sound pannels

i have a question about sound pannels or acoustic pannels whatever there called?
if you put them behind your speakers what do they exactly do
do they make them sound better ? any advice would help thanx

That depends, what are the panels made of?

idk but im thinking of making a pair myself or buying a pair but i just want to know what they do first before doing so and i think there usually made of some kind of foam

If you're thinking of making acoustic panels the first place they should go is the first reflection points on the side walls.

What they do is damp reflections.

so like on the wall beside the speakers
because both of my speakers are angled in like 45 degrees maybe
but its not much but wouldnt i put the acoustic pannels behind the speakers ?
well i dont know much about them thats why im asking and what do they do exactly ?

If you walk around your room while clapping your hands you will hear echo's and a short reverb. Acoustic panels soak up sound and prevent those echo's when placed properly. Also, no echo means no reverb from the room.

To find the first reflection points; sit in your chair and have someone move a mirror along a side wall at at ear/eye height. When you can see the speaker closest to that wall in the mirror you have found your first reflection point. Appl the same process to both walls. To test this hang a large beach towel at speaker height at those two places. I'm sure you will hear the difference. The floor and ceiling also have first reflection points.

ahh i kinda get it now so u can hear less sounds from the room on the outside kinda ?
and ok i get it and if i make it myself what should i used im thinking of using some mdf for the back and get some wood like something that looks nice and make a border around it and put some foam or something in the middle something like that ?

Owens Corning fiberglass panels, cover them with grill cloth. Add wood trim if you like.

now where would i find or buy something like that ?
and dont forget i live in canada :P

Ummmm...your speakers have a toe in of 45 degrees? I wouldn't worry about the side walls so much. Start with the wall behind the speakers and then try the side walls. Do your speakers have rear firing ports? Either way, you just have to play around with them and see what result you get.

And no, it's not for how it sound outside of the room. That would be a different bag. You are placing them for how the room you are listening in will sound, while you are in it.

You should also be aware of the two main objectives with what you are doing. Absorbtion or dispertion. Basically, depending on where and what you use, you can absorb sounds to diminish them or disperse sounds to reflect or encourage them. Depends on the room...

yeah maybe 45 i think its probably less but i was gonna try and do the wall behind the speakers first and yeah my speakers have rear ports and i was looking on this one site http://www.soundaway.com/Acoustic_Co...05_p/17805.htm and its not expensive to make your own acoustic pannels i dont need huge pannels because my speakers are bookshelf but there really big bookshelf there acoustic research ar 226 ps they are about 20 inches tall and are on 24 inch speaker stands so i would just need to have a pannel about as big as the speaker or a little bigger right ?

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Originally Posted by ryanianmckinnon

yeah maybe 45 i think its probably less but i was gonna try and do the wall behind the speakers first and yeah my speakers have rear ports and i was looking on this one site http://www.soundaway.com/Acoustic_Co...05_p/17805.htm and its not expensive to make your own acoustic pannels i dont need huge pannels because my speakers are bookshelf but there really big bookshelf there acoustic research ar 226 ps they are about 20 inches tall and are on 24 inch speaker stands so i would just need to have a pannel about as big as the speaker or a little bigger right ?

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I can't say for sure. What I would say is make it with more than just your current speakers in mind. If you upgrade next year, it would be a shame to have to rebuild your panels because you made them too small.

Play around with the rear position. The ports are there to help the sound, you don't want to diminish it with a poorly placed panel.

This link has more info than you could possibly want to read....
http://www.ecoustics.com/Home/Access...ment_Articles/

Some people liked to have LEDE rooms. Live end and dead end. The speakers would be placed in the acousitcally treated end, dead end, so you hear more sound from the speakers and less reflections. You would sit in the live end and the delayed reflections is what you would hear from the speakers after the sound left the dead end.

