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post #2521 of 3153 Old 10-16-2018, 01:19 PM
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Q: What's the best way to become a millionaire through woodworking?
A: Start as a billionaire.
LOL Yes indeed.


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It was at this point I realized I can only really work on one box at a time due to the limited number of clamps I had...and even if I borrowed all the clamps I could.
It is a woodworking law that no matter how many clamps you have - it isn't enough. Those JET Parallel clamps are very nice. I prefer them to the Bessey version and have quite a few myself - but for quantity nothing beats the good old pipe clamp. My method for accumulating clamps is to buy one every time I visit Home Depot, Lowe's,Woodcraft, or Harbor Freight (careful which ones here). In this way I've gathered around 70 clamps over the years of varying types and spread that cost out a bit.

Roll Tide.
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post #2522 of 3153 Old 10-16-2018, 01:29 PM
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Originally Posted by p3bham View Post
LOL Yes indeed.




It is a woodworking law that no matter how many clamps you have - it isn't enough. Those JET Parallel clamps are very nice. I prefer them to the Bessey version and have quite a few myself - but for quantity nothing beats the good old pipe clamp. My method for accumulating clamps is to buy one every time I visit Home Depot, Lowe's,Woodcraft, or Harbor Freight (careful which ones here). In this way I've gathered around 70 clamps over the years of varying types and spread that cost out a bit.
Or just use screws?

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post #2523 of 3153 Old 10-16-2018, 01:49 PM
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Originally Posted by DougUSMC View Post
Q: What's the best way to become a millionaire through woodworking?
A: Start as a billionaire.

Same could be said for many hobbies, home theater being near the top of the list !!
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post #2524 of 3153 Old 10-16-2018, 02:33 PM - Thread Starter
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Originally Posted by p3bham View Post
It is a woodworking law that no matter how many clamps you have - it isn't enough. Those JET Parallel clamps are very nice. I prefer them to the Bessey version and have quite a few myself - but for quantity nothing beats the good old pipe clamp. My method for accumulating clamps is to buy one every time I visit Home Depot, Lowe's,Woodcraft, or Harbor Freight (careful which ones here). In this way I've gathered around 70 clamps over the years of varying types and spread that cost out a bit.
Embarrassingly, I own two clamps. As in one, two. Even worse is I've had the same two 12" quick grip clamps for the last 20 years and have never bothered to buy anything more as I'm not full-on into woodworking yet. For the very few times I need them, I call up my list of friends and borrow all I can and then return them cleaner than when they were given to me along with a small 'thank you' gift for the effort. If I get to the point of having a shop, I think I will employ your method to build my own personal inventory.

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Originally Posted by beastaudio View Post
Or just use screws?
I glued using Titebond III and then clamped the living bejesus out to the thing from all possible directions...AND THEN I added the 2.5" exterior grade course wood screws at a 4" spread for that little extra 'umph'. Nothing has moved even a little bit.

Before building and attaching the front baffles I'm going to go through the box and add PL Premium as a 'caulking' at all inside corner locations, including the matrix bracing. Worth the $4 in glue for that little extra bit of peace-of-mind.

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This is going to be epic!!!
Thanks brotha! Just trying to catch up to your awesomeness!!!
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post #2525 of 3153 Old 10-16-2018, 02:46 PM
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Originally Posted by p3bham View Post
My method for accumulating clamps is to buy one every time I visit Home Depot, Lowe's,Woodcraft, or Harbor Freight (careful which ones here). In this way I've gathered around 70 clamps over the years of varying types and spread that cost out a bit.
LOL, that's exactly how I did it, though I bought all my Bessys before there were any Jets, and I'm stuck with them.
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post #2526 of 3153 Old 10-17-2018, 03:57 AM
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So we’ve been planning to clear out accumulated nothingness against the rear wall in our garage. Plan is to build shelves high-up to place said accumulated nothingness.

I’ve been toying with the notion of putting a small woodworking suite of tables and tools against the full length of the rear garage wall once its cleared out......

But I now see that I should avoid getting into such a hobby, as it can be as bad as this HT hobby.

