Center and Sub Issues

[Ares]

Hey Gang it's been awhile since I have posted anything on this side, spent a lot of time on the gaming forum side. I have 2 issues here and need some advice on how to address them. I have tried everything I could think of from crossover setting, placement and so forth but to no avail.

1) The sub has localization issues that I can't seem to get rid of.

2) When I'm watching movies or just TV viewing you can tell that the dialogue is coming from the center instead of giving the illusion that it's coming from the screen which is kind of distracting.

before this question gets asked I have tried to do proper placement of the speakers as the room would allow, the center is slightly below and 6" in front of the TV which is really the only place I could put it at the moment. The Sub is in front left side of the room with 3" clearance from the front wall and 5.5" off the side wall, I have everything set to small, crossover 80Hz for all.

So any help that you guys can provide will be most appreciated Thank You.

 

[Knucklehead90]

Low frequency localization usually kicks in around 120hz - some people can localize a sub at 100hz. Making sure your crossover points are set lower than 100hz should help.

As for the center channel - I find setting mine over the display and as close to the top of it as I can and pointing it right at me helps a lot. I've had mine below the display and decided I didn't like hearing dialog from 'down under' - no pun intended to our Aussie friends.

 

[Alex2507]

Those Mopad things might help your center out. They pretty much help all speakers out ... always hearing positive reports about them. Having that sub jammed into a corner like that is going to get a lot of that corner loading going on. They say to get it about a quarter of the way down the wall (5 inches ... puh-lease ) and a Gramma might help. Once again, only good reports from all owners. Seems like some people are just able to locate subs better than others too. Maybe congratulations are in order.

 

[njedpx3]

Knuklehead is right you can avoid subwoofer isolation by lowering the crossover point. At 80 hz you won't hear any isolation.

On center remember it is important to have timbre match with the fronts for seamless sound. The easy fix is just to lower the gain on the center. A better fix is to rerun you audessy or sound balancing. And the best fix (assuming you center doesn't match) is to get a matching center.

Peace and Good Sound,

Forest Man

 

[Ares]

Knucklehead90: Low frequency localization usually kicks in around 120hz - some people can localize a sub at 100hz. Making sure your crossover points are set lower than 100hz should help.

Hello Knucklehead, I have the crossover set @ 80Hz but I am still able to pick out the sub, at first I thought it was just all in my head but I had my cousin come over an had him place the sub in the room and run Audyssey and told him to cross everything @ 80Hz while I has out of the house, when I got back to the house I told him to blindfold me so I could not see where the sub was and I was still able to pick it out.

Alex2507: Those Mopad things might help your center out. They pretty much help all speakers out ... always hearing positive reports about them. Having that sub jammed into a corner like that is going to get a lot of that corner loading going on. They say to get it about a quarter of the way down the wall (5 inches ... puh-lease ) and a Gramma might help. Once again, only good reports from all owners. Seems like some people are just able to locate subs better than others too. Maybe congratulations are in order.

Hello Alex,I have the sub isolated from the floor and your recommendation is to move the sub a foot or more from the corner correct? What if I move the sub behind the listening position? because I have more room back there to move the sub around.

njedpx3: Knuklehead is right you can avoid subwoofer isolation by lowering the crossover point. At 80 hz you won't hear any isolation.

On center remember it is important to have timbre match with the fronts for seamless sound. The easy fix is just to lower the gain on the center. A better fix is to rerun you audessy or sound balancing. And the best fix (assuming you center doesn't match) is to get a matching center.

Peace and Good Sound,

Forest Man

Hello Bill, the setup I am trying to get right is the one in my Sig I ran Audyssey a few times and I always get the same results this is what the crossovers where before.

Fronts: 40Hz (large)

Center: 40Hz (small)

Rears : 40Hz (small)

Now I know that's not right especially for the center or the rears.

 

[sholling]

I'd start looking at moving and isolating (SubDude/Gramma) that subwoofer. Sitting in the corner like that you're going to hear some frequencies reinforced. It doesn't need to be at the front of the room. Heck in one room I have the sub behind me and in another I have the on sub sitting on a SubDude on top of gunsafe because it was the only place I had in that room that worked. Isolation made a big difference for all three of my subs.

