Absorb or reflect behind ML

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Caspyr

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In a dedicated theater I have SL3's up front. Because of the "stage" they are only about 2.5 feet from the wall behind them.

I am remodeling the theater, and am wondering if, based on that, I should have a reflective surface behind them or an absorptive surface.

She wants to put up Velvet Screen Curtains, but when open they will bunch up right behind the L and R speakers.
 

Tube60

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Caspyr said:
In a dedicated theater I have SL3's up front. Because of the "stage" they are only about 2.5 feet from the wall behind them.

I am remodeling the theater, and am wondering if, based on that, I should have a reflective surface behind them or an absorptive surface.

She wants to put up Velvet Screen Curtains, but when open they will bunch up right behind the L and R speakers.
Definitely have an absorbent surface behind your panels. The reflections coming off the wall behind them can often muddy the imaging. There are threads on this forum that cover the different techniques that have proven useful.
 

twich54

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Tube60 said:
Definitely have an absorbent surface behind your panels. The reflections coming off the wall behind them can often muddy the imaging. There are threads on this forum that cover the different techniques that have proven useful.

Also depending on distances from corners, traps might be in order as well.
 

kach22i

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I like diffusion behind my speakers, which is reflected sound, just broken up a bit and scattered.

In my situation (also close to the wall) absorptive material in-between the speakers, not behind the speakers is best.

I have read of others having the same opinion, but I did experiment before being convinced.
 

MOON

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You defiately need to diffuse the rear wave, not absorb it. I use a tweak I read about under fine tunes in Mar 2002 Stereophile. Buy a slatted bi-fold door. Prime it with spray paint primer and paint it the same color as your walls. Put the slatted door behind your logans with the hinghed part at the center of the door in line with the middle of the stator panel and have each side of the door slanting back on a 30%angle . Each side slanting back touching the wall.

This cheap tweak works wonders. Once you try it you will be amazed. You can cut the door down from the 6 ft 6 inch height to fit smaller logans. I have to get new doors, full size as I just upgraded from Aireus i's to Oddessey's which are a full foot 2 inches higher requiring the taller full size door.

Also if you can get the SL 3's out more from the wall behind them that would be 100% better. Had my Airieus 50 inces off , the Oddesseys are 52 inches out.

Cheers
 

theWB

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Tube60 said:
Definitely have an absorbent surface behind your panels. The reflections coming off the wall behind them can often muddy the imaging. There are threads on this forum that cover the different techniques that have proven useful.
I'm in agreement with Ross,I really liked the improvment in clarity after putting absorbtion behind the panels,and as Dave said after putting bass traps in the corner it really brought out,deepened, and cleaned up the bass.The difference with the bass traps was dramatic.I used Panels and Traps from GIK Acoustics,very inexpensive and effective.
http://www.gikacoustics.com/
 

DTB300

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theWB said:
I used Panels and Traps from GIK Acoustics,very inexpensive and effective. http://www.gikacoustics.com/
Same here with absorption behind my main speakers.

For bass trapping, the GIK is a great product for the cost. I am using the 244 panels now, and plan to order a couple of more shortly. Glenn is also a great guy to deal with, discussing your situation and getting a great recommendation on how to proceed.

Dan
 

theWB

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DTB300 said:
Same here with absorption behind my main speakers.

For bass trapping, the GIK is a great product for the cost. I am using the 244 panels now, and plan to order a couple of more shortly. Glenn is also a great guy to deal with, discussing your situation and getting a great recommendation on how to proceed.

Dan
Dan,I have the 244's behind my mains and use the new tri-traps in the front corners.The cleanup of the bass was dramatic with the tri-traps.And I also found Glenn great to deal with.Delivery was quick.
 

benleeys

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Caspyr said:
In a dedicated theater I have SL3's up front......
She wants to put up Velvet Screen Curtains, but when open they will bunch up right behind the L and R speakers.
Caspyr,
I can tell you from personal experience that velvet curtains are the last thing you would want behind your SL3's. Spent $500 on these recently and had to take them off immediately. For a start, your vocals will sound like the singer has got a stuffy nose!
But if you really must have a screen curtain, best is use the thinnest material other than velvet you can find.
Ben
 
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Reverb

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kach22i said:
I like diffusion behind my speakers, which is reflected sound, just broken up a bit and scattered.

In my situation (also close to the wall) absorptive material in-between the speakers, not behind the speakers is best.

I have read of others having the same opinion, but I did experiment before being convinced.
My preference is to defuse the back wave and absorb the sidewalls.
 

