How I built my bass traps...

[filthyrich]

Cojo, those look great!!

That is really close to the design I was going to go with. My question is how you plan to mount them to the wall if there is no mid braces going across to mount from.

Are you just going to use the actual 1" frame to mount from?

[Cojo]

Originally Posted by morpheuzrecords

Hi,

here are a cuple of lousy pictures of the traps I have build - this thread was a big source of information

I have made 7 pieces each si 1250x625x13 mm

guess I need to clean thoose windows , my place is a total mess now I just moved into the new controlroom and am rebuilding the live room and bulding a vocal booth/iso booth

Great! At least you have your own control room... My control room is my living room right now!

[Cojo]

Originally Posted by filthyrich

Cojo, those look great!!

That is really close to the design I was going to go with. My question is how you plan to mount them to the wall if there is no mid braces going across to mount from.

Are you just going to use the actual 1" frame to mount from?

That was my thought, but it would be no problem to change them and do as you say either.

For now they are free standing. I havn't decided if I want to make all the holes in the walls and ceiling yet. As you can see in the post above my control room is my living room for the moment! I'm still looking out for a decent place.

I can tell you that the last design really made a big different. If I could go back and redo the other I would.

[xmostynx]

Originally Posted by Cojo

I can tell you that the last design really made a big different. If I could go back and redo the other I would.

Cojo your suggesting the holes in the side as well? I'm saving cash, and planning on placement and sizes..

i'm gonna have to rent a jigsaw if you say the holes in the sides of the bass traps make them better!

i really dig the thread man...bigtime

PS..my control room is my bedroom!

[SkiBum]

I'm not a professional acoustician, but I have studied the subject enough to know there is some missing data in this long thread. I have a couple comments:

First, about the traps mentioned in the original thread, these are not bass traps. They are full range absorbers. If you use 6" of 703 you have a full range absorber, like an open window - all sound goes in and does not come out. To absorb bass only, you have to either use a membrane design or a Helmholz resonator.

You should be able to get bass absorbtion by putting them in your corners at 45degrees to the walls, where the bass builds up.

Another post said that you can leave plastic wrapped around the 703 and they work almost as well. Sorry, but that's illogical if you know how they work. The air pressure waves go into the material and are absorbed. If the waves can't get into the inside of the material they are not going to have any significant effect at all.

I would recommend studying more about the subject before building traps or you won't get the great results you are after for your hard work and money. Dalton Everest's books are excellent.

I made traps - 3 kinds: low mid and full range - based on his designs and with his calculations, and they worked beautifully in my old studio.

Also, hemp may have a sound absorbtion rating that is decent (although I doubt it), but I would want to actually know before I used it in my studio, although I applaud you for finding a healthier material than fiberglass (cotton batting works pretty well). I just hope it is really working for you. Considering how much you put up it might do OK on some frequencies. You can probably find an acoustic rating for it somewhere. Maybe the manufacturer can help with that.

I'm not trying to be a know it all or rain on anybody's parade. Acoustics is a fun subject. Understanding the science, it can be even more useful.

[Cojo]

Originally Posted by SkiBum

I'm not a professional acoustician, but I have studied the subject enough to know there is some missing data in this long thread. I have a couple comments:

Nor am I.

Originally Posted by SkiBum

First, about the traps mentioned in the original thread, these are not bass traps. They are full range absorbers. If you use 6" of 703 you have a full range absorber, like an open window - all sound goes in and does not come out. To absorb bass only, you have to either use a membrane design or a Helmholz resonator.

Yes I know... I've tried to change the title of the thread but I'm not aloud too.

Originally Posted by SkiBum

You should be able to get bass absorbtion by putting them in your corners at 45degrees to the walls, where the bass builds up.

All my traps are put in corners except the 2" cloud but that is for early reflections.

Originally Posted by SkiBum

Another post said that you can leave plastic wrapped around the 703 and they work almost as well. Sorry, but that's illogical if you know how they work. The air pressure waves go into the material and are absorbed. If the waves can't get into the inside of the material they are not going to have any significant effect at all..

As I said, I'm not an acoustic enginear but I think that low frequency goes through the plastic. Put a plastic bag around your head and tell me what you hear, if you hear anything?

Originally Posted by SkiBum

I would recommend studying more about the subject before building traps or you won't get the great results you are after for your hard work and money. Dalton Everest's books are excellent.

I've read ALOT but you can always read more. Thanks for the tip!

Originally Posted by SkiBum

I made traps - 3 kinds: low mid and full range - based on his designs and with his calculations, and they worked beautifully in my old studio.

Originally Posted by SkiBum

Also, hemp may have a sound absorbtion rating that is decent (although I doubt it), but I would want to actually know before I used it in my studio, although I applaud you for finding a healthier material than fiberglass (cotton batting works pretty well). I just hope it is really working for you. Considering how much you put up it might do OK on some frequencies. You can probably find an acoustic rating for it somewhere. Maybe the manufacturer can help with that.

