[Tyson]

OK, one thing we talk about getting under control is the room, if you want ultimate performance from your GR Research speakers (or any speakers, for that matter).  I have a dedicate 2 channel and HT setup in my basement using the Super 7 speakers.

Acoustically it's not bad, with thick carpet on the floor and a combo of wood slats (diffusion) and heavy roman shades (absorption) for the windows.  I'd borrowed a friend's GIK acoustic panels as a stop-gap solution until I could build some of my own.  I though it might be fun to share the acoustic panel design and build process.

Here are the wood parts of the panels.  The back is just 1/8th inch particle board from Home Depot.  The black wood that makes up the frame is just 1"x 4" pine boards also from Home Depot.  Obviously I measured everything and then we used a table saw to make the cuts. 







Here you can see the inner wood frame we made that will be covered in black fabric so it matches the colors in my semi-basement HT/Music room:








The linen style cloth and the method of attachment - staple gun!






Clearing out all the furniture from my living room so I have room to work:







Laying out the cloth and measuring it against the wood frame, and then cutting the cloth to size:







Staples.  LOTS of staples:







Frame is ready:







R13 pink insulation from Home Depot.  It's 4 inches thick so it's perfect for my panels with their 4 inch thick side wood panels.  Using spray Gorilla Glue to attach it:








One side in:







All sides in:







Black cloth frame inserted and looking nice.  You might need to use a lint brush to get any hair/lint off before you hang it:







Second panel done.  I did 4 in total:







And done!

[AlexH]

Those look great. I wish I could do that in my room

[Hobbsmeerkat]

That looks awesome, Tyson! Excellent work! 

Thats definitely something I need to work on for my "office" space/spare bedroom now that my housemate has moved out.
Tho for now I've still got 2 speaker projects I need to complete...

[JWCoffman]

Thanks for sharing.  That's one of the next projects to get done once I finish my X-MTM's and X-CS.  What kind of difference have you noticed?

[Tyson]

Alex and Hobbs - thanks!!  Compared to making speakers, building acoustic panels is a snap. 

Thanks for sharing.  That's one of the next projects to get done once I finish my X-MTM's and X-CS.  What kind of difference have you noticed?

Oh, the whole room is much more quiet.  I have no treatments on the back in of my room, so it's a LEDE approach.  That stands for Live End, Dead End.  The back of the room is live (no treatments) and the front of the room is dead (heavy absorption).  This gives the best result for my tastes.  The panels are actually quite massive and because they are so thick, they do an excellent job of killing the first reflection points from the speakers.  So clarity and imaging take a giant step up. 

Also, if you look on the left side, there's actually a big fireplace there.  One of my main goals was to completely cover it, so that the acoustic space on the left side more closely matches the acoustic space on the right side.  And it worked out really well. 

I did experiment with some diffusion panels from GIK but for OB speakers they didn't make a big difference.  That's why I stuck with absorbing panels only.  I think for box speakers you'd probably want more of a mix of absorbing and diffusion. 

[jn316]

Well done, Tyson! I like the different look with the outer frame not covered by the fabric....a frame in a frame. Makes me wonder about my current absorption panels that have different Tuscan scenes printed on the fabric (theater has an overall Tuscany look to it). The fabric currently wraps all the way around the frame to the back. I might toy with enclosing them in an outer frame similar to yours to produce a framed picture look. 

[Tyson]

Well done, Tyson! I like the different look with the outer frame not covered by the fabric....a frame in a frame. Makes me wonder about my current absorption panels that have different Tuscan scenes printed on the fabric (theater has an overall Tuscany look to it). The fabric currently wraps all the way around the frame to the back. I might toy with enclosing them in an outer frame similar to yours to produce a framed picture look. 

Thanks!!  Yes, I really like the exposed wood frame look.  The other benefit is that if you ever paint your room or even move to a new space, all you have to do is remove the inner frame and change it out with new fabric to match the new space.  That's a lot easier to do than when the fabric is wrapped around the outer frame. 

[bernardo]

For any one else with open baffle speakers I recommend using PI Audio ABB1 Diffusers. Danny also recommends them.

I tried Auralex Diffusers and GIK EPS Q7D diffusers behind my Super 7's with poor performance. The PI diffusers work very well.

[jn316]

Thanks!!  Yes, I really like the exposed wood frame look.  The other benefit is that if you ever paint your room or even move to a new space, all you have to do is remove the inner frame and change it out with new fabric to match the new space.  That's a lot easier to do than when the fabric is wrapped around the outer frame.

Nice project to do on a weekend like this...enjoy the snow!

[PDR]

Nice Job!

You can tune them by keeping them away from the wall a bit, try an inch at a time till you get it just right.

Another trick is to try a reflective sheet before the insulation if you find your absorbing to much high end.

I've been using a QRD for years on front wall of my OBs.....its the best improvement to my room ever.

The only other thing I might suggest is covering the first reflection point on the ceiling.....

[corndog71]

I got cheap diamond pattern diffuser panels from Amazon and made a panel for the middle of the front wall and placed the rest at the first reflection points of the rear sides of the Super 7.  I put ATS acoustic panels at the first reflection points for the front side of the speakers as well as across the front corners.  I still think I could use more diffusion but right now it’s sounding pretty good in a small bedroom.  I already learned that you can have too much absorption.

[Tyson]

The other thing I forgot to mention is that having black cloth on the side walls actually increases contrast on my projector screen because less light is bounced from the walls onto the screen.  So here it's a video and audio improvement in one.

[JWCoffman]

Alex and Hobbs - thanks!!  Compared to making speakers, building acoustic panels is a snap. 

