Saga of the "Old Vic" - Page 12 - AVS Forum | Home Theater Discussions And Reviews
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Old 03-02-2010, 03:55 PM - Thread Starter
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I made a bit of progress on the acoustic treatment. The bulk of the side wall furring blocks and treatment (1" bonded acoustical cotton) is up. I believe this stuff is made from recycled jeans. The thought that I was touching something once worn by Angelina Jolie kept me going The stuff is a little awkward to cut all the cutouts for the furring strips although the 1" thick panels were just about manageable with my wife's largest scissors.

The remaining drywall areas in the upper portion of the room are going to house some DIY QRD diffusers of varying depths (1", 2" and 4"). I have a materials list for those so expect some dust to fly next week.

I need to figure out how I'm going to finish the entrance to the closet before I can complete the walls in there. I'm thinking of framing an archway and lowering the (fabric) ceiling by 1' -- it feels too high in there right now. [I realize that comment will piss off a few folks. I know I'm really lucky to have 10' ceilings]



I also added a bit of cotton to the back of the speaker recesses to help remove any "boxy" sound impairment. If I stick my head in there now and shout it sounds very different than it did before treatment. In fact the whole front of the room sounds so different now. Is was planning to take another REW measurement at this stage but I think I'll continue to make progress rather than get stalled setting all that up again.





I didn't show this before but I used "Sillites" for the light trays (4 of them in total). I also followed other builders here and made my own power bridge from the Leviton part and a metal blank cover.



Enough coughing and wheezing for one day. I'm now at the computer spending some more money ordering materials..

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Old 03-02-2010, 05:49 PM
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Damn it Man!!.. Your work always looks so perfect!! I need a different camera!

I'm really, really interested in your plan for the QRD build's.

You definately have the saw for ripping the various wells to any size you want.. I was just planning on kinda stacking 3/4" strip cut to width to get the heights, with 1/4" ply in between.

Brad

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Old 03-02-2010, 06:01 PM
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You're only running 1" on the sides? I was always told that you should have at least 4" of absorption to get a full spectrum. If it was only 1 to 2" it would only absorb a fraction of the frequencies i needed. Is this incorrect as I'm sure you have done some research into this?

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Old 03-02-2010, 07:34 PM - Thread Starter
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Originally Posted by KNKKNK View Post

Damn it Man!!.. Your work always looks so perfect!! I need a different camera!

I'm really, really interested in your plan for the QRD build's.

You definately have the saw for ripping the various wells to any size you want.. I was just planning on kinda stacking 3/4" strip cut to width to get the heights, with 1/4" ply in between.

Brad

You found my secret -- a camera with rose colored lens

The QRD build should start soon but I'm planning on 1/8" ply for backing and for the fins (I understand the thinner the better -- I could even use some scrap laminate..). The wells are 1" width. I have two ideas for the wells: Either I go solid and spend a day ripping and planing to the various heights and create a sandwich glued to the 1/8" back or I could make it hollow fitting the 1/8" fins into slotted top and bottom forms, use temporary height shims to hold 1/4" (ply or hardboard) in each well. I would tack glue the 1/4" into each well (just enough so the whole thing doesn't fall apart when turned over and finally fill the back side with expanding foam. Once dry it would be pretty easy to cut off the excess foam, sand flat and optionally fit a 1/8" backing sheet. I like the idea of the hollow approach to keep weight down. I just need to run and experiment to see if its practical.

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You're only running 1" on the sides? I was always told that you should have at least 4" of absorption to get a full spectrum. If it was only 1 to 2" it would only absorb a fraction of the frequencies i needed. Is this incorrect as I'm sure you have done some research into this?

4" would almost certainly be too much (well, I guess it would be ok if you didn't cover too much of the wall). Anyway, bpape did the layout for me so I trust his plan. Most of the walls will have 2" of space behind the fabric (primarily to cover the depth of the planned QRD diffusers) so I could fit an extra inch but Bryan said not to do that. My room is only 15' wide so I don't want to narrow it more than I have too. Then will be 4" of absorption at the rear of the room.

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Old 03-02-2010, 07:56 PM
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I agree with Brad, your work looks like it should be in a DIY Theater book or something. And you work so fast! And yes, I am jealous that you have 10' ceilings.

Keep up the good work!
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Old 03-02-2010, 07:59 PM
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Your attention to detail is just amazing Moggie. I thought my OCD was up there, but you, my friend, take the cake!

