Bass Trap build and positioning help needed!`

Ok, the next project on my list is building a bass trap... I have read a ton of info on the web and am ready to build a few of these myself.

I would like to build a 8' x 2' trap that I will place across each front corner with airspace behind it. I may use what I used on my wall panesl (Armstrong 1" ceiling tiles out of fiberglass with the vinyl backing removed or I may try to find a local owens corning dealer and get 703 0r 705).
My plan is to make each trap 4-6" thick. I have a few questions here:

1.) How important is it for the trap to be floor to ceiling? I have read that it is best to have it cover the whole heighth. I have my JL Fathom sub in the corner and if I place a trap in the corner it will take away a bit of floor space and will cause me to have to move the sub out of the corner to the left... How will this affect the bass performance by moving the sub away from the corner by a foot or so??? Or should I just make the panel go from the ceiling to the top of the sub and leave the sub tucked in the corner??? This is my biggest quesion...

2.) as for the frame, I do not want to build a bulky 2x4 frame around the trap, any other interesting low profile frames / supports people have used? I saw someone use metal corner bead and that looks pretty promising...

3.) Should I put polyester batting between the fiberglass and my fabric?

4.) I have a mid/high absorption panel on either side of my screen, and that leaves only a couple of inches of exposed drywall to the intersecting side wall. When I hang the traps in the corners, should I remove the existing 3" Fiberglass panels so I just have pure drywall in the actual corners or will it not matter that there would be a 3" panel behind the bass trap on one side?

My equipment rack is in the front left corner. the rack opens into a little storage closet. Could I use this closet since it is somewhat open where the equipment is, as a bass Trap by putting a few bales of insulation in plastic in there? Would it have any effect?

thanks alot for everyone's help!

gordon

My room is in the basement, and is about 17' wide by 38' long (it opens into a kitchen area). Total volume about 5,000+ cubic feet! I will also be adding a second Fathom sub next week...

I have attached a couple of pics again of my front wall of the HT.

Gordon,
First of all what a fab. room.:bowdown: I have been wanting a place like that forever. I am not really qualified to help in this project, but would ask if you could resize your pics. I'm sure more folks would jump on to help, if the post was easier to read. On my puter all I do is size the pics at medium size and medium quality and all is good.
Hope everything works out for you, and again that room and equipment is awesome:rocker:

Doug - out

Doug, thanks for the compliments and suggestion about resizing... I had all pics at 800x600 except for one that I just resized... Is that still too big?

The picture that shows my equipment rack and subwoofer (Snell sub 550 THX) will have the sub replaced soon with a second JL Fathom 113. Since this sub is not quite as tall, the sub could theoretically be placed a bit to the right and still not interfere with the screen if I decide to take the bass panel from the floor to ceiling .

gordon

gordonmenninger said:

Doug, thanks for the compliments and suggestion about resizing... I had all pics at 800x600 except for one that I just resized... Is that still too big?

Click to expand...

Perfect job my friend. Now, happy hunting for your answers. I wish I could help with your issue but I'm not allowed an opinion on this; insufficient data on my part.

Doug - out and good luck.

Gordon, you seem to have a good handle on what to do so I'll address only this:

gordonmenninger said:

How important is it for the trap to be floor to ceiling?

Click to expand...

Bass trapping is all about surface coverage. The more corner space you treat, the flatter and tighter the bass will be. It's that simple.

--Ethan

Ethan Winer said:

Gordon, you seem to have a good handle on what to do so I'll address only this:



Bass trapping is all about surface coverage. The more corner space you treat, the flatter and tighter the bass will be. It's that simple.

--Ethan

Click to expand...

thanks Ethan for all your input here. Well I guess that means I am making the panels floor to ceiling! Thanks.

gordonmenninger said:

Ok, the next project on my list is building a bass trap... I have read a ton of info on the web and am ready to build a few of these myself.

Click to expand...

Great project Gordon!
This should transform your room a good bit.

gordonmenninger said:

I would like to build a 8' x 2' trap that I will place across each front corner with airspace behind it. I may use what I used on my wall panesl (Armstrong 1" ceiling tiles out of fiberglass with the vinyl backing removed or I may try to find a local owens corning dealer and get 703 0r 705).
My plan is to make each trap 4-6" thick. I have a few questions here:

1.) How important is it for the trap to be floor to ceiling? I have read that it is best to have it cover the whole heighth. I have my JL Fathom sub in the corner and if I place a trap in the corner it will take away a bit of floor space and will cause me to have to move the sub out of the corner to the left... How will this affect the bass performance by moving the sub away from the corner by a foot or so??? Or should I just make the panel go from the ceiling to the top of the sub and leave the sub tucked in the corner??? This is my biggest quesion...