One time I had a shelf for my speakers that was a little inset into the wall and I found a cheap idea for the early reflections. I used foam mattress pads that were convoluted. We also called them egg crate mattress pads because the hills and valleys looked like an egg carton. Easy to cut and position or cover large areas. Not pretty but they worked and when you find the areas you need them you can invest in better down the road.

yeah thats what i was thinking of doing is just using foam mattresses and cutting them like 12 x 24 and maybe make like a pannel to glue them to like some mdf with a border around it and glue the foam in the middle to make it at least look nice and still function good until i decide to upgrade

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Originally Posted by ryanianmckinnon

yeah thats what i was thinking of doing is just using foam mattresses and cutting them like 12 x 24 and maybe make like a pannel to glue them to like some mdf with a border around it and glue the foam in the middle to make it at least look nice and still function good until i decide to upgrade

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Here is a link to what I was thinking.

http://www.overstock.com/Home-Garden...2/product.html

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Originally Posted by ryanianmckinnon

yeah thats what i was thinking of doing is just using foam mattresses and cutting them like 12 x 24 and maybe make like a pannel to glue them to like some mdf with a border around it and glue the foam in the middle to make it at least look nice and still function good until i decide to upgrade

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Use Black Krylon spray paint and no one will know, they may even look good.

yeah john that's pretty much excatly what i was thinking and just make a nice looking frame for it so it looks like it was bought instead of made yourself and yeah put some kind of paint on it so it looks good

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Originally Posted by ryanianmckinnon

yeah john that's pretty much excatly what i was thinking and just make a nice looking frame for it so it looks like it was bought instead of made yourself and yeah put some kind of paint on it so it looks good

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there are acoustical paints that will not diminish their ability to absorb frequencies

you never said if you have a dedicated room. If so you can try adding rugs to the walls. It was a big improvement over what I had at first. Click on the pictures to get a close up.http://img22.imageshack.us/img22/9585/pict0012bz.th.jpg
http://img42.imageshack.us/img42/8803/pict0013t.th.jpg
http://img21.imageshack.us/img21/4167/pict0011el.th.jpg
http://img8.imageshack.us/img8/7711/pict0010w.th.jpg
http://img21.imageshack.us/img21/593/pict0009kt.th.jpg
http://img8.imageshack.us/img8/8053/pict0008ek.th.jpg

yeah i will deffinetly look for that kind of paint now and its not a seperate room actually its my bedroom which is ok in size but i wish it was bigger

Before adding any acoustic treatment, make sure you understand speaker placement See speaker manufacturers data sheet or visit one or more of the many sites that discuss this.

Example link to the Cardas Audio site (he has never done me wrong with his advice)
http://www.cardas.com/content.php?ar...ing=Room+Setup

the one problem about that is that i cant find anything about my speaker Ive been to many sites but i cant seem to find anything and to my knowledge the speakers were discontinued to which doesn't help

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Originally Posted by ryanianmckinnon

the one problem about that is that i cant find anything about my speaker Ive been to many sites but i cant seem to find anything and to my knowledge the speakers were discontinued to which doesn't help

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Speakers are usually monopoles (sound comes out the front). There are di-poles and bi-poles requiring special treatment, but most discussions are about standard speakers and you won't go far wrong in using that advice as at least as a stating point.

Bass wavelengths are so long compared to cabinet size it doesn't matter very much if the woofers are front or side mounted.

ok thanx that helps

I'm guessing here. Are your speakers positioned in the corners? If so, be aware unless they were designed for corner placement (Klipschorns) corners are the worst place to put them.

there not right in the corner there almost there like ten inches away from the corner

While I respect anyone wanting to do DIY bass traps and acoustical abosobers, it is not as easy as slapping some fabric or paint over fiberglass or foam. You really have to understand how much energy is being absorb in both the amplitude and frequency domain. You can very easily create a panel that has too much absorption which will suck the life out of the music.

Professional manufactured panels have their co-efficients measured meticulously so the user has a clear understanding of how they will act in their hometheaters. Without measuring instruments, you are flying blind, and can waste time and resources producing unacceptable results.

