with in the future, just for fun.

If I can figure out how to do this without increasing hearing loss.
Posted by: michael_d

Re: Dual centers - 05/11/13 01:52 PM

Originally Posted By: Ken.C
Michael D. in Alaska has them side by side. He uses vertical centers, though. Horizontal centers side by side would be... odd.


I moved to the VP160 a while back. Way-mo-betta...
Posted by: brwsaw

Re: Dual centers - 05/11/13 08:28 PM

A new center is still my priority.
I'm hung up on trying to fit too many things in too small a space.
Posted by: brwsaw

Re: Dual centers - 05/26/13 05:33 PM

Lets pretend I want to use a pair of QS4's or QS8's for my center channel.
Would I benefit more from giving each its own channel of amplification or by running both of a single channel.
Its a two part question. Should I use the single output on the reciever or swap two channels off the amp?
Posted by: CatBrat

Re: Dual centers - 05/26/13 08:10 PM

I have dual mains and centers, and using a single channel for each. Wasn't even aware there was a way to reassign amps to different channels.
Posted by: brwsaw

Re: Dual centers - 05/27/13 12:33 AM

I won't be re assigning. Just removing rears from the amp and using the recievers built in amp.
I'd preffer to keep it simple while I test the theory.
The simplest would be to run them off the receivers single output with a paired cable.
The recievers only powering the center and presence now. Theres headroom available.
Would running 2 8ohm speakers mean a 4ohm load?
Posted by: Ken.C

Re: Dual centers - 05/27/13 09:16 AM

Yes, cabled to the same output, 2 8 ohm speakers would be 4 ohms.
Posted by: brwsaw

Re: Dual centers - 05/27/13 12:20 PM

Is there a benifit or detriment to using seperate outputs?
Posted by: Ken.C

Re: Dual centers - 05/27/13 12:25 PM

Almost no one (aside from CatBrat) does what you are proposing, which, if I understand it correctly, is running two pairs of L/R fronts. There is no second center output on any receiver I know of, so if you're talking about running dual centers, your question is moot.

Seriously, dude, you've got the worst case of upgraditis I've ever seen.
Posted by: brwsaw

Re: Dual centers - 05/27/13 12:35 PM

I would be using 2 channels from the amp if I did.
The reciever could handle the load though.
I like to swap speakers. Looking at the cost of the stand and new center it almost makes sense to add another pair of M80's. I will work my old towers back into L /R and will try the dual 80's for a while. It won't be for a while though.
I'd like to hear Brians setup too.
I like how my layout sounds but the center has to go. It will join the parts pile asap.
Posted by: Ken.C

Re: Dual centers - 05/27/13 12:42 PM

You won't be able to run a pair of M80s off of one channel; that would be a load of 2 ohms--and you can't reassign a rear amp to the center channel.
Posted by: CatBrat

Re: Dual centers - 05/27/13 01:19 PM

Kens right, I'd be leery of running 2 4ohm loads on the same channel. Doesn't mean I wouldn't try it, but I'd definitely keep a close watch on how much heat the amp / receiver generated.

So far running 2 8ohm loads hasn't presented a problem on 3 different mid to high end receivers.
Posted by: brwsaw

Re: Dual centers - 05/27/13 02:44 PM

I'd be running 2 QS4's or QS8's off one(receiver or amp). I'm not sure if having the empty channel on the amp would have any benifit except that at 4 ohm I should have more potential headroom.
M80's would be on seperate channels from the amp. Always will be.
Posted by: brwsaw

Re: Dual centers - 05/27/13 02:47 PM

Originally Posted By: Ken.C
Almost no one (aside from CatBrat) does what you are proposing, which, if I understand it correctly, is running two pairs of L/R fronts. There is no second center output on any receiver I know of, so if you're talking about running dual centers, your question is moot.

Seriously, dude, you've got the worst case of upgraditis I've ever seen.


It wouldn't be dual left and right.
Just two centers with the L/R move slighlty farther apart.
Posted by: brwsaw

Re: Dual centers - 05/27/13 09:41 PM



I like the idea.
I wonder if it will work.
I did scale a different stand than the one I'm currently using but I've seen it and know it would work if the center wasn't to be placed in it.
Posted by: JohnK

Re: Dual centers - 05/27/13 10:44 PM

Of course it'll "work", within the inherent limits of the arrangement. As compared to using the M80 mains to carry the center channel material in a "phantom center" setup, placing two M80s(or other speakers)directly alongside the screen for center channel speakers has several effects. The center channel volume can be increased independently of the mains since different speakers are carrying it. The center channel image would be exactly centered for someone directly in the middle between them. As the listener would move to the side, so would the center channel image move with him, but not farther out than the center speaker on that side.
Posted by: brwsaw

Re: Dual centers - 05/27/13 11:35 PM

So in theory this could provide 2 sweet spots on the love seat?
Could it also provide better imaging for seats below the QS's?
Posted by: JohnK

Re: Dual centers - 05/27/13 11:50 PM

Not really two "sweet spots". A single center channel speaker keeps the center material imaged directly in the middle of the screen, regardless of whether the listener is off to the side. Using two separated(sidewise)center speakers keeps the image in front of the listener who's off to the side, but it's no longer in the center of the screen where the voices etc., are generally supposed to be coming from, so that probably shouldn't be termed listening in the sweet spot.
Posted by: brwsaw

Re: Dual centers - 05/27/13 11:57 PM

I think I'll try it on my next 2 day weekend.
Might wait until my QS8's arrive and add my first banana plugs into the mix.
Posted by: brwsaw

Re: Dual centers - 05/28/13 12:36 AM

Nope.
Just ruled it out.
Won't even bother trying dual M80's.
Sat down to watch TV and two things happened.
I opened the cabinet door and hit my left tower. I forgot I had changed the toe-in on a whim last night.
Second, when I turned on the Simpsons (no longer broadcast in surround on Fox) Homer was planted in my right tower. My right tower is 4' from the center of the screen.
It won't work.
Now...dual QS4's are still on the auditioning block.
Posted by: brwsaw

Re: Dual centers - 05/31/13 12:49 AM

I hate to say it but the idea of using dual M80's for the center channel got to me.
I will take the doors off the cabinet just to try it out.
Only harm will be if I waste a couple hours swapping them back and forth.
Two day weekend coming up in 3 weeks.
Stay tuned.
Posted by: casey01

Re: Dual centers - 05/31/13 11:07 AM

Originally Posted By: brwsaw
I hate to say it but the idea of using dual M80's for the center channel got to me.
I will take the doors off the cabinet just to try it out.
Only harm will be if I waste a couple hours swapping them back and forth.
Two day weekend coming up in 3 weeks.
Stay tuned.


I think this is an arrangement that many of us(space and pocketbook notwithstanding) would love to have. If you have either one or in your case, two M80's as center channels along with L/R M80s, you will get that perfect timbre match in the front sound stage that is just not possible with any horizontal center. Also the vertical speakers will give you a truer wider angle of dispersion so toed-in in such a manner to hit all the angles it should sound just fine.
Posted by: MarkSJohnson

Re: Dual centers - 05/31/13 11:10 AM

Originally Posted By: casey01
you will get that perfect timbre match in the front sound stage


I don't disagree that identical speakers across the front are the ideal situation, but remember that even identical speakers can, and likely will, have a slight timbre different due to positioning within the room.
Posted by: brwsaw

Re: Dual centers - 05/31/13 09:00 PM

Timbre!!
Might have to call in sick on Monday.