Mike
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Old 03-06-2010, 07:03 AM
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Quote:
Originally Posted by Moggie View Post

You found my secret -- a camera with rose colored lens

The QRD build should start soon but I'm planning on 1/8" ply for backing and for the fins (I understand the thinner the better -- I could even use some scrap laminate..). The wells are 1" width. I have two ideas for the wells: Either I go solid and spend a day ripping and planing to the various heights and create a sandwich glued to the 1/8" back or I could make it hollow fitting the 1/8" fins into slotted top and bottom forms, use temporary height shims to hold 1/4" (ply or hardboard) in each well. I would tack glue the 1/4" into each well (just enough so the whole thing doesn't fall apart when turned over and finally fill the back side with expanding foam. Once dry it would be pretty easy to cut off the excess foam, sand flat and optionally fit a 1/8" backing sheet. I like the idea of the hollow approach to keep weight down. I just need to run and experiment to see if its practical.

I like the thought process with the use of foam..Since I read that I have been trying to think of a material that could be poured into the wells in measure volumes, that would harden to create the appropiate depth eliminating the shimming process.. some form of epoxy came to mind but weight and probably cost would be an issue... still an interesting approach..

I dont know why I typed 1/4" in my post for my fin thickness, i've always planned on using 1/8". Before going any further, Ill make the following disclaimer: I am only tyring to learn about diffusion and have no actual knowledge or experience!!

Now with that said, I was operating under the assumption that with QRD's the depth of the well impacts how low the frequency goes IE.. a 2" deep well may only diffuse to 2K Hz while a 4" deep well gets you into the ~900Hz range, and that the width effects the high end. IE.. a .75" wide well could diffuse into the 9K range while a 1" wide well only hit to ~ 7K. So a .75 deep well, 4" wide would diffuse frequecies in the range from ~900Hz to 9Khz. which would seem to me that building with 3/4" Vs 1" wide wells would provide a wider range of diffusion.

Either way the diffusers look quite time consuming to build and because I live in a perpetual state of Laziness, I am always looking at a way to simplify things..

I realize this is off point for the discussion of the QRD's but one concept I have pondered, is what I have come to think of as a cross between a skyline and a qrd built from a simple stack up of wedges and fins with alternating offsets.

The fins between the wedges were eliminated from my concept sketch for clarity.



My thinking, or lack there of, was that the average volume of the wells at any given depth would be similar to that of the QRD's. Unfortunately I lack the wherewithall to validate or invalidate my concept both on paper and in real life.

It would be interesting to hear what any of the accoustic pros thought the result would be. although experience tells me if it would work, someone else would have thought of it

From the amount of space open on your walls I can see a signifigant amount of QRD building in your future.. and I have faith that you will develop a build method that can eaisly be deployed (read copied) by us less ambitious fellows.


Brad

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Old 03-06-2010, 09:31 AM - Thread Starter
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Brad, as always some good lateral thinking here. Your last point first: I believe there are many ways to design diffusion panels it just appears to be an exercise in mathematics to figure out! I saw this book in a bookstore recently "Acoustic Absorbers and Diffusers: Theory, Design and Application By Trevor Cox, Trevor J. Cox, Peter D'Antonio" and I'm pretty sure I recall a section on pyramid and triangle diffuser design... Although, as an engineer and was once reasonably good at maths, that skill is very rusty so I think I'm going to stick with the tried and tested design of a 2D QRD panel. Building a DIY HT is even more work than I imagined when I started!

As far as construction of the QRD diffusers you did give me an idea for a third method. A few years back I helped a neighbor build a 2 seater airplane using a foam and glass fiber technique. The blue foam was cut with a hot wire (just a bigger version of that used to cut the fiber in my star ceiling) and was available in many different sheet thicknesses. So another lightweight method would be to make the raw panel without inserts in the wells, then fill the wells with slightly undersized pieces of blue foam and then finally fill each well up to the desired height with epoxy resin. This would minimize the amount of resin (and thus weight and cost) and create a hard surface at the bottom of the well...

I do have quite a number of panel to build so I need to come up with some kind of efficient production process. I do have a very accurate fence on my table saw and so cutting wood to size wouldn't be to hard so I'm wondering if all the "foam" ideas may actually be more work in the scheme of things.

