How I built my bass traps...

[superiorsound]

What can I use to measure my rooms frequency? I see the spartan graph googled it and cant find anything? What software would I need to figure out what are the troubled frequencies in my room. I plan on building 4 bass traps very similar to what cojo has done. I would like to mesure it first to go after the troubled frequencies which I believe is in the 100-150hz range but cant be a hundred percent sure. Also what is the best insulation to use?

Thanks,

[Cojo]

Originally Posted by jaykay

I wanted the material flush with the front panel so I bought some long thin strips of wood and staple gunned through it into the frame to give a nice edge that is invisible from the outside.



As you can see, nice and flush with the front...



After that part it was a downhill run, I just had to fit the insulation into the frames which was a snug fit as I'd deliberately undersized the frames by 5mm.



After stapling the fabric into the top sides I then decided to just sew the back up, it seemed like the easiest solution at the time and worked out really well.



And that's it. A finished product. I had a real deadline as my wife's 30th was coming up and I'd promised the apartment would be in order by the time that came around. So all in all it probably took me about a month and a half to get them all done, it was really a lot more work than I'd bargained on but definitely worth it in the end.

Very impressive I must say!

[Cojo]

Originally Posted by F5D

Ok, I promised some pics of my new traps, so here goes:

Paroc FPS14 rockwool:


Two frames 1240 x 1240 x 145 (mm)


Two layers of rockwool installed, leaving a 45mm air gap behind:


Wool sealed by very thick felt, ready for finishing fabric:


One of the traps in use at the first reflection point:

Very nice!

[Cojo]

I'm not around here very often anymore but it's very nice to see all of your impressive builds. Keep up the good work guys!

[Weasel9992]

Originally Posted by Cojo

I'm not around here very often anymore but it's very nice to see all of your impressive builds. Keep up the good work guys!

It really is. There's some great looking bass traps in this thread for sure.

Frank

[bibleboy3]

this might be a stupid question but.... I see people using rock wool traps/absorbers what about using 2 layers of 2" thick carpet padding


Bill

[Weasel9992]

Originally Posted by bibleboy3

this might be a stupid question but.... I see people using rock wool traps/absorbers what about using 2 layers of 2" thick carpet padding

That wouldn't work well...wrong density.


Frank

[bibleboy3]

Originally Posted by Weasel9992

That wouldn't work well...wrong density.


Frank

but I thought varying density helps to stop/slow down the wave


Bill

[pittsburgh]

I'm planning on making some bass traps as shown here on this forum. I would like to cut out sections of the wood frame to gain more exposure to the 703. Is there a template or a guide for making the cuts?

[Olevg]

Great thread!
It got me inspired to build some asborbers for my small room. The room measures 4400x3130x2055 mm and here's a sketch I came up with. There's a bed and a closet in the way atm, so I have the panels from the 4th cornerabsorber standing on the bed for now..

I'm going to fill the absorbers with 150 mm thick, 100kg/m^3, rock wool (isover cleantec G8379 Ljuddiagram).

The stands put the non-corner absorbers at a minimum of 90 mm from the wall.

Any suggestions on the material or design before I start?

[rashman]

Originally Posted by Olevg

Great thread!
It got me inspired to build some asborbers for my small room. The room measures 4400x3130x2055 mm and here's a sketch I came up with. There's a bed and a closet in the way atm, so I have the panels from the 4th cornerabsorber standing on the bed for now..

I'm going to fill the absorbers with 150 mm thick, 100kg/m^3, rock wool (isover cleantec G8379 Ljuddiagram).

The stands put the non-corner absorbers at a minimum of 90 mm from the wall.

Any suggestions on the material or design before I start?

If I remember right, 100kg/m^3 is too dense. Correct me if I'm wrong but I remember the proper density to be around 60 to 70 kg/m^3.

[Olevg]

Thanks for your input. I thought a density of 100ish was optimal for low freq absorbtion (in rockwool) but reading through this thread it seems like most people use less dense material. What's the consensus on this?

I wanted to use the OC 705 at first, but OC aparently don't sell those or any other isolation panels in europe. I've been looking all over for suitable replacements and this was the closest match that I could find.

100 kg/m^3:


35kg/m^3:

[Lemonsqueezer]

Unfortunately those graphs don't use the same thickness.

At 150mm thick I personally would save money and go for something like 45kg/m^3.

The thicker you go the less density is needed, up until a point.

[Olevg]

I haven't been able to find anything in between 35 kg/m^3 and 100 kg/m^3 where I live. I'm going to change the design of the frame to fit 120mm of insulation instead of 150mm and stick with the 100kg/m^3 wool. This will save me some dough and make these things some what less massive. Wish me luck!

[F5D]

The Paroc FPS14 wool that I used, is about 66kg/m^3 (roughly measured). Should be available in scandinavia. Isover also have some type of wool that is close to this.

[ari800]

Okey,

Here's mine. These are 35 cm thick, about 1.5 meter high and 60cm wide traps in my small programming room.

Two of them are around my listening position and two in back corners. (the laptop setup is only there for listening the room & doing tweaks to the acoustics... Gear is not in yet also...)

Anyhow. The consept was this : I also have a small tracking room which sometimes needs more bass trapping / isolating / whatever. Since I got my traps on wheels I can simply push them to another room - to do what ever needed to make the recording...

I didn't see anybody doing this, so I though it would be nice to share this idea!

I'm going to put some pictures of the final setup/acoustics as soon as I finish my building...

[networkacid]

Hi all,

Firstly, this is a really awesome thread. Truly in the spirit of what forums like this are intended to be.