Once that's done then after looking at PSB's specs I'd reset the all speakers to small, the crossover for the fronts to 50 or possibly 60hz, the center to 60hz, and the bookshelves to 70hz.

 

[Ares]

I have built a sub isolation platform which helped a lot at least now I don't hear it when I'm downstairs in the kitchen like before. Okay the crossover setting in the 1910 goes as follows:
40Hz, 60Hz, 80Hz, 90Hz, 100Hz, 110Hz, 120Hz, 150Hz, 200Hz and 250Hz

The fronts and the center @60Hz no problem, but for the rears since I can't do 70Hz should it stay at 80Hz or should I do 60Hz as well?

 

[skers_54]

I think your problem with the center might be because it's closer to you. When I first got my center channel, I played around with it about a foot or so in front of the TV and the soundstage was just off. The center was very prominent and sounded separated from L and R. What is the distance from the listening position to L, C and R?

 

[Ares]

Hello Skers, Do mean the actual physical distance or what Audyssey set the distance? Since I am not sure here I'll give you both #'s.

Physical Distance:

Left Front: 6'6"
Center: 7'4"
Right Front: 6'6"

Audyssey Distance:

Left Front: 5.9ft
Center: 5.6ft
Right Front: 5.9ft

 

[jostenmeat]

The fronts and the center @60Hz no problem, but for the rears since I can't do 70Hz should it stay at 80Hz or should I do 60Hz as well?

I'd do 80. I saw this thread earlier, but forgot to respond when I was last on. Better late than never.

You know, of the many things that I get confused about with AV, corner loading is definitely one of them, as it seems those who know what they are talking about normally recommend this. However, I have never, ever heard a corner loaded sub that wasn't very localizable. I am under the impression that lowering xover to 80 (or even lower) is not enough, because I think that the maximally excited modes at all of those boundaries are themselves localizable. Heck, my sub is on the sidewall, and every once in a while is it subtly localizable.

One expert whose writings I've read, Ethan Winer, says corner loading in all of its glory can be achieved after the necessary treating of the room.

Then you can get one of the main benefits, if not the biggest benefit, and that is efficiency from maximum room gain = sub/amp working less hard = less distorion = finally sounds better to your ears. Yet the treated space means you don't have those modal issues. Have cake, eat it.

However, I think you were saying you have a very modest room. In such case, I'm not sure that you need maximum efficiency. If possible, look towards beefy treatments in the future.

For now, place the sub AT the listening position, crawl around, and try placing the sub where it sounds best.

For the center, try to angle it sufficiently. On the tip of speakerman39 did I finally get around to using door stops to better angle my center. I wanted quite a healthy angle, so I opted for very large door stops like these:
http://www.amazon.com/gp/product/B00006IATN/ref=wms_ohs_product

My initial concern is if you have enough clearance from the display, and if you don't, if it is easily remedied.

Ciao, late to a show!

 

[sholling]

I have built a sub isolation platform which helped a lot at least now I don't hear it when I'm downstairs in the kitchen like before. Okay the crossover setting in the 1910 goes as follows:
40Hz, 60Hz, 80Hz, 90Hz, 100Hz, 110Hz, 120Hz, 150Hz, 200Hz and 250Hz

The fronts and the center @60Hz no problem, but for the rears since I can't do 70Hz should it stay at 80Hz or should I do 60Hz as well?

What I saw looking at your settings (fronts as large) was double bass, and from the specs it looks like a potential gap between the speakers and the subwoofer. Let's make it simple for now and set all of the crossovers for 80hz and all speakers to small. Later you can go back and play with the crossover points. When that's done then balance the output levels with a cheap Radio shack SPL meter. Note that rat shack SPL meters read deep bass roughly 6db low so compensate for that when balancing the output levels.

If that hasn't solved the problem then the next step is experimenting with subwoofer placement. With a little experimentation you should be able to narrow down a better location.

 

[Ares]

I do have the center angled 2" should I angle it more than this? because if I have to I have plenty of room to do so when I said the center is 6" in front of the TV what I should have said is the back of the center is 6" away of the TV. So I could put the center almost straight up with the tweeter and woofers pointing towards the ceiling. Yep the room is modest in size, I remember somebody called it a glorified closet. Would beefy room treatments be necessary? Since no two measurements are a like in this room 14'1" L bump out in the middle of the room reduces width to 6'1" the bump out is 4'7" in width then after that the back of the room is 7'2" with 9' ceiling.