Crisis possibly averted. (Whew!)

Tim—your sub cabinets look like they might cause your house to settle another inch or two just from pure weight. This is the type of build that, once complete, I’d buy a plane ticket just to sit in so I could tell my grandkids I sat in it. The attention to detail is just so pronounced—epicness can be the only outcome.

Keep on wowing us, my friend.


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post #2527 of 3153 Old 10-17-2018, 04:06 AM - Thread Starter
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Rinse and repeat....

Same process for the second box. Not a whole lot of interesting pics, but here it is....







These are the last of the legacy pics from April. I'm sad to say nothing else got done on these sub boxes over the summer so we are essentially up to date with this box build and any new pics will be current progress. My woodworking neighbor was able to borrow a bunch more clamps from one of this buddies for me to use while laminating the two baffle pieces together and then attach the fronts to the boxes.

Just for fun I checked the fit of the first baffle layer in one of the boxes. Immediately started to look real!
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post #2528 of 3153 Old 10-17-2018, 04:37 AM
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Quote:
Originally Posted by BrolicBeast View Post
I’ve been toying with the notion of putting a small woodworking suite of tables and tools against the full length of the rear garage wall once its cleared out......
IT'S A TRAP!!

There are NO "small woodworking suite[s]", there are only "still in progress large woodworking suite[s]".

Do as Tim did, and borrow tools. He is wise beyond his years. Learn from our mistakes. Hand tools lead to power tools. Power tools lead to bench tools. Bench tools lead to "commercial grade free standing tools". Beware the Dark Side...
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post #2529 of 3153 Old 10-17-2018, 05:14 AM
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Quote:
Originally Posted by DougUSMC View Post
IT'S A TRAP!!



There are NO "small woodworking suite[s]", there are only "still in progress large woodworking suite[s]".



Do as Tim did, and borrow tools. He is wise beyond his years. Learn from our mistakes. Hand tools lead to power tools. Power tools lead to bench tools. Bench tools lead to "commercial grade free standing tools". Beware the Dark Side...


Lol ( I actually laughed out loud!). Thanks for the warning...I will definitely avoid this Gargantua of a black hole!


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post #2530 of 3153 Old 10-17-2018, 05:47 AM
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Quote:
Originally Posted by DougUSMC View Post
IT'S A TRAP!!

Hand tools lead to power tools. Power tools lead to bench tools. Bench tools lead to "commercial grade free standing tools". Beware the Dark Side...
Hilarious!! One of the funniest things I have read in a long time ... and true of every "hobby" I am aware of: audio; photography; fishing; drones; golf; ........
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post #2531 of 3153 Old 10-17-2018, 11:40 AM
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Originally Posted by DougUSMC View Post
Q: What's the best way to become a millionaire through woodworking?
A: Start as a billionaire.

I think it's the only way!

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post #2532 of 3153 Old 10-17-2018, 12:53 PM
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Originally Posted by TMcG View Post

I glued using Titebond III and then clamped the living bejesus out to the thing from all possible directions...AND THEN I added the 2.5" exterior grade course wood screws at a 4" spread for that little extra 'umph'. Nothing has moved even a little bit.

Before building and attaching the front baffles I'm going to go through the box and add PL Premium as a 'caulking' at all inside corner locations, including the matrix bracing. Worth the $4 in glue for that little extra bit of peace-of-mind.
I feel like I must have posted my exact process of sealing up a box somewhere at some point and you wrote it down, forgetting it was my own process, as this couldn't be more spot on as to how I've built every box I've ever done...

Until I got a brad nailer which I use now in lieu of screws.

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post #2533 of 3153 Old 10-17-2018, 01:32 PM - Thread Starter
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Front baffles

My neighbor just dropped off all the other clamps he was able to borrow from his friend so it looks like I will be gluing up at least one of the front baffles tonight. A few pics as I mocked up the front baffles on both sub boxes before getting a precise alignment and measurements for all the future screws and mounting locations....