Oh, the whole room is much more quiet.  I have no treatments on the back in of my room, so it's a LEDE approach.  That stands for Live End, Dead End.  The back of the room is live (no treatments) and the front of the room is dead (heavy absorption).  This gives the best result for my tastes.  The panels are actually quite massive and because they are so thick, they do an excellent job of killing the first reflection points from the speakers.  So clarity and imaging take a giant step up. 

Also, if you look on the left side, there's actually a big fireplace there.  One of my main goals was to completely cover it, so that the acoustic space on the left side more closely matches the acoustic space on the right side.  And it worked out really well. 

I did experiment with some diffusion panels from GIK but for OB speakers they didn't make a big difference.  That's why I stuck with absorbing panels only.  I think for box speakers you'd probably want more of a mix of absorbing and diffusion.

Thanks.  Good to know about the absorption/diffusion differences between OB and boxed.  I was planning on including a mix of diffusion and absorption, so this keeps me on track.  Glad to hear you're happy with the results.

[Tyson]

One thing that might mitigate my advice is how far are the speakers from the side walls.  Mine are very close to the side walls, so I absorb as a way to combat VERY early sidewall reflections.  If your setup has more space between the speakers and the side walls, then a mix of absorbing and diffusing might still be the right approach. 

If you do decide to try diffusion, then the PI Audio ABB1 Diffusers mentioned by bernardo are excellent.  And not too expensive.

[mkrawcz]

I like that exposed frame look. I might have to re-due mine behind the Oticas. I used some pine board to make the frame, cloth, and medium density foam. I wonder if the fiberglass insulation works better?

[Shives]

Beautiful rooms, and awesome tips for some room treatment! Was just saying in another post that you can DIY them!

Wicked post, should be a sticky!

Also, another tip for those who don’t have table saws. Measure your needs, and have depot cut them for you! I don’t know if all stores still offer this, some do. Also other lumbar stores in your area. We have a local place that will cut all of your needs, 1.00 a single cut of for a bunch they do a deal. An idea to consider for some!

[Jaytor]

Nice Job Tyson.

In general, if you are starting out with room treatments, I'd recommend being careful not to over-dampen. When I did my first listening room many years ago, I used the live-end dead-end concept and found the resulting sound to be totally lifeless. I ended up stripping everything out and starting over.

I'd recommended doing a little at a time, starting with some absorption at the first reflection point - particularly of you have your speakers close to the side walls as in Tyson's case. After that, add a just a little at a time. Diffusion will almost always help and it's hard to use too much but there is a case for absorption as well, particularly if you have a fairly live room (lots of hard surfaces and/or windows), or if you have room surfaces near the speakers (this includes the ceiling).

I ended up with a rug with thick pad on my tile floor, some modest absorption panels on the cinder-block walls on the side walls behind the speakers, absorption panels on my slightly low ceiling (7'9"), bass traps with diffusion panels on the front wall, and art panels with scatter plates on the side walls in front of the speakers.

[emailtim]

Nice Job Tyson.

In general, if you are starting out with room treatments, I'd recommend being careful not to over-dampen. When I did my first listening room many years ago, I used the live-end dead-end concept and found the resulting sound to be totally lifeless. I ended up stripping everything out and starting over.

I'd recommended doing a little at a time, starting with some absorption at the first reflection point - particularly of you have your speakers close to the side walls as in Tyson's case. After that, add a just a little at a time. Diffusion will almost always help and it's hard to use too much but there is a case for absorption as well, particularly if you have a fairly live room (lots of hard surfaces and/or windows), or if you have room surfaces near the speakers (this includes the ceiling).

I ended up with a rug with thick pad on my tile floor, some modest absorption panels on the cinder-block walls on the side walls behind the speakers, absorption panels on my slightly low ceiling (7'9"), bass traps with diffusion panels on the front wall, and art panels with scatter plates on the side walls in front of the speakers.

Nice listening room !!!

[lokie]

Guys- Thanks for posting pictures.
Can you explain what frequencies your trying to manage with the various panels?

[emailtim]

Guys- Thanks for posting pictures.
Can you explain what frequencies your trying to manage with the various panels?

If you measure your room, you can identify where the problems occur and verify they have been addressed after treatment.

Here is an in-room measurement of a left speaker (tall line array).  The room reflections can be seen in various plots types.  The reflections from the left speaker can be different than the reflections from the right speaker so they should be tested individually.

The IMPULSE RESPONSE depicts 2 reflections as peaks but gives no indication as to the frequencies causing them.  The first appears @ 4ms and the second @ 9.4ms.



The corresponding vertical Spectrogram depicts these same 2 reflections as light blue vertical bars from @ 1kHz and up at the same 4ms and 9.4ms times.



By placing a quilt at one side of the mic or other and then working outward, you can identify where the reflections are coming.

Both of these reflections were identified to come from the left speaker.  The 4ms was the left side wall.  The 9.4ms was the right crosswall reflection coming from the left speaker (NOTE: left speaker reflections were hitting both sides of the mic). 

NOTE: A rough rule of thumb is that 1ms equates to @ 1 foot in distance so a 4ms reflection indicates that reflection pathway traveled @ 4 more feet to reach the microphone than the direct sound.  9.4ms indicates the reflection path took @ 9.4 feet more than direct sound.  These distances can also give you a clue as to where they are coming in your room.

Once properly treated, these peaks and bars should be depicted as attenuated in the corresponding "after treatment" measurements.  If not, the treatment didn't address the specific issues.

Here is an example of 1st reflections coming from a left speaker (minus the floor and ceiling reflections).  Notice the left sidewalll and right cross-wall reflections coming from the left speaker are the same 1st reflections as measured and depicted in the IMPULSE RESPONSE and SPECTROGRAM plots.