You make a good point about 3/4" wells vs. 1" though. If I decide on the solid wood approach I'll ask bpape if this is ok. The main reason for me (frequency range aside) would be the availability of exact 3/4" sheets which could then be ripped to the correct depths in large 8' sections thus saving time -- I cannot find anything 1" thick locally.

I have a few more days of finish up work and then onto the QRD panels..

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Old 03-14-2010, 02:29 PM
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Hey Moggie,

Just one more quick post to show you the completed star ceiling

I still have to mount my light sources and clean up the bundle of fibres, but the hard work is done and i'm very happy with the result

It's alive!!

Cheers,
Simon
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Old 03-14-2010, 03:04 PM
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Hi Jeff, this is an automatic reply

I'm currently on vacation until Feb 2nd pursuing my flying hobby.



Theater progress will resume when I get back... taken some initial room measurements and I'm in the middle of acoustic treatment on the walls.

Thanks for checking in.

Cheers.

I am still amazed with your attention to detail. Hey, you wouldnt live in NW indiana would you? I have seen a similar contraption flying around this area from time to time, although I havent seen it for awhile.

Keep up the good work.
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Old 03-14-2010, 03:45 PM
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I am still amazed with your attention to detail. Hey, you wouldnt live in NW indiana would you? I have seen a similar contraption flying around this area from time to time, although I havent seen it for awhile.

Keep up the good work.

I do but your not gonna see me up in the air. Well NE

Adam

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Old 03-14-2010, 06:13 PM - Thread Starter
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Hey Moggie,

Just one more quick post to show you the completed star ceiling

I still have to mount my light sources and clean up the bundle of fibres, but the hard work is done and i'm very happy with the result

It's alive!!

Cheers,
Simon

Simon, awesome job! Now we have a matching northern and southern sky! Hey, have you started a build thread? If not, you should because it looks like you have a really nice build there.


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I am still amazed with your attention to detail. Hey, you wouldnt live in NW indiana would you? I have seen a similar contraption flying around this area from time to time, although I havent seen it for awhile.

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I do but your not gonna see me up in the air. Well NE

No California, but most states have a hundred or so flyers. It's not a big sport but it is fun. It's called Paramotoring -- basically it is a paraglider wing with a backpack 2 stroke engine and 48" prop. It is *so* much fun and would you believe that statistically it is the safest form of personal aviation! All you need is 100' of clear space and good weather...

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Old 03-14-2010, 07:53 PM - Thread Starter
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Some progress to report. I continued with the acoustic treatment until I ran out. I'm waiting for the final shipment to finish the back wall.



I framed an archway for the closet entrance. This will all be covered in fabric and hardwood trim so the furring strips are to bring it to the correct depth.



Now that my wiring is complete I was able to fill the remaining soffits. The sides and rear have a 2" oc703 bottom covered with an FSK covering. The idea is to allow them to function as a base trap without killing the high frequencies.



And I finished up a whole bunch of loose ends that aren't very photogenic but include building an ceiling access door that was fitted into the equipment closet (there is just enough room to get up there and it provides access to the point in the theater ceiling where all the wiring enters so I thought it would be a good idea. I also tidied up the wiring and added junction boxes in the columns for the column back lights.

I also started on the mass production of the QRD panels...

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Old 03-14-2010, 07:58 PM - Thread Starter
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I haven't seen many builds using QRD diffusion panels so I thought I'd document my build process in a little more detail. In a nutshell I'm treating the majority of the upper side and rear walls with DIY QRD panels that will be hidden behind the wall fabric. Because the the different treatment depths as well as design reasons I have a total of 25 panels to build! So I needed to create an efficient build process.
The panels consist of 1", 2" and 4" depths. Specifically they are all 2D design in 1" N7, 2" N17, 4" N7 & N11 configurations. The 1" and 2" are all 32" tall and the 4" versions are 38" tall. They will all be mounted with vertical fins. Since all my diffusers have zero depth wells at the ends I decided to make each of the panels symmetric with half a well at each side. Technically when they are mounted I should cut off 1/2" from the extreme left panel and fit to the extreme right. I'm not sure how significant this detail is but I'll probably do it right else my OCD will get the better of me ;-)

For further reading this is an excellent reference: http://www.subwoofer-builder.com/qrd.htm and includes some cool design software called QRDude http://www.subwoofer-builder.com/qrdude.htm

After some thought I decided to build the panels with hollow wells to keep the weight under control and reduce the quantity of material required. The first step was working out the materials list. This was the first eye opener on the magnitude of this undertaking.
For the 25 panels I will need:
251 fins
226 well bottoms
50 sides
50 routed top/bottom plates
25 back panels
... in a myriad of sizes...