Click to expand...

I agree with Ethan, floor to ceiling.

As for moving the sub, often a corner placement over-emphasizes certain frequencies. If you could post a floor plan, I might be able to suggest some options. But I also recommend reading up on subwoofer placements.

gordonmenninger said:

2.) as for the frame, I do not want to build a bulky 2x4 frame around the trap, any other interesting low profile frames / supports people have used? I saw someone use metal corner bead and that looks pretty promising...

Click to expand...

I used some slick metal frames for these guys:
http://www.readyacoustics.com/index.php?go=products.chameleon-acoustic-frame

The 2’x4’side wall treatments on the rear part of my room are edged with this.

gordonmenninger said:

3.) Should I put polyester batting between the fiberglass and my fabric?

Click to expand...

Your call, but I would on the faces that will be directly struck by the direct radiation of an ESL panel.
That extra bit of HF absorption is noticeable.

But it’s not worth doing if they are off in a corner and the direct or even once-removed reflections won’t hit them.

gordonmenninger said:

4.) I have a mid/high absorption panel on either side of my screen, and that leaves only a couple of inches of exposed drywall to the intersecting side wall. When I hang the traps in the corners, should I remove the existing 3" Fiberglass panels so I just have pure drywall in the actual corners or will it not matter that there would be a 3" panel behind the bass trap on one side?

Click to expand...

I’d leave it as-is, the extra 3” won’t hurt and probably might even help a bit

gordonmenninger said:

My equipment rack is in the front left corner. the rack opens into a little storage closet. Could I use this closet since it is somewhat open where the equipment is, as a bass Trap by putting a few bales of insulation in plastic in there? Would it have any effect?

thanks alot for everyone's help!

gordon

My room is in the basement, and is about 17' wide by 38' long (it opens into a kitchen area). Total volume about 5,000+ cubic feet! I will also be adding a second Fathom sub next week...

I have attached a couple of pics again of my front wall of the HT.

Click to expand...

Not sure about the closet and whether it could be used to soak up more bass. All I can say is if it’s just a matter of throwing in some bales of insulation and measuring the effect, then do it.
But you should measure.

I hope your enjoy the process, I’m sure the results will be worth it.

Jon,
yes those Ready acoustics frames look very slick! I may have to try some of those one of these days!
Well, I build 2 floor to ceiling traps, and used the design that i found here
http://www.radford.edu/~shelm/acoustics/bass-traps.html

I bought a rivot gun from home depot and also bought all the metal corner bead there ( a bit different than in the pic, but still ok). I took a few pics but they are pretty much the same as in his post. I wrapped polyester batting over the metal frame and stretched black "broadcloth" from Hancock fabric over them . Mine are almost 6" thick. They turned out very nice.

Of course i did not practice what I preach to myself all the time: measure twice, cut once! I did just the opposite... The left panel went up fine and fit perfect under the ceiling. I assumed the ceiling height was the same in the right corner----No way ! It was 1" lower. It was already 1 am and I had to take that damn metal trap apart again to make it shorter... I had to finish up because the area where I was working in (basement kitchen) needed to be cleaned up in the morning from the "mess" I had been making all day! My wife thought I was just building a couple of panels the I put behind my couch and covered in red (pics to come)... She did not know I was building these monsters for the corners! Luckily I have a black wall around the screen and she still has not noticed - yet!
I removed the 3" 24x48" panels that I recently made for behind the SL3's and used those to for the rear/ side of the room behind my couch.
Now I just have the 2 Bass traps straddling each corner and a panel below my screen behind the ML Theater center channel.
Oh yes, I also bought a bale of insulation that I put on the floor in my equipment closet... my wife just kept shaking her head when I walked through our gourmet kitchen with metal corner bead, 2 huge boxes of fiberglass ceiling panels, and a huge bale of fiberglass... "all that to make those 2 damn panels"? she said. I just nodded and got busy!

pics later

gordonmenninger,

Thanks for posting this project. I think you will be well rewarded for your efforts...

Looking forward to reading what you think about the difference this makes to the overall sound of your system.

Satch

Pictures

Ok, the project is done! I think it turned out quite nicely (and my wife has not noticed them yet and she notices EVERYTHING!)

