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I am very curious as to how the denim works out... I have it stuffed in my soffits, and another bag or two behind my screen.
 

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Discussion Starter #22
It has been an entire week since the last post. That is how slow I am at the upholstery attachment process. And only 1 of the 4 panels is done. Such is the world of DIY, you can get tripped up by the littlest thing.

No doubt there are a thousand guides for upholstery work online.:huh:

A finished frame with two trimmed Knauf panels in place.
IMG_20161106_151514a stuffed frame 1.jpg

A side view. You can see the two Knauf panel thicknesses in this photo.
IMG_20161106_151627a stuffed frame 2.jpg

Another side view.
IMG_20161106_151706a stuffed frame triangles.jpg

On a couple of the frame end-pieces, small cracks appeared where screws were inserted. A little wood glue and a C-clamp took care of that!
IMG_20161106_152306a crack & clamp.jpg

With the upholstery cut into 4 pieces, one section was spread out and the first panel placed on it face-down.
IMG_20161109_033155a on bed.jpg

Jo Ann's Fabric and Craft store had the upholstery tack strip. The other local hobby & craft stores did not.
IMG_20161109_033511a upholst tack strip.jpg

The tools and the process. This photo shows about a day's worth of work.
IMG_20161109_050744a stapled edge.jpg
 

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Discussion Starter #23
ALMOST DONE!

First I gotta admit that for me a DIY project ends up being a little like parenting. Four panels -- four kids. For the first panel, everything had to be perfect. By the time I was finishing the fourth panel, I just wanted it done and out of the way already! Write when you get work! But I digress...


The Wall. This wall has been through so many changes and transitions over the last four years, wish I had pics of every phase. I could make a fun time-elapse mini movie of the development process. All these will be forgotten, "like tears in the rain," sniff... Seriously, it has been a university of acoustics design down here in the Vibratorium. And it is exciting to be having it draw close to fruition. Notice I did not say done. Nothing is ever done down here.
IMG_20161124_124031a-blank wall.jpg


With two panels completed, time to add treatment to the wall itself. Since the GIK panels are destined to stand at an angle relative to the wall, I long ago decided to add some batting to the wall itself behind the panels. The second layer on the wall itself will add to the bass absorption. Rather than killing specific room modes, like we do with a tuned trap, the goal is mainly to dampen out the vibrations at those frequencies so the bass is tighter and SS&I improved. The Proof of Concept had already shown this to be a very effective strategy. Here are the two already finished panels, ready for the next step.
IMG_20161124_144356a-ready to stuff wall.jpg


A simple framework will hold the batting in place. The vertical wood pieces will clamp it against the wall, letting it fluff loosly at middle and ends.
IMG_20161124_194313a-frame on wall.jpg


Working on getting the batting into place.
IMG_20161124_200912a-stuffing the wall.jpg


The wall frame and batting as planned.
IMG_20161124_202402a-wall stuffed.jpg


The vertical clamping bars did not quite snug all the way down, that would have been too tight. Not to worry, though, that bating is not going anywhere.
IMG_20161124_202704a-screw depth.jpg


Getting ready for a listening test with the first two panels.
IMG_20161124_204202a-wide angle.jpg


I have ordered an additional yard of the same fabric from GIK to dress up the wall frame. It will look much nicer! With the batting in place on the wall, the two finished panels were set up for a quick test. The song that had been going through my head - Sleep Is Wrong - Sleepytime Gorilla Museum - was first played. Sounds good! But - So Far Away - Dire Straits - and - Black Hole Sun - Soundgarden - were far better demo songs for the effectiveness of the treatment. Scuse me, gotta pause to wipe a few tears...
IMG_20161126_162729a-2 panels and backdrop.jpg
 

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Discussion Starter #24
Last two panels. These would each hold a layer of the Knauf panel and a layer of the much-thicker UltraTouch batting. A couple of slats were glued into place for support so the UltraTouch did not push the Knauf panel through the front.
IMG_20161127_140935a-supports big view.jpg


Moving quickly now, stapling the fabric into place more simply than before, the upholstery support strip was nice but took forever.
IMG_20161127_140955a-support boards.jpg


Horizontal strips of the batting were cut.
IMG_20161127_150907a-mostly stuffed.jpg


All three pieces in place, they fit just right.
IMG_20161127_150945a-all stuffed.jpg


Backside of a panel the GIK way.
IMG_20161128_104517a-skinny back.jpg


Backside of a panel the OTHER way, with thicker UltraTouch layer added. Not near as pretty. Oh, well. The left-over upholstery strip ended up acting like suspenders, holding the batting in place. And the finger is holding the camera in place - oops!
IMG_20161128_104619a-fat back straps.jpg


Closeups.
IMG_20161128_104556a-straps close up.jpg
IMG_20161128_104549a-close up.jpg


A comparison of the two approaches, rear view.
IMG_20161128_104706a-2 backs.jpg


All in place and ready for another listening test. The slight lean-back gave a very slight improvement in SS&I. There ARE small reflections coming off of the front of those panels. The horizontal and vertical angles are chosen to direct those reflections away from the LP. The result? Nirvana! My phone will be on silent for a few days, don't bother me!
IMG_20161128_110324a-all up.jpg
 

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Is this the front wall, & between the front speakers? Sorry if you states this earlier, don't remember. Can we see a pic that's wide enough to see the speakers in it?
 