After drawing out some cut sheets I needed:
7 sheets of 3'x7' 1/8" MDF (fins)
2 sheets of 4'x8' 1/4" MDF (well bottoms)
1 sheet of 4x8' 1/2" MDF (sides)
1/2 sheet of 4'x8' 3/4" MDF (top/bottom)
2 sheets of 4'x8' 1/8" ply (backing)

To ensure accuracy of the panel and particularly the well depth I started by creating a template for each of the 4 QRD sizes. Step one was to mark up the fin and well positions and figure out the depth of each well.



Then, using scrap wood from around the shop I cut furring strips to the depth of each well and attached to the template.



As I build the panel the front side will be facing the template so a couple of the wells needed special treatment -- no well bottoms in the full depth wells and 1/8" bottoms in a couple of wells that were 1 7/8" depth (could not fit 1/4" stock).

With the template moved out of the way I started cutting. After considerable cutting I cut some more. Then spent hours cutting followed by lunch and more cutting. Then after an 8 hour ordeal I was done.

Seriously, I did give a lot of thought to how I was going to cut 600 panels efficiently and so invested in a few tricks. Firstly I laminated as many layers together as I could with low-tack double sided tape as well as some painters blue tape. This allowed me to cut 7 pieces of the 1/8" stock in one go.



The top and bottom panels have slots to accurately accept the fins and this was made by using a 5/32" blade (not the thin kurf blades that are popular these days) to 1/4" deep on three quarter sheet of MDF. After all the slots were cut I ripped the panels to the three sizes, used a router to channel the ends and then chopped to size on the table saw or chop saw.



The old adage of "measure twice, cut once" is doubly true when you are cutting 7 sheets at a time. Luckily I only made a slight mistake of initially cutting 200 well bottoms 1/2" too long. Better long than short! The solution was to load up the sled on my table saw and cut them down to size ninety at a time!



So, after 8 hours at the table saw, this is the little pile I was able to create.



The moment of truth -- a dry fitting of one of the QRD designs. I was very careful to make accurate cuts, because in a design like this an error will compound. I'm happy to report everything fitted perfectly (the 1/64" undersized well bottoms was a really good idea).



Tomorrow I'll start gluing these up 4 at a time and filling the back side with expanding foam... stay tuned!

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Old 03-14-2010, 08:26 PM
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Just holy wood planks! I just need to check up on your build and I instantly get a feeling that my office build is 'not that bad' for workload. Great work - it's going to be worth it!

Mike
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Old 03-15-2010, 05:17 AM
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Hey Moggie, while your at it can you just go ahead and make me two panels? It wont take you long at all. JK.This is nuts. There is almost no way I would be able to do such accurate work but I am very intrigued by it. I have though about doing something like this a while back. How did you get info to determine exact placement of each piece? When you mentioned that small mistakes compound I was very nervous for you. Keep up the great work and if you get board you can come over to my house and work on my place.

These are hidden right? It would look really cool if you could stain them and have them as a decorative part of the theater.

So let me know when you have those panels done for me ok

Adam

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Old 03-15-2010, 07:48 AM - Thread Starter
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adam, sure I'll build you 10 panels if you like The only part I was worried about was the width of the well bottoms, which if too big, would have created an assembly problem. Luckily I have a really nice fence system on my table saw and can get down to 1/100" accuracy quite easily when I need to. As for placement it is no secret that you want diffusion in the upper rear half of the room but the specific choice of panels particularly the back wall was bpape's design. There are things like minimum seating distance that need to be taken into account.

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Just holy wood planks!

I feel that owning a home theater is already over the top, so why not go over the top in every aspect of the build! The good news is that I counted my fingers after the day of cutting and I still had 10!!

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Old 03-15-2010, 06:30 PM - Thread Starter
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QRD Build (part2)

Day 3 and 12 hours in...
Spent the entire day gluing and getting the first two panels formed.

