a few questions regarding acoustic panels

[pjoseph]

The main reason I am building panels is because I want to level out the bass in the room, I love the loudness of the bass which is located closer to the walls of the room and as you move in closer to the center of the room it seems to die down.
I plan to first target the first reflection point with a few 4" panels.

I want to cover the acoustic material only with fabric but not the frames that I am building, I plan on painting them, I was thinking that in order to compress the material down some since it will be 4" and the wood that I found at home depot although says 4" really is only 3.5".
So I plan on putting a thin back on the panels and leaving a slot on both the left and right side to pull the fabric through and glue it to the back. This will allow me to pull the fabric tight and compress it to give me a flush front.

From reading around it seems like it is better to have an open back but I really am not sure how I could compress the material down without including the frame or putting a back on it.

So I wanted to ask if there will be a big difference between a panel with a back vs one without a back?

Is mounting a panel with no back on the frame only improve performance if it is mounted with an air gap? I was thinking that a panel with and without a back that is mounted with no air gap would be essentially the same?

Would drilling holes through the back help any if I use like a bit like one would use to drill out a door knob?

Any input would be appreciated Thanks

 

[robc1976]

The main reason I am building panels is because I want to level out the bass in the room, I love the loudness of the bass which is located closer to the walls of the room and as you move in closer to the center of the room it seems to die down.
I plan to first target the first reflection point with a few 4" panels.

I want to cover the acoustic material only with fabric but not the frames that I am building, I plan on painting them, I was thinking that in order to compress the material down some since it will be 4" and the wood that I found at home depot although says 4" really is only 3.5".
So I plan on putting a thin back on the panels and leaving a slot on both the left and right side to pull the fabric through and glue it to the back. This will allow me to pull the fabric tight and compress it to give me a flush front.

From reading around it seems like it is better to have an open back but I really am not sure how I could compress the material down without including the frame or putting a back on it.

So I wanted to ask if there will be a big difference between a panel with a back vs one without a back?

Is mounting a panel with no back on the frame only improve performance if it is mounted with an air gap? I was thinking that a panel with and without a back that is mounted with no air gap would be essentially the same?

Would drilling holes through the back help any if I use like a bit like one would use to drill out a door knob?

Any input would be appreciated Thanks

You want the gap to me almost as thick as the panel unless you get into 8" thick bass traps (I have several of these) here isa pic of what I am talking about (This is the back of the 242 panel from GIK).

 

[robc1976]

For bass control that dips down VERY low I would suggest these in all corners:

Tr-traps:

GIK Tri-Trap. GIK Acoustics. Acoustic Panels and Bass Traps.

I don't know the size of your room but depending on size and other factors you may need 2 subs to get a equal sub response through out the entire room.

 

[robc1976]

Are you putting these panels at 1st/2nd reflection points on walls and ceiling?

 

[pjoseph]

Thanks for the replies

Ok now I think I will make deeper frames this way I can incorporate a air gap in the back and not have to worry about compressing the material to lay flush.

Robc1976
On the back side of the panel you posted what kind of material is the back made of?

I will be placing the panels at first reflection point first, not sure where I will place the rest. ceiling is out of the question for now.

For now I will be making 3 4" Panels to start, but I am sure it will not stop there and I will be adding more in the future.
There is a local place that I found to pick up the acoustic material from for a good price so I can always pick up more in the future.

Thanks again

 

[robc1976]

Thanks for the replies

Ok now I think I will make deeper frames this way I can incorporate a air gap in the back and not have to worry about compressing the material to lay flush.

Robc1976
On the back side of the panel you posted what kind of material is the back made of?

I will be placing the panels at first reflection point first, not sure where I will place the rest. ceiling is out of the question for now.

For now I will be making 3 4" Panels to start, but I am sure it will not stop there and I will be adding more in the future.
There is a local place that I found to pick up the acoustic material from for a good price so I can always pick up more in the future.

Thanks again

I actually had these made by GIK...but they do have do it yourself material...I think it is the same as the burgundy material but just in white. Here is a link to the material they have...also they will help with your room (talk to Bpape). I have 8" traps spaced 6" apart on the back wall, 6 panels at 1st/2nd reflection points on the ceiling, 3 panels on each side of MLP for 1st/2nd reflection points, 1 panel behind my fronts (plan on making the entire front walll dead to minimize surround reflections going to MLP from front). I have 2 QRD diffusors on back walll and will be putting 2 more QRD diffusors at rear of sidewalll to bring up the surround field. If I where you I would make sure to trap the corners...that will really help the bass....actuallly amazing the difference the tri-traps made.

To find reflection points:

For ceiling reflections basically measure from each seat to the the speaker, take 1/2 the distance and that is your reflection point. For sidewalls you need 2 people....sit in MLP and have someone run a mirror across the side wall and when you see the speaker that is the reflection point...1st reflection point will be the speaker closest to the wall, 2nd reflection will be the speaker usually on the other side of the room.


here is the link:

GIK Acoustics. Acoustic Panels and Bass Traps.

GIK Acoustics. Acoustic Panels and Bass Traps.

 

[pjoseph]

I think i need to read up on reflection points any good articles?

Did you mean "Wall closest to the speaker" for the first reflection point?

thanks again

 

[robc1976]

I think i need to read up on reflection points any good articles?

Did you mean "Wall closest to the speaker" for the first reflection point?

thanks again

Yep, basically say you have 5.1 system and are sitting in MLP the right speakers 1st reflection point would be the right side wall, the 2nd reflection would be from the left speaker. Usually they are actually pretty close together....if you have a 9.1 system it can be quite confusing here is mine when I was using foam (terrrible stuff) LOL!! Keep in mind if you only want one good seat do this from the middle seat of MLP...I suggest doing this to all seats. So you would get your reflection points from middle seat, then go to the next seat and so on..

 

[robc1976]

Also try moving your MNLP yo 38% of the room....this really helped my bass response...this is not a "Rule" but works a lot of the time.