SugarMedia

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MOON said:
I use a tweak I read about under fine tunes in Mar 2002 Stereophile.
Moon, do you have a picture of your tweak?
 

DTB300

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MOON said:
You defiately need to diffuse the rear wave, not absorb it.
I tried diffusion in my room and found the sound stage moved too far forward for my liking. This is why I choose absorption.

The "shutter type" door you describe is an interesting concept for diffusion. I wonder if they come if different types of wood for different types of sound???? The only issue I see with this tweak is normally diffusion is done with many different points or protrusions for proper diffusion - like the Skyline diffusors, etc. But it is a nice cheap tweak to see if it performs and solves the problems you are having.

As everyone reading this thread can see, there is no right or wrong way here for a setup. Each person needs to try both and see which we like better.

Dan
 

SugarMedia

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Dan, I'm guessing he is talking about this type of shutter, yeah? If so, I like the idea of being able to direct the bottom and top in different directions.

Just unsure how I can make it look good and barely obvious in my room.
 

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DTB300

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SugarMedia said:
Dan, I'm guessing he is talking about this type of shutter, yeah? If so, I like the idea of being able to direct the bottom and top in different directions. Just unsure how I can make it look good and barely obvious in my room.
That is the same thing I was visualizing. And with the moving slats, I would guess you could change the sound somewhat.

The trouble with room treatments is that they will stick out as not being part of the room - except those picture type absorbers. But with the ability to cover them with some GOM, you can make them look fairly nice.

Dan
 

twich54

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DTB300 said:
The trouble with room treatments is that they will stick out as not being part of the room - except those picture type absorbers. But with the ability to cover them with some GOM, you can make them look fairly nice.

Dan

So true Dan, unless your lucky enough to have plenty of room and can take advantage of plants (excellent diffusers) , which do look quite natural.
 

MOON

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Hi Sugarmedia,

The picture you have of the slatted doors are the ones I use. I do have pictures of the ones behind my Aeirus i's but I will post a new picture soon as I just aquired a set of Oddessey's and will have the full size 6 ft 6 inch door behind the Oddessey's.

I cut the door down in height that was behind the Aeirus. I am off tommorrow to buy the spray primmer and 2 new doors and then paint them again to match the wall paint.. Actually I go to a green home recycling center , you can get the doors for $20 each. Ouite a bargain considering what they do for the sound. Hopefully within a week I shall show the pictures.

After you paint the doors the same color as the room they blend right in, even my wife likes then, high Waf when primmed and painted. The spray can primmer really cuts down on the prep time.

Cheers, Greg
 
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Bimotarich

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A little greenery can really save you some green

I use large potted plants behind my SL3s and it works pretty well. My speakers are fairly close to the rear walls (30inches) but the plants seem to do a good job of diffusing the sound and they look nice as well! I have curtains for side wall absorbtion which also seem to help. I am thinking of experimenting with some kind of horn system behind the woofer portion of the speaker to help with bass response. Anyone tried this approach?
 

SugarMedia

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Well, my wife already said, "No way." And I sort of agree with her in that it aesthetically won't create a balanced feel for our listening room. Too bad because I like the idea of these shutters and would be curious to try them.

A few months back I posted a few photos of this guy who took absorbing panels and then framed them with crown molding. That did look very nice. But again, for my room, I feel screwed on this pyramid shape of the way my cabinet is, to the plasma, to the speakers.

:(
 

MOON

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Sugarmedia,

I took my smaller panels that were behind the Aerius i's out before I got the Oddessey's so I would be able to do measureing tape measurments when the new speakers arrived. My wife said it looked bare without the slatted doors and that it added quite a lot to the look of the room. Once these doors are painted to match the walls they blend right in.

The reason they work so well is that half the rear wave is redirected to the center of the room and the other half to the side wall. This clears up the midrange big time and you will have a more focused soundstage.

If you are running Logans with nothing behind the rear wave bounces off the wall and right back to the source- the stator mucking up the sound considerably, probably without you even realizing it.

Having absorbtion behind Logans really defeats the purpose of having a rear wave in the first place.
 

DTB300

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MOON said:
Having absorbtion behind Logans really defeats the purpose of having a rear wave in the first place.
I would agree with your statement if the wall behind the speakers was completly covered with absorption sucking up every bit of the rear wave. I do not think any of us here using absorbtion, have ever stated that.

Having "some" absorption or "some" diffusion is what people need to try out. We are not trying to "completely" absorb, or "completely" diffuse the sound.

Dan
 
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