My plan was to directly assemble the panel on the template but I wasn't sure I could contain the wood glue so as a precaution I sprayed some polyurethane varnish at the business ends of the template and then stuck some scotch tape to act as a release agent. I'm glad I did because you can see the pool of glue in the photo.


I was lucky that this panel did release after the glue was dry but clearly this was not a smart way to assemble the panel. The solution was to glue the frame and fins first and then fit into the template. This ran the risk of getting the frame off square but it turned out that they still had some movement which would allow be to wiggle them into the templates.
First job was to glue and nail the frames and then fill the channels with glue and assemble the fins.



To aid getting everything square and aligned I use some offcuts from the panel ends, then left in the sun to dry.



Around lunch time I had this little stack



A quick trip to HD to pick up some of these:



Then back home to complete the stack:



I managed to get the first two panels fitted to the template and the expanding foam applied before dinner. The wood protrusions are 1" separators in the empty wells to remind me not to spray foam there ('cause it's fun and easy to get carried away) and also to prevent the foam squeezing these wells closed as it expands.



I'll let you know tomorrow how this all turns out.

To be continued...

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Old 03-16-2010, 05:47 AM
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So, after 8 hours at the table saw, this is the little pile I was able to create.



That must'a been one Hell'er pile of sawdust!!!

Very Impressive, Excellent planning and execution for your assembly concept.. if thats what OCD does, i gotta get me some...

Brad
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Old 03-16-2010, 06:01 AM
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Moggie, you sir, are officially nuts! Making your own QRDs? Certainly there was something else more "fun" to work on!

Mike
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Old 03-16-2010, 07:43 AM - Thread Starter
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That must'a been one Hell'er pile of sawdust!!!

You bet it was ... and MDF sawdust is such lovely stuff You know that I'm taking all these pictures for you, right? Trying to persuade you that in actuality making these panels has been a whole lot less work than the star ceiling.

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Moggie, you sir, are officially nuts! Making your own QRDs? Certainly there was something else more "fun" to work on!

Most definitely nuts. I've had the HT building itch for at least 10 years so it's taking quite a scratch to satisfy it. Mind you I'm now really focused on completing this summer -- I'm so far behind on movie watching.

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Old 03-16-2010, 09:57 AM
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Originally Posted by Moggie View Post

You bet it was ... and MDF sawdust is such lovely stuff You know that I'm taking all these pictures for you, right? Trying to persuade you that in actuality making these panels has been a whole lot less work than the star ceiling.

Your pictorial documentation of the QRD's and Star Ceiling is Stellar (ha! pun intented), and greatly appreciated... I'm committed to diffusion (and experienced in Confusion), I think though that since my panels will only be 2" deep, I can get by with 3/4" wide wells.. which should greatly simplify the process by allowing me to cut sheet to width for well depth. Basically building a frame and stacking the fins and wells in the frame... thats the plan as of now.. but I'm currently using alcoholism as an enabler for laziness....

Brad

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Old 03-16-2010, 01:38 PM
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but I'm currently using alcoholism as an enabler for laziness....


Here I thought I was the only one with that laziness issue

If I had it to do all over again, I'd still hit that shot.
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Old 03-17-2010, 10:40 AM - Thread Starter
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Happy St. Patricks Day!

So did the initial QRD panels turn out ok? Well, yes and no...

Here are the first two completed panels. I'll spray paint them when they are mounted on the walls so they cannot be seen behind the fabric walls.



To rest of the process consisted of trimming off the excess foam with a flat blade. I'm using a flexible flush cut saw. Then cleanup with some sandpaper stuck to a plat piece of wood with some spray adhesive. Finally a thin piece of ply was attached to the back of the panel.



Here is one of the larger panel (I feel like a bee keeper)



So was the exercise in creating light weight panels a success? Not really. It was pretty efficient but the problem is that the expanding foam just doesn't know when to stop expanding . I had mistakenly thought that leaving the back open and using a template to hold everything together would have allowed the foam to escape, however it doesn't seem to work that way -- it holds some residual spring that caused the fins to buckle when released from the mold so clearly unless the fins are more robust and perhaps glued together first, expanding foam is not the answer. This is a shame because the one thing it did do was glue all the parts together thus eliminating a lengthy set up process. Perhaps there are better choices of expanding foam but I ended up returning my cans in favor of some rigid foam and a new approach:

With a bit of work I did manage to rescue the first two panels but there is still some slight distortion that bothers me:



New (and final) approach was to purchase a 1" polystyrene sheet and rip to size on the table saw. Now assembly consists of painting epoxy (NOT the polyester "resin" shown in the pic -- that melts polystyrene!) into to the rear of each well and then inserting the foam. This is a little more time consuming but keeps the panels nice and straight. Just 18 more panels to go..


