"Cosmetic" Front for a Bass Trap...

[camistan]

Greetings!
I was reading in a post...(Page 2 about 1/2 way down)

http://www.johnlsayers.com/phpBB2/viewt ... c&start=15

where Ethan says...

With bass trapping, the more the merrier. While you can definitely make a room too dead sounding at mid and high frequencies, I don't think it's possible to have too much bass trapping. In fact, I'm sure of it. I have 40 traps in my living room, and every time I added more the low end continued to get flatter and tighter - both audibly and measurably

Below is a design of my control room. I am planning on putting Helmholtz resonators on my side walls and was going to put basic broadband (mid to low) corner traps in the rear corners of my studio. I was wondering though...

1.) Since the lower frequencies gather more at the rear of the room, would it be better to make the whole rear area a bass trap using insulated wrapped panels as in the pic below?

2.) If I did this would it take away from the effectiveness of the bass trap
to have the front designed like the 3rd drawing (which looks like the assembly might be a diffusor)...with thin vertical strips going down the upper two-thirds of the trap and boxed areas under those? This is only for cosmetic reasons, but if I were to build one continuous bass trap, this seemed like a nice "front" as long as it didn't diminish the trap's performance abilities.

[gullfo]

actually bass is reinforced in all corners of the room including the vertical corners and the wall-ceiling and wall-floor horizontal corners as well. typically control rooms have more bass trapping in the rear of the room because its where you usually have some more space and most times it is combined with absorption and diffusion to reduce significant reflections back to the mix position. having decorative panels or diffusers not only help keep more life in the room by not trapping too much of the high frequency energy, but in some cases, add additional bass trapping effects by acting as panel traps (probably more luck than not, unless designed for it) and somewhat as impedence on returning waves by restricting the air between the two spaces (room and trap). the studio rear photo is not only nicely finished but has plenty of trapping and a diffuser (assuming the space can take advantage of it - a long CR can) to keep it from being dead sounding.

[Ethan Winer]

Below is a design of my control room. I am planning on putting Helmholtz resonators on my side walls

Since there are no dimensions on your drawing it's impossible for me to comment. But I will say that broadband, not tuned, bass trapping is generally the better choice.

> Since the lower frequencies gather more at the rear of the room, would it be better to make the whole rear area a bass trap using insulated wrapped panels as in the pic below? <

Corners, corners, and more corners. Then the back wall.

--Ethan

[camistan]

Gullfo:Thanx a LOT for the response! Those are points of interest you wrote about and I appreciate the info!

Ethan, thanx a lot for your response also! Below are the dimensions for the room. I hope this is helpful for your evaluation. Please let me know your opinion of whether the picture of the studio rear would be ok to use as a FRONT DESIGN for a bass trap using the suspended panels as I stated in the previous post. The striped area behind the corner absorbers could be used entirely as a bass trap if you see fit. Do you think a diffusor would be adequate for the rear? The corner absorbers would be built as per the standard corner design listed on this site.

I wanted to have "some type of front other than a big long sheet of material covering Rockwool/mineral fiber. However, my main concern is to have the absorbers/traps to function at their peak capacity whether there is a "front" design or not

Thanx!

[sandledfoot]

hey stan,

what is the middle layer in the hanging bass traps ??

I saw in the reference forum on the sae site that its listed as fiber board... but not sure I know what that material is being referred to?
A. MDF (
B. plywood or chipboard
C. OC 703
D. None of the Above

if I had to guese, it would be chipboard... but i'm not sure!

also... what thickness of the board, and insulation are you using?


btw... the last picture (rear control) looks really good, even if you clone the wood dividers effect, and screen the rest with some cloth material... i'm assuming the middle panel was acting as a diffuser...

cheers
kevin

[Ethan Winer]

Please let me know your opinion of whether the picture of the studio rear would be ok to use as a FRONT DESIGN for a bass trap using the suspended panels as I stated in the previous post.

I'm afraid I don't know what you're asking.

--Ethan

[camistan]

Ethan...
Most of the designs I've seen for a bass trap only have a solid cloth front. In the ORIGINAL picture in my previous post, the picture looks as if all the TOP assemblies are diffusors. The areas under the diffusors are sectioned off instead of it being one continuous cloth front.

What I was proposing to do was to build a bass trap that had a FRONT design like the picture. Instead of diffusors (if that's what it is) being on the TOP, I would have an assembly with thin wooden strips, (SIMILAR to a diffusor) cloth right behind the thin wood strips, THEN the bass trap panels (hanging & wrapped in insulation). The bottom sections would still look exactly like the picture.