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Originally Posted by ryanianmckinnon

there not right in the corner there almost there like ten inches away from the corner

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The position that you have chosen for your speakers is about the worst you could possibly choose. There are many sites on the web that give you guide lines for proper speaker placement. The three links below were randomly selected after doing a Google search on "speaker positioning".

http://www.nsmaudio.com/brochures/basicstsetup.html
http://www.polkaudio.com/education/article.php?id=15
http://www.onhifi.com/features/20000815.htm

ok i understand the DIY but the one thing i kinda have a problem with is the stereo is only in my bedroom and i know its not the greatest room but its all i got the room is 9x12 i think

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Originally Posted by Sir Terrence the Terrible

While I respect anyone wanting to do DIY bass traps and acoustical abosobers, it is not as easy as slapping some fabric or paint over fiberglass or foam. You really have to understand how much energy is being absorb in both the amplitude and frequency domain. You can very easily create a panel that has too much absorption which will suck the life out of the music.

Professional manufactured panels have their co-efficients measured meticulously so the user has a clear understanding of how they will act in their hometheaters. Without measuring instruments, you are flying blind, and can waste time and resources producing unacceptable results.

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True, true Terrence. I just make sure it doesn't cost too much for starters. Secondly, I find a way of doing things easily so that labour isn't too taxing. With these things in mind, it can be fun trying different things out. Certainly a different dimension of audio that most don't bother to even think about.

I have my own special gauge, it starts at "not bad" and actually has "whoa, wicked" on it

I made these today at work. I found a roll of 100% polyester partitioning fabric. Quite dense but thin. I've covered some particle board with the fabric. Obviously it's late and I can't trial it right now. We'll see...

I certainly can't afford the professionally made panels or traps, so this is it for me. Better than nothing.

I was using Cardas' Golden Cuboid but it kept getting modified for one reason or another. Mostly my 3 year old son. I just don't have the dedicated space to fully commit to Cardas' formula.S

Stapled and spray glued. I also included some light railing for mounting to the wall.

I changed plans with the bass traps. I put some paneling into the corners instead. I've covered the traps with a foil like material and now, I'm just moving them around, playing.

Corners...

Full view

Listening Seat

that looks not bad yeah u gotta plan out how much labour its gonna cost you and the materials and compare that to purchasing them online and see what one is cheaper and just mostly look around and see what your options are but if i did decide to make my own i have all the tools i need or at least access to them to build them

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Originally Posted by poppachubby

Listening Seat

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Looks good pappaC....But the proof is in the listening. Did it do what you wanted it to do? Do you have the panels up to high?

frenchmon

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Originally Posted by Sir Terrence the Terrible

You can very easily create a panel that has too much absorption which will suck the life out of the music...Professional manufactured panels have their co-efficients measured meticulously so the user has a clear understanding of how they will act in their hometheaters.

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That is certainly true. One can always over damp a room, but using commercially made treatments doesn't solve the problem either. The use of any treatments always requires experimentation since each room is a unique combination of naturally reflective and absorptive properties and numerous other factors like shape and wall type. I found that what worked in my previous dedicated room was not what worked best in my current one. While my previous room was highly reflective, the current one is less so. Indeed, I found that the absorptive panels used in the old room removed some of the natural ambience of the new room. The paneling and asymmetrical walls in the current room rendered them unnecessary. I redeployed them to the garage which suffered massive slap echo and sorely needed them.

As for bass traps, you would be hard pressed to use too many in any environment. I use a dozen and could really use more.

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Originally Posted by Sir Terrence the Terrible

Without measuring instruments, you are flying blind, and can waste time and resources producing unacceptable results.

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True again, but I aver that most folks can make demonstrable improvements with a small budget using only their ears. One does not have to have a thorough room analysis before proceeding to correct obvious issues. Having said that, I did use basic instrumentation and measurements to help assist with speaker and bass trap placement for the most neutral response.

rw

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Originally Posted by poppachubby

I changed plans with the bass traps. I put some paneling into the corners instead. I've covered the traps with a foil like material and now, I'm just moving them around, playing.

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Hmmm. If they are open at the top as they appear to be, they really do not serve as traps. The DIY flavor I use mimics the ASC bass trap design which is sealed. Take a look here. Hollow tubes are just not the same. Note that only half their circumference is reflective. While along the wall placement is used in the best installations, one typically begins with corner placement for the most effect.

rw

as well as visual beauty, i imagine the open framework damps some of the reflected sounds in a random manner.

;^)