 

[Ares]

What I saw looking at your settings (fronts as large) was double bass, and from the specs it looks like a potential gap between the speakers and the subwoofer. Let's make it simple for now and set all of the crossovers for 80hz and all speakers to small. Later you can go back and play with the crossover points. When that's done then balance the output levels with a cheap Radio shack SPL meter. Note that rat shack SPL meters read deep bass roughly 6db low so compensate for that when balancing the output levels.

If that hasn't solved the problem then the next step is experimenting with subwoofer placement. With a little experimentation you should be able to narrow down a better location.

I have the crossover set at 80Hz for all speakers and all the speakers are set to small currently, balanced the speaker levels with a SPL meter. So I guess the only thing left to do is experiment with placement.

 

[Alex2507]

I have everything set to small, crossover 80Hz for all.

I have the crossover set at 80Hz.

Set the crossover to 80Hz ...

Jostenmeat's crawling for bass suggestion is often recommended. Having the sub behind you is not a problem if you ask me but I have heard talk about there being a problem integrating the sub to the mains if they are more than half the wavelength of maybe the crossover frequency apart which would mean that you don't want them more than I think 7 feet apart. I'm trying to be vague about this because I'm repeating stuff I heard but didn't understand completely and am failing to do even that accurately but maybe you get the idea. However having them behind you is better than having a localizable frequency reinforced in the corner. Even though you have a crossover set to 80Hz the slope probably being 12db/octave still allows for localizable frequencies to potentially be reinforced. If you have a rear firing port I would say have it double the port diameter off the back wall and if your back wall is say 12' wide then have it placed 3' off the side.

Should you want to experiment with having the sub far away from the rec'r you can use a long coax with F connectors (something you might have kicking around) and RCA adapters. My room is weird. No matter where I put the sub I can tell where it is and I can hear sound coming from the front left of the room. It use to make me crazy but I stopped obsessing about it. Maybe the Grammas and a couple of wall treatments have reduced that. Now that I think about it the condition has been reduced and I have EQ'ed the mains as well but I'm just done messing with it so I don't care anymore.

Point the center's tweeter at the ear height of the listener ... not straight up. Those Mopad things will do that and more. I have some isolation things that I have built but for some reason I don't trust them as much as the Grammas even though they sound deader with a knuckle wrap test.

Jostenmeat is totally the guy to ask about that Audessy (sp) thing as he has taken vows or something to make people see that it is the best thing ever. Sorry for the long post but I really needed to do something useless to start off my day.

 

[Ares]

Hello Alex, the whole I can point the center straight up was to let him know I have enough space to work with in terms of angling the center. I thought I mentioned that the speakers are crossed @80Hz more than twice, oops I did it again I have a 20ft sub cable around here some where, the 6i's two ports are on the front so no worries there, having the HT gear up front makes it really difficult to move the sub around, where as the back of the room has a lot more floor space to work with.

 

[Alex2507]

I knew you wouldn't point the center straight up.

The AH store sells the MoPADs for as little as anyone else (last time it came up) and has free shipping. It's confusing shopping for them because they get described differently but they only come one way.

Don't be afraid of barrel connectors either to extend your RCA cable.

 

[skers_54]

Hello Skers, Do mean the actual physical distance or what Audyssey set the distance? Since I am not sure here I'll give you both #'s.

Physical Distance:

Left Front: 6'6"
Center: 7'4"
Right Front: 6'6"

Audyssey Distance:

Left Front: 5.9ft
Center: 5.6ft
Right Front: 5.9ft

That's weird. Both numbers should be the same (at least in my experience, outside of the sub). Try bumping the center distance up a foot or so. Also try setting the distances as close to what you measured as possible (Remember to measure from your ears to the tweeter). If either of those changes sound better, I'd re-run Audyssey until it gives you more correct distances.

 

[jostenmeat]

I do have the center angled 2" should I angle it more than this?

Well, it depends on how high the speaker is, how high your ears are. IOW, is it angled enough to be on-axis? If a bit below, get it straight to your head, or even barely above just for the experimentation.

because if I have to I have plenty of room to do so when I said the center is 6" in front of the TV what I should have said is the back of the center is 6" away of the TV.