I have included a few pictures of the black bass traps in the front corners. They are floor to ceiling and are about 8' high and 24" wide and close to 6" thick. I also but one layer of the synthetic batting over the whole trap before covering it with cloth. Wow, do they make a huge difference they make in the sound! I recalibrated everything again and the bass is alot smoother and the room sounds alot "quieter". The bass seems to just have that little extra low end oomph now. I used the panels I originally made on each side of the screen and have them behind my listening position now. I covered them in red fabric (thanks JonFo for suggesting I let my wife pick out the fabric - that trick worked!). That has helped alot as well as the sound kept bouncing off that wall all over the place... Now all the sound that is supposed to come from the front, comes only from the fronts and same with the rear!
I would highly suggest anyone who can fit one of these traps into their room, DO IT! It is one of the cheapest upgrades you can make in this little expensive hobby of ours! Same goes for the panels on the walls!

oh also note my newest equipment addition in the last picture - my new JL Fathom 113. I liked it so much I ordered one more!

gordonmenninger said:

Ok, the project is done! I think it turned out quite nicely (and my wife has not noticed them yet and she notices EVERYTHING!)...

Click to expand...

Gordon, I just have a minute, but I wanted to be the first to say, WOW! Great job man :bowdown:

That looks great, and your descriptions of the changes sounds like they are effective at their job.

Excellent work.

Thanks Jon! The whole soundstage is coming together now and the Bass is just sooo much more intense in some ways... It sounds like I have more subs in the room and is almost making me think twice now about the second Fathom 113 that I just ordered and already paid for! Nah, what the hell, I love a little excess!!!

JonFo said:

Gordon, I just have a minute, but I wanted to be the first to say, WOW! Great job man :bowdown:

That looks great, and your descriptions of the changes sounds like they are effective at their job.

Excellent work.

Click to expand...

Absolutely awesome looking job Gordon! DIY is the way to go. I wish it were as easy as letting my wife pick the color of the fabric. Let me make sure I understand everything you've done.
1) You built 2'x4' high/mid absorption panels and covered in black for behind the SL-3.
2) Built bass traps, and moved the 2'x4' panels to the rear speakers, and swapped out the fabric to red.
3) Built additional high/mid absorption panels for the rear.

Any plans for more room treatments?

Did you use polyester batting between the fiberglass and fabric on your 2'x4' panels?

Gordon..... as already stated, nice job ! I trully think that DIY projects when succesfull sound better than those bought commercially !!

TrumpetDoug said:

...... but would ask if you could resize your pics. I'm sure more folks would jump on to help, if the post was easier to read. On my puter all I do is size the pics at medium size and medium quality and all is good.

Click to expand...

What he said.

yes, sorry again about the pic size.. I noticed that as well! I already have them sized down to 800x600. What is the proper size for this forum ??? thanks!

Bernard said:

What he said.

Click to expand...

1 and 2 are correct. #3 - I build 5.5" bass traps that are floor to ceiling and placed at an angle across both corners. They (as well as the panels in the rear) both have polyester batting between fiberglass and fabric for additiona high frequency absorption. Also, I used a hot glue gun (and 2 huge packs of glue sticks) to attach fabric and batting to the fiberglass - worked great!
I do not know if I can get away with too many more panels at this time! Room sounds very good now though - I do not want it to turn out too dead either! Oh, and I also have a panel behind the center channel on the floor which makes a HUGE difference as well - Dialogue etc is very clear now as compared to before! It was a fun project and I agree if you take your time, DIY can get you great results!

Brian_74 said:

Absolutely awesome looking job Gordon! DIY is the way to go. I wish it were as easy as letting my wife pick the color of the fabric. Let me make sure I understand everything you've done.
1) You built 2'x4' high/mid absorption panels and covered in black for behind the SL-3.
2) Built bass traps, and moved the 2'x4' panels to the rear speakers, and swapped out the fabric to red.
3) Built additional high/mid absorption panels for the rear.

Any plans for more room treatments?

Did you use polyester batting between the fiberglass and fabric on your 2'x4' panels?

Click to expand...

gordonmenninger said:

yes, sorry again about the pic size.. I noticed that as well! I already have them sized down to 800x600. What is the proper size for this forum ??? thanks!

Click to expand...

800 is a bit too wide; I think a width of 600 is just about right.

Bernard said:

800 is a bit too wide; I think a width of 600 is just about right.

Click to expand...

ok, thanks! I will remember that next time...