As I said in a previous post, any progress on these boxes from this point forward is real-time and not archived photos from past months of tinkering.
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post #2534 of 3153 Old 10-17-2018, 01:45 PM - Thread Starter
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Quote:
Originally Posted by beastaudio View Post
I feel like I must have posted my exact process of sealing up a box somewhere at some point and you wrote it down, forgetting it was my own process, as this couldn't be more spot on as to how I've built every box I've ever done...

Until I got a brad nailer which I use now in lieu of screws.
The advice was from @Mfusick and backed by a few other DIY sub box best practices which I stumbled across over the years. Maybe your advice was part of one of those posts, but I'm not sure.

Due to the 1.5" thickness of this MDF and 3" thickness on the front baffle, I've had to take different approaches to fixate each and every piece. Brad nails would be too short to get enough purchase in the joining piece of wood. But I totally agree with you regarding the brad nail approach for all the other sub boxes which use standard 3/4" thick MDF. This is the approach I took with the side/surround speaker back boxes in my main theater room.
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post #2535 of 3153 Old 10-17-2018, 04:39 PM
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I can’t believe it’s been nearly two years since Mike got kicked off. He had some crazy ideas, I miss his enthusiasm. Although pages do take a lot less time to load now
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post #2536 of 3153 Old 10-18-2018, 05:58 AM
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Quote:
Originally Posted by TMcG View Post
The advice was from @Mfusick and backed by a few other DIY sub box best practices which I stumbled across over the years. Maybe your advice was part of one of those posts, but I'm not sure.
Wait! At 1 metric butt-ton each, can't you just use the weight of one box lying on another as better than clamps??

You could just lay down the box "to be double baffled", glue, spread, place second baffle on, wipe off excess glue, then lay SECOND box on first box. Epic!

Methinks that would be the best "I've glued the baffle and put this bunch of rando weights/junk on it, to hold it in place while it dries" pic ever!!
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post #2537 of 3153 Old 10-18-2018, 08:01 AM
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Quote:
Originally Posted by beastaudio
I feel like I must have posted my exact process of sealing up a box somewhere at some point and you wrote it down, forgetting it was my own process, as this couldn't be more spot on as to how I've built every box I've ever done...

Until I got a brad nailer which I use now in lieu of screws.





Quote:
Originally Posted by TMcG View Post
The advice was from @Mfusick and backed by a few other DIY sub box best practices which I stumbled across over the years. Maybe your advice was part of one of those posts, but I'm not sure.

Due to the 1.5" thickness of this MDF and 3" thickness on the front baffle, I've had to take different approaches to fixate each and every piece. Brad nails would be too short to get enough purchase in the joining piece of wood. But I totally agree with you regarding the brad nail approach for all the other sub boxes which use standard 3/4" thick MDF. This is the approach I took with the side/surround speaker back boxes in my main theater room.



I think this is just standard best practice.


Brads are great for holding until they don't hold at all. If you are gluing parts together, brads are great for quickly holding a piece in place until the glue sets. There is usually some glue on the shaft of the brad that is activated by the friction heat while going in. This bond is easily broken if there is sufficient stress placed on the joint. I suspect there may be some stress involved in keeping these subs together.



First the holding power of a screw head can't be compared to that of a brad head. Secondly, the threads of a screw have the advantage of a mechanical bond. If you have ever tried to pull a 3 1/2" smooth-shanked spike out of a piece of lumber and then an Ardox (twist) 3 1/2 spike, you'll understand what the thread is doing. Add a hot dipped galvanized coating to the spike and you've got something that will keep a roof on.



Best practice when using screws is to pre-drill with a tapered drill bit; a number 8 tapered drill bit for a number 8 screw, etc. and they come with a integral counter sink for the screw head. The counter sink is usually a convenient 3/8" or 1/2" diameter so that you can go 1/4" deep and hide the screw hole with a 3/8" or 1/2" wooden plug. Any screw, or nail, will act as a wedge when driven into a piece of wood or Plywood edge or MDF or OSB. The drill bit should be the diameter of the core of the screw (hence the taper) to relieve most of this stress and the threads should cut into the wood, giving much improved holding power. A few brads will help to hold things stable until you can get the screws in.