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Looking great Wayne! When I made mine I used Roxul (4" total thickness per panel), and used 1"x4" for the frame. I then made a ledge for the rear of the panel so when I pushed the Roxul in it went flush to the rear. I also picked up some cheap cotton material from Jo Annes, and stapled that to the rear of the panels to keep everything nice and sanitary. My panels ended up with the Roxul sticking out the front a bit, but it gave me a rounded/angled corner which works out well in my situation...plus it sits flush against the wall. Now I know some people suggest spacing the panels out from the wall to make them more effective, but I didn't. Have you tried that to see how it effects the sound? I also found that Redwood works better than Pine (IMO) as it is lighter, and safer for first reflection panels hanging over your head. ;) In hindsight I would make all my panels from Redwood (currently only the ceiling ones are redwood), but we learn from our DIY projects.

Are you going to test out to see if the holes on the side of the panels make a difference vs solid sides?
 

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Discussion Starter #27
Is this the front wall, & between the front speakers? Sorry if you states this earlier, don't remember. Can we see a pic that's wide enough to see the speakers in it?
OK, it's a little embarrassing to show that much of the turmoil of the room, but here it is. The speakers are the older MartinLogan ESLs, on the left and right sides of the picture, in what I consider a mid-field configuration, partly driven by the room and partly by personal preference. Dimensions: A=LP-to-speaker-plane=45in; B=center-to-center-of-the-electrostatic-panels=67in; speaker-plane-to-wall=64in; C=LP-to-wall=109in; the width of the front wall being covered by the leaning GIK panekls is about 5.5 ft.
IMG_20161130_171947aWideViewWSpeakers.jpg

And of course a BIG thanks to GIK for the great kits and the great design.
IMG_20161130_172250a-GIK _LOGO.jpg
 

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Discussion Starter #28
Looking great Wayne! When I made mine I used Roxul (4" total thickness per panel), and used 1"x4" for the frame. I then made a ledge for the rear of the panel so when I pushed the Roxul in it went flush to the rear. I also picked up some cheap cotton material from Jo Annes, and stapled that to the rear of the panels to keep everything nice and sanitary. My panels ended up with the Roxul sticking out the front a bit, but it gave me a rounded/angled corner which works out well in my situation...plus it sits flush against the wall. Now I know some people suggest spacing the panels out from the wall to make them more effective, but I didn't. Have you tried that to see how it effects the sound?
Yes, it does make the panel absorption more effective and primarily helps tighten up the bass and sharpen the soundstage. Standing the panels at the angle shown with the small amount of reflection going back to the speaker and not toward the LP makes a BIG difference in the image clarity and the sharpening of the soundstage. In my opinion, it is a major point of the design.

I also found that Redwood works better than Pine (IMO) as it is lighter, and safer for first reflection panels hanging over your head. ;) In hindsight I would make all my panels from Redwood (currently only the ceiling ones are redwood), but we learn from our DIY projects.
Cool idea on the redwood, probably looks sharp too.

Are you going to test out to see if the holes on the side of the panels make a difference vs solid sides?
Nope, bigger fish to fry. I doubt it would make a difference.
 

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Here is a rough diagram of the room layout, with dimensions.

View attachment 132434



I do need to take some REW measurements. I wanted to get a few before adding the batting on the front wall, then forgot. No way am I going to take that down just for a few measurements. I will get what I can.
Funny that you mention that as I was just talking with a friend of mine earlier today, and we both agree that the front wall placement of acoustic panels made a bigger improvement in getting our setups sounding right than the first reflection panels did. In my friends setup he is listening in nearfield vs my 12' MLP.
 

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Wow, very interesting AudioCraver, thank you so much for sharing. It makes me want to get off my behind and do the same thing.

:smile:
 

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Discussion Starter #32
Funny that you mention that as I was just talking with a friend of mine earlier today, and we both agree that the front wall placement of acoustic panels made a bigger improvement in getting our setups sounding right than the first reflection panels did. In my friends setup he is listening in nearfield vs my 12' MLP.
Early reflections are your enemy, unless they are your friend.:laugh2:

If they
  • arrive from the same pan location as the direct wave (left-to-right pan), not significantly outside of or inside of the L & R speaker listening angle
  • arrive at the same delay time within a few microseconds vs the direct wave (example: L & R direct waves arrive at a carefully matched 12 mS and first reflected waves arrive at a carefully matched 10 mS +/- 10 uS or so later)
All will work together to create a killer soundstage, assuming "all else" is in order.
 

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Early reflections are your enemy, unless they are your friend.:laugh2:

If they
  • arrive from the same pan location as the direct wave (left-to-right pan), not significantly outside of or inside of the L & R speaker listening angle
  • arrive at the same delay time within a few microseconds vs the direct wave (example: L & R direct waves arrive at a carefully matched 12 mS and first reflected waves arrive at a carefully matched 10 mS +/- 10 uS or so later)
All will work together to create a killer soundstage, assuming "all else" is in order.
I think what I should have said was that with the first reflection points covered(ceiling and side walls)...the front wall made an even bigger difference when it was covered(we were not expecting as much of a difference as it made). ;)
 

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Discussion Starter #35
I follow you, and can see how you would come to that conclusion. My own work has led to prioritizing the front wall, and still hitting the other early reflection points, but with simple foam square treatments, leading to the same result. I have done nothing with the ceiling and feel no need to, per the reasons given in this previous post (ceiling reflections are "SS&I friendly"). I have been very impressed by the improvement the GIK panels have given, along with the batting behind them on the wall. More on that later...

Edit: SS&I were already good, so one can easily wonder how much an improvement will be gained by treatments like were recently added. Then you try them, and ZOWIE! I am SO glad I did it!
 
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