All I wanted to do was to have an assembly FRONT that "cosmetically" would look better than a solid cloth front. No matter whether it's the "FRONT" I am questioning about, or a solid CLOTH front, the hanging bass absorbing panels would be behind EITHER assembly. Simply put, there would only be the extra WOOD you see in the pic in front of a cloth covered bass trap with hanging panels.

I do plan to put corner absorbers to the right and left of the bass trap assembly as shown in the dimension drawing in my previous post.

BTW, I went to your web site and saw the plans you had for a deep bass trap and a high bass trap. I could build that design instead of having hanging panels. Unfortunately, I couldn't make out the words in the drawing. (Do you have a more clear design I could print?) For me, which ever bass trap (your design or hanging panels) is the MOST efficient and takes up the LEAST space, that's the direction I want to go!

So...with all this said, my question for you is if I build a bass trap FRONT designed as I described in this post, would THE DESIGN affect the efficiency of the bass trap?

I tried as best I could to illustrate what I mean in the picture below. I modified the original bass trap pic so you could see what I'm talking about a little better.

Thanx for your help and I hope this post makes things more "understandable".

[camistan]

Hey Sandlefoot,
Man, I'm nodding off as I write this...I'll let you know about the materials tomorrow. Right now I'd tell you they were made out of a shoe as sleepy as I am...

[Ethan Winer]

[quote="camistan"]All I wanted to do was to have an assembly FRONT that "cosmetically" would look better than a solid cloth front.[quote]

I don't know what else you'd put in front of the fiberglass besides cloth. I suppose you could use card stock (very heavy paper) or cardboard. Either of those will let bass pass through to be absorbed by the fiberglass behind. Then you could paint the cardboard to look like painted sheet rock, or you could paint any pattern etc you want.

> I went to your web site and saw the plans you had for a deep bass trap and a high bass trap. I could build that design instead of having hanging panels. Unfortunately, I couldn't make out the words in the drawing. <

That drawing is clear, but maybe your browser is resizing it? Try saving the Plans detail GIF file and viewing it separately.

> if I build a bass trap FRONT designed as I described in this post, would THE DESIGN affect the efficiency of the bass trap? <

Wood is okay if it's placed perpendicular to the wall like the well separators in a diffusor. But if it's flat against the wall it will reflect bass which you don't want. Maybe really thin balsa wood would be okay flat on the wall.

--Ethan

[John Sayers]

Camistan - the far corner of this room is a hanger trap and the slot resonator is built on the front, it has a depth to the back of the front stud frame, behind it is hangers.

Is this what you had in mind?



cheers
john

[camistan]

Ethan,
Thanx for the info! I'll most likely be building a bass trap as I've stated in these post and I'll use your recommendations in making it. It sure would (in my opinion) look a lot nicer than straight cloth travelling across the distance of my control room rear wall as shown in the dimension post above.
Thanx!


John...Oh Yea!
Yes, that's the idea I'm talking about John! As I said, it's basically a small amount of wood in front of a bass trap. Looks like the person who did that went to a higher level of a resonator-trap than I anticipated could be done!
Thanx-a-LOT!

[John Sayers]

Stan - it will work in your room because you have a long control room of 19'+.

Other readers of this thread should note that if your room is shorter it's not a good idea. The distance from your listening position to the rear of the room and back again, i.e the distance a wave front will travel when it's reflected from a rear unit such as this - must be greater than 18 - 20 feet, which in Stan's room it is.

cheers
john

[camistan]

Hmmmm....
After "browsing" a bit I found this post...
http://www.johnlsayers.com/phpBB2/viewtopic.php?t=5628
According to Steve, the resonator front would conflict with the bass trap rear. I guess that design is a no-go...(the resonator front)

[camistan]

Ok Sandlefoot...

My SINCERE apologies for not getting back to you more quickly. As of right now I haven't built my bass trap yet. That pic was from another studio. I was just using it as an example. I may not even go the route of having those panels. I went to Ethan's site and downloaded info on his deep bass trap. I wondered though, which trap is better...the hanging panel trap or the plywood front trap? I asked that in a post in this forum...I guess we'll see!

Anyway, here's a post that will answer your question about the materials for the hanging trap...
Hope this helps!

http://www.johnlsayers.com/phpBB2/viewt ... =bass+trap

[sandledfoot]

Perfect!!!

no worries about the "late" post... i'm a bit of ways out from addressing the acoustics... just trying to get ahead of the game a bit.

Thanks Stan!

kevin