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Old 03-21-2010, 01:21 AM
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Originally Posted by Moggie View Post

.

Hey Moggie,

I was wondering how you were planning on attaching the wood trim along the top, middle and bottom to those blocks you installed? Were you going to just glue them? or use brads?

Cheers,
Simon
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Old 03-21-2010, 09:36 AM - Thread Starter
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Hey Moggie,

I was wondering how you were planning on attaching the wood trim along the top, middle and bottom to those blocks you installed? Were you going to just glue them? or use brads?

Cheers,
Simon

Hi Simon, the blocks are to create the correct stand-off from the walls for mounting the fabric panels and trim and to maximize treatment coverage. On top of the blocks I'm either attaching frames made from some strips of OSB board or some maple laminated MDF (use where this backer will show through as a reveal between panels). Then, when I get round to purchasing them, I'm going to mount fabric-mate panel strips to the frame. The frames are attached with glue and finish nails -- no nail will show so long as I avoid the strip that will be visible as a reveal because the final hardwood trim will be fitted to the frame in between the fabric tracks. I don't know how I'll fit that hardwood but I'll likely use brad nails and fill the tiny holes with filler. Brads are very small and hard to see if fired to the correct depth just below the surface.

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Old 03-21-2010, 08:08 PM
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Thanks Moggie,

Seeing as it's all decorative I figured the odd brad with some filler would be sufficient.

Did you just screw the furring strips directly to the sheets?

Cheers,
Simon
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Old 03-21-2010, 08:38 PM - Thread Starter
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Simon, I lined the entire room with a 1/2" layer of OSB prior to the drywall. This makes it very convenient to screw to just about anywhere. The OSB does not have a huge holding power but coupled with some construction adhesive (liquid nails in the US) it is working fine. Without the OSB I would have used longer furring strips so I could bridge studs and them screwed into these.

Cheers.

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Old 03-22-2010, 09:39 AM
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Originally Posted by Moggie View Post

To rest of the process consisted of trimming off the excess foam with a flat blade. I'm using a flexible flush cut saw. Then cleanup with some sandpaper stuck to a plat piece of wood with some spray adhesive. Finally a thin piece of ply was attached to the back of the panel.


Looks just like a cut of fresh baked cake.

Moggie, your diffuser build is very interesting, I only saw those foam diffusers with wedge shape before. I did some googling and see the mechanism behind the QRD panel. So I have two questions for you, in terms of the effectiveness of the diffuser panel, 1, can you just glue and stack 2 or 3 piece of 2" rigid insulation foam boards and use a router to cut channels in different depth? 2. Looking at the irregular patterns of cured expansive foam in your picture, would it be even better just spay the foam on a piece of board randomly and what ever it comes out it would be the diffuser itself because of the irregularity pattern makes it more effective?
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Old 03-22-2010, 10:46 AM - Thread Starter
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theWalkinater -- thanks for stopping by.

Well, I'm no audio expert although I'm learning tons during this build process but to answer your questions:
1. Certainly there are other ways to create the QRD panels. If you look into the theory you will find that the "fins" are an important part of the design so with their inclusion you have to build the wells separately. The other question I would have is how good a reflector the surface of the raw foam would be. In my case the well bottoms are all 1/4" MDF. That said, I finished up the remainder of the panels using a slightly different technique: I cut the rigid foam to the correct height minus the 1/4" for the well bottom. Then set the foam piece into each well with epoxy. This was slightly more time consuming than the expanding foam so it's a shame that didn't work out as planned. I'm building (built actually) 30 individual panels so I needed to get the process as efficient as possible!
2. Any irregular surface will act as a diffuser it just won't be a QRD one. Mathematically a QRD design is much better and more predictable than random approaches. I'm really happy with the nature of the sound in the rear of my room now -- all the slap echos have gone, but I'll never know how much better the QRD approach was than alternatives. Your "random blobs of spray foam" idea is really interesting and probably something worthy of discussing in the audio area or in the master acoustic treatment thread. In fact if you don't ask, I might on your behalf because you have be thinking...

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