Now, I'm about to move into a new room and inspired by this thread am going to build traps of my own. Just a question about corner traps. As they leave a triangular air gap behind them in the corner, would it be beneficial to fill that gap with even more absorbent material like rolled up foam or something like that? Or is it better to leave the gap?

Also, based on what people are saying about tight weave vs. loose weave. Would it be beneficial to use a tight weave fabric on corner traps to skew their effectiveness towards the bass end? I'm guessing the HF reflections off the fabric would be pretty diffuse.

[Lemonsqueezer]

Originally Posted by networkacid

Hi all,

Firstly, this is a really awesome thread. Truly in the spirit of what forums like this are intended to be.

I do love this part of the forum. There's a real good vibe about it.

Things can get a bit heated over converters and pres elsewhere on the forum but you can always come back here where there is much love

[Lemonsqueezer]

Originally Posted by networkacid

Hi all,
Now, I'm about to move into a new room and inspired by this thread am going to build traps of my own. Just a question about corner traps. As they leave a triangular air gap behind them in the corner, would it be beneficial to fill that gap with even more absorbent material like rolled up foam or something like that? Or is it better to leave the gap?

Foam is not as effective as rockwool/fibreglass/mineral wool. If it isn't going to cost anything then it won't hurt and may offer a small improvement. I personally would not buy any for the job though. Another option are the superchunk corner traps. They fill the gap entirly and will improve the effeciency but will make the price escalate and are not as good value. It does come down to budget at the end of the day.

[networkacid]

Yep the traps will be rockwool but I was just think of something cheaper to fill the gap. Thanks

[Weasel9992]

Originally Posted by networkacid

Yep the traps will be rockwool but I was just think of something cheaper to fill the gap. Thanks

Mineral wool or 703 would be better, but foam will do if it's open-cell (like Auralex or the like).

Frank

[networkacid]

Thanks again. I've found a local manufacturer of rockwool panels (CSR) Which are almost perfectly sized (1.9 x 4.4 feet) and optimized for deadening sound - it's made for internal walls - but the thicknesses mean I will likely end up with either a 3'' or 6'' panel. Is 6" too thick? I notice people are generally going for around 4"...

[Lemonsqueezer]

6" will be good

The thicker you go the better for low frequency efficiency.

[Weasel9992]

Originally Posted by networkacid

Thanks again. I've found a local manufacturer of rockwool panels (CSR) Which are almost perfectly sized (1.9 x 4.4 feet) and optimized for deadening sound - it's made for internal walls - but the thicknesses mean I will likely end up with either a 3'' or 6'' panel. Is 6" too thick? I notice people are generally going for around 4"...

6" is definitely NOT too much.

Frank

[betserd]

Let me just drop in some pictures of the basstraps i'm building at the moment.

The traps will be 160cm x 100 x 20cm so they are quite big. They are build out of MDF which was cut into strips of 20cm.
I used a saw to cut out one vertical section and one horizontal section and used the milling machine with a copybit to use the first ones as templates and quickly do the other ones. Then I milled the slots for the horizontal strips to slide in and glued it together.
I do have some pictures of the building itself but they are on a different camera. More pictures will follow as I progress.

[pfo]

Well, I'm intrigued. I'm considering building a few traps myself, but I have a few questions for you experts first.....

-Just so I'm sure I understand.....6" traps will be effective to a lower frequency than 4" traps, and superchunk traps will extend even lower -- correct?

-I assume any brand of rigid fiberglass with the same density as the 703 would work, right?

-I would want to make some semi-reflective traps and some that aren't. If I can only find FSK coated 2" panels, would it work to simply build the traps with the uncoated sides facing out and the coated faces on the inside?

-What about making a trap with FSK on one side and none on the other so that it would be reversible?

-If I decided to go the superchunk route, would the presence of the FSK have any effect on the the trap's performance?

-When making 4" deep traps, would it be better to build a full frame to hold the panels, or would it be ok just to have a frame on the back side and use the tension of the cloth to hold them together? Being that it would be two 2" panels, would they sag over time? I'm guessing that if the FSK surfaces were touching, the panels might slide a bit. Maybe it would be better to peel off the FSK for the uncoated traps?

Thanks, and cheers!

[F5D]

Just ordered more wood and rockwool, picking them up on saturday. I am going to start building 6 new absorbers next weekend. They will be 1200x600x70 (mm) and have 50 mm wool layer inside, leaving 20 mm airgap behind. These are going to be the thinnest traps I have. I will then have a total of 17 bass traps / absorbers in my room if one trap is considered as 1200x600 size.

[BF_]

Originally Posted by pittsburgh

I'm planning on making some bass traps as shown here on this forum. I would like to cut out sections of the wood frame to gain more exposure to the 703. Is there a template or a guide for making the cuts?

I just measured out and marked where I wanted the gaps on the wood, leaving enough material between each to retain some structure. I used a hole saw of the appropriate size at either end of the sections to be removed, then connected each pair with a jigsaw. This allowed me to create a finished rounded edge to each section quickly, and more accurately than I would have cut by hand with the jigsaw.

[F5D]

I started building yesterday. 3 are ready now, 3 more to go. The price per one trap is about 40 euros. One 50-mm rockwool layer inside, 20-mm airgap + felt on both sides + finishing fabric, weight per trap about 8.7 kg.

[pittsburgh]

Originally Posted by BF_

I just measured out and marked where I wanted the gaps on the wood, leaving enough material between each to retain some structure. I used a hole saw of the appropriate size at either end of the sections to be removed, then connected each pair with a jigsaw. This allowed me to create a finished rounded edge to each section quickly, and more accurately than I would have cut by hand with the jigsaw.

Hey BF Thanks a lot. That's the correct answer for sure.