I have not made any hemp traps. But it seems to work for other people.

Originally Posted by SkiBum

I'm not trying to be a know it all or rain on anybody's parade. Acoustics is a fun subject. Understanding the science, it can be even more useful.

I can't tell you how many times the dime has fallen down and the light gone up! You learn as long you live I suppose!

/Cojo

[Cojo]

Originally Posted by xmostynx

Cojo your suggesting the holes in the side as well? I'm saving cash, and planning on placement and sizes..

i'm gonna have to rent a jigsaw if you say the holes in the sides of the bass traps make them better!

i really dig the thread man...bigtime

PS..my control room is my bedroom!

The holes were timeconsuming to do but if the traps are as mine, 6" deep, you gain about one trap every second trap you make!

If they are 4" or lesser it may be harder to do. Actually if they are 4" you don't need a big frame to support them, just make a frame like on the back like on a canvas and staple the fabric around it.

[bpape]

Skibum.

Your logic on the plastic over the fiberglass doesn't fly - sorry. What you say is true for upper mids and highs in they they will mostly reflect off the plastic. The bass will go right through that thin plastic like it doesn't even exist.

Think about it, bass goes right through doors, windows, drywall, etc. A thin piece of plastic isn't going to do diddly to stop it.

Bryan

[matucha]

But then you cover the plastic with fabric and viola!, you've got your high freq. absorbtion back (or at least half back).

[SamNOISE]

I intend on doing the same thing as most of you fellows, but instead of using plain fabric, I have been collecting the large sacks that raw, unroasted coffee beans ship in - from the many coffee shops who roast in the area. These all have very cool designs on them and I thing it will make an otherwise boring box a little more interesting / aesthetically pleasing.

Andrew D.
www.cdnav.com

[macmod]

Originally Posted by SamNOISE

I intend on doing the same thing as most of you fellows, but instead of using plain fabric, I have been collecting the large sacks that raw, unroasted coffee beans ship in - from the many coffee shops who roast in the area. These all have very cool designs on them and I thing it will make an otherwise boring box a little more interesting / aesthetically pleasing.

Andrew D.
www.cdnav.com

Well Andrew, don't think the bags from our Amsterdam coffeshops are usefull for this

[ATTACH]http://i104.photobucket.com/albums/m164/reinhardroffel/zipbag.jpg[/ATTACH]
Just kidding, carry on,
Macmod

[Cojo]

Originally Posted by macmod

Well Andrew, don't think the bags from our Amsterdam coffeshops are usefull for this

[ATTACH]http://i104.photobucket.com/albums/m164/reinhardroffel/zipbag.jpg[/ATTACH]
Just kidding, carry on,
Macmod

...maby filled with hemp?

[djui5]

Originally Posted by SamNOISE

I intend on doing the same thing as most of you fellows, but instead of using plain fabric, I have been collecting the large sacks that raw, unroasted coffee beans ship in - from the many coffee shops who roast in the area. These all have very cool designs on them and I thing it will make an otherwise boring box a little more interesting / aesthetically pleasing.

Andrew D.
www.cdnav.com

Should smell good too :)

[Pier]

Hi everyone

I'm going to build 6 of these broadband absorbers for my homestudio 1.80m x 0,6m x 0,25m (6' x 2' x 1' aprox).

I was just thinking of leaving one wedge of 5cm (2 inches I think) of air between the insulation panels. Like 2 rockwhool + 1 air + 2rockwhool panels.

Do you think this air gap will make noticeable benefits for bass absorption or should I stick with the original design as its simpler and easier to build?

Regards

[Glenn Kuras]

Originally Posted by Pier

Hi everyone

I'm going to build 6 of these broadband absorbers for my homestudio 1.80m x 0,6m x 0,25m (6' x 2' x 1' aprox).

I was just thinking of leaving one wedge of 5cm (2 inches I think) of air between the insulation panels. Like 2 rockwhool + 1 air + 2rockwhool panels.

Do you think this air gap will make noticeable benefits for bass absorption or should I stick with the original design as its simpler and easier to build?

Regards

The air gap will help, but filling that 1" gap with rockwool would work even better. But with that said air is FREE so looking at cost per sabins the gap is better. Though you do have to ask yourself "Are you trying to have the best or save on some money?".

Glenn

[Pier]

Originally Posted by myfipie

The air gap will help, but filling that 1" gap with rockwool would work even better. But with that said air is FREE so looking at cost per sabins the gap is better. Though you do have to ask yourself "Are you trying to have the best or save on some money?".

Glenn

Yeah I supose it's only a matter of price really... :)

Today I've found a rockwhool dealer and will calculate the difference in cost.

BTW This forum is great

[xmostynx]

hey guys..

i got enough money saved to make about 9 traps..