A pic might not be a bad idea here. How low is the speaker? The lower it is, the more likely it is exciting midbass from the floor, which may have the center be more "localizable", away from the display.

So I could put the center almost straight up with the tweeter and woofers pointing towards the ceiling.

Good, now go experiment, since you have more than enough leeway. EDIT: come to think of it, with THAT much leeway, why wouldn't you further raise the height of the center speaker? I vote to raise it as much as you can, given the angling is enough to be on-axis. If it's raised as high as can be, it obviously will not have enough leeway to be angled. Find that magic height/angle.

Yep the room is modest in size, I remember somebody called it a glorified closet. Would beefy room treatments be necessary? Since no two measurements are a like in this room 14'1" L bump out in the middle of the room reduces width to 6'1" the bump out is 4'7" in width then after that the back of the room is 7'2" with 9' ceiling.

I don't understand the layout by description, but just know that the smaller the room is, the more imperative is bass trapping. If you hung out in the acoustics subforum here, you would know that some people would kill for larger rooms, so that the intensity of modal issues can be avoided.

However, some people have had very good luck with smaller rooms. I've only experienced nightmares. Even after a few hundred lbs of treatments.

 

[Ares]

I have been doing some experimenting with the sub moved it behind the listening position placement is 1'6" off the side wall and 2'7" off the back wall and raised 2' of the floor after doing that I ran Audyssey again and this is what I got.

Speaker Config

Fronts: Large- changed to Small
Center: Small
Rears: Small

Distance

Front L: 5.9ft
Front R: 5.8ft
Center: 6.5ft
Sub: 5.8ft
Rear L: 4.9
Rear R: 5.2

Channel Level

Front L: -6.0dB
Center: -5.0dB
Front R: -7.5dB
Rear R: -7.5dB
Rear L: -8.0dB
Sub: +3.0

Crossover

Fronts: -Full Band- changed to 80Hz
Center: 60Hz changed to 80Hz
Rears: 60Hz changed to 80Hz

Now I have noticed that localization is not as pronounced as before, but the center is still an issue.

jostenmeat: Good, now go experiment, since you have more than enough leeway. EDIT: come to think of it, with THAT much leeway, why wouldn't you further raise the height of the center speaker? I vote to raise it as much as you can, given the angling is enough to be on-axis. If it's raised as high as can be, it obviously will not have enough leeway to be angled. Find that magic height/angle.

This how the front is set up I have a pillar which the TV sits on, in front of pillar there is the TV stand which house's everything else, the pillar is 33" tall and the stand is 24" tall I have the center as close as possible to the TV and I did raise the center another 4" so the center sits 28" off the floor not including the 2" angle. The tweeter on the center is pointing right at my head I think I will try aiming it a little higher and see how that works.

 

[Ares]

Hey Gang, This was an ordeal to get everything right, first things first I decided to basically rip the room apart and started from scratch. I bought a larger area rug then I proceeded to move the LP (Listening Position) up 1ft after that it was time to focus on the sub, I download some test tones 20Hz-100Hz had to make sure they were Wav files, copied them to the PS3 HDD. Now it was time to figure out sub placement from everything I have read they always make it sound easy, but it's not as simple as they make it out to be at least in the guides so I consider them just that guides nothing more. I also downloaded Real Traps ModeCalc to help in the process along with some math, so now placement of the sub is 3'.5¼" off the back wall , 1'.8" off the side wall and 2'.2½" off the floor this was done for a crossover @80Hz. I went ahead and played the Wav files the 80Hz file was off so before I continued I went and ran Audyssey one more time and of course all the settings changed:

Distance:

Fronts 5.0
Center 5.0
Surr L 5.7
Surr R 6.1
Sub 6.7

Channel Level:

Front L -7.0
Center - 6.5
Front R - 6.5
Surr R - 6.5
Surr L - 6.5
Sub + 3.5

Well after all those changes I did I am happy to report I no longer have a localization issue with the sub and the center has disappeared. What I have I learned from all this location, location, location for the sub and experiment with placement of everything that is not nailed down Thanks Guys for all your help an ideals.