3 going in corners, and 3 going on the wall behind my monitors..

really excited to purchase the materials, and then build!!! haha

i wanted to know..

the 703 is sturdy..yes..but as long as I secure the mineral wool good..it should hold up right?

what i'm asking is whats the difference..is the mineral wool going to fall apart? because its mighty cheaper..and it seems like they both have pretty close to the same absorption properties..

would love to pay 36 bucks for 6 2x4x2 panels...that would make 3 2x4x4 traps..i was going to cut holes in the sides as well..

let me know!

should i cut holes in the sides of the ones that are going in the corner?
or just the ones that are going to be used on the wall behind my monitors..as broad band absorption panels?

let me know guys, i'm sure you've heard these questions 100 times..

[Cojo]

Hi xmostynx.

I'm not really sure I follow you...

If the mineral wool is rigid enough it would hold up on its own and wount fall appart. Regarding the holes in the frame; - How deep are you going to make them?

If they are 4" or less it might be difficult, if they are thicker - go for it.

I made my 4" traps with just a tiny frame on the back so the full sides are exposed. I can take a picture of them tomorrow if you like?

Good Luck!

[xmostynx]

cojo...man thanks so much first for being sucha big help on this thread..

soon everyones rooms are going to be filled with these traps!!


i'm going to make the frames maybe 6 inches deep, so when i can save up some more cash i can stuff 2 more inches of SAFB Mineral Wool 2-inch..

thats what i'm going to go with from this website..unless someone has a better suggestion..

http://www.atsacoustics.com/item--SA...f-6--1006.html

I was gonna copy your design, with the side cuts, instead of using a jig saw tho.. i was going to get a circular drill bit, and just go to town with 2inch and 1 inch holes..
kinda just pepper the sides..

so i'm thinking, 2feet wide, 4 feet long, 6 inches deep, stuffed at first with 2 inches of mineral wool, 2 inches open space, 2 inches mineral wool.

and then next month i could stuff them with an extra 2 inches. leaving the back of the traps open so i can easily stuff some more insulation in.

i was wondering if the SAFB mineral wool was going to hold up, or just clump up..

then...i was wondering, i can use the traps i'm going to build (9 in total) and i can place them (3 of them behind the monitors, on the wall, 1 to the left wall, 1 to the right wall, 1 to the back wall, then 3 in the corners of my room)

then next month maybe i can build another 9 to finish up the room...i'm assuming since my mixing space is tiny, and it doubles as my bedroom with a queen size bed and all of my girlfriends freaking clothes.. that 9 traps to start off with are going to make a huge difference..(i have movers blankets up now)


haha thats an ear full..but mainly..

SAFB mineral wool hold?
the 703 breaks my back..and i could only make like 3 to 5 traps instead of 9..

let me know...i could always save up and put a piece of 703 in the middle?

do let me know..

[xmostynx]

shipping is like 56 dollars..

i would like to pick it up locally..where would i find this tho in the city?
for an extra 56 dollars...thats more insulation! haha

[Cojo]

Hi xmostynx.

Using a hole saw to cut the holes would be great but remeber to hold the drilling machine steady!

I was checking out the SAFB. Here is a citate from ats acousic:

"SAFB is flexible, like dense household insulation batts. It does not hold it’s shape like rigid fiberglass board (such as Owens Corning 703). SAFB is suitable for acoustic insulation inside walls, building into panels, or any place where there is a frame or structure to attach it to."

So I guess that answers your question if it holds its shape or not.

And Yes, it's probably better to pick up the insulation in a local store.

[Cojo]

Here is some pictures of my 4" traps.

I have just made a light frame of two 15x15x120mm and two 42x15x56mm. I used the broader one on the short sides to make the frame a little sturdier. I glued and nailed them together.

Then I stapled the back side fabric and put two 2" insulation slabs on top of it so that the fabric comes in between. I then secured the insulation with gaffa tape on each end.

After that I streched fabric around the hole trap and stapled it on the backsides while folding the fabric.

Also Before I put on the fabric I screwed two "iron angles" <-- don't know what they are called in english, on the bottom short side to prevent the slabs from sliding down.

Hope this it to any help.

[xmostynx]

cojo you do some nice stuff.wonder how your mixes sound!

i just figured out some basics from home depot here in pittsburgh..

if the guy wasn't bullshitting me on the phone
i can get owens corning 703 1 inch thick for about 47 dollars for 155square feet..

to sum it all up, to make the traps i want i'm going to be spending around 100dollars for all my insulation to make my traps 4 inches of insulation thick..

if i dont' have to mix sunday night...thats the night to build!!!!!

[Glenn Kuras]

Originally Posted by xmostynx

shipping is like 56 dollars..

i would like to pick it up locally..where would i find this tho in the city?
for an extra 56 dollars...thats more insulation! haha

you may get a couple ideas off of this thread

http://gearslutz.com/board/showthread.php?t=101748

Glenn

[xmostynx]

very cool myfipie thank you!

[daveyDAVE]

Good job with those traps man.