OK, these subs are just scary! Great job Tim!!!


BTW I sent the joke about the best way to become a millionaire through cabinet making to my cabinet maker. He laughed...
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post #2538 of 3153 Old 10-18-2018, 08:24 AM
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Quote:
Front baffles
My neighbor just dropped off all the other clamps he was able to borrow from his friend so it looks like I will be gluing up at least one of the front baffles tonight. A few pics as I mocked up the front baffles on both sub boxes before getting a precise alignment and measurements for all the future screws and mounting locations....
Epic. That 1.5" MDF is awesome and having it doubled for the front baffles is going to make for a box built like a tank. The fact that these are CNC cut on top of it just takes it to a whole other level - you combine that level of precision with massive materials and yeah...

Quote:
IT'S A TRAP!!

There are NO "small woodworking suite[s]", there are only "still in progress large woodworking suite[s]".

Do as Tim did, and borrow tools. He is wise beyond his years. Learn from our mistakes. Hand tools lead to power tools. Power tools lead to bench tools. Bench tools lead to "commercial grade free standing tools". Beware the Dark Side...
LOL yes sir. Unless you're prepared to go all out, stick with a circular saw and a couple random tools. The one addendum I'd make is that Hand tools lead to power tools, power tools to bench tools, bench tools to commercial grade free standing tools, AND commercial grade free standing tools to ultra high quality hand tools whereupon the cycle of upgraditis begins anew.

Roll Tide.
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post #2539 of 3153 Old 10-18-2018, 08:59 AM
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I use confrimat screws when working with MDF and particle board. These plus glue = never coming apart again.

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post #2540 of 3153 Old 10-21-2018, 12:53 PM - Thread Starter
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Quick update...pics later....
  • Front baffles for both 24" subs are finished
  • All inside corners of both BHS-24 boxes have been fully coated with PL Premium
  • Both custom UXL-18 boxes for the rear subs are finished, including separate glue-ups for the front baffles
  • The first of two DIY Soundgroup 4 cu. ft. boxes is glued up and drying right now.

Question...
What should I line these boxes with? I have two rolls of this polyfill insulation-like stuff:


*OR*

I could use 1" Linacoustic. @beastaudio @LTD02 @baniels @popalock

Naturally, I will fill the remainder of the box with polyfill, but how many pounds per cubic foot of volume? I heard 1 pound per cubic foot as a rule of thumb, but should I simply fill the box until full, provided the polyfill is comfortably fluffed out?

Apologies for the idiot questions, but I've never built any sub boxes before.
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post #2541 of 3153 Old 10-21-2018, 12:57 PM - Thread Starter
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Glue porn

OK, one quick pic to tide you over until I can put together the full posts....glue-up of one of the front baffle pieces for the 24" sub box.

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post #2542 of 3153 Old 10-21-2018, 01:07 PM
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The Stonewater Cinema Build Thread

Quote:
Originally Posted by TMcG View Post
Quick update...pics later....
  • Front baffles for both 24" subs are finished
  • All inside corners of both BHS-24 boxes have been fully coated with PL Premium
  • Both custom UXL-18 boxes for the rear subs are finished, including separate glue-ups for the front baffles
  • The first of two DIY Soundgroup 4 cu. ft. boxes is glued up and drying right now.



Question...

What should I line these boxes with? I have two rolls of this polyfill insulation-like stuff:





*OR*



I could use 1" Linacoustic. @beastaudio @LTD02 @baniels @popalock



Naturally, I will fill the remainder of the box with polyfill, but how many pounds per cubic foot of volume? I heard 1 pound per cubic foot as a rule of thumb, but should I simply fill the box until full, provided the polyfill is comfortably fluffed out?



Apologies for the idiot questions, but I've never built any sub boxes before.


I’d ask the designer of the boxes. It’s less important for sealed subs but the volume of the box is fairly important, and filling is generally used to change the damping/air suspension and apparent size of the box (i.e make a small sealed box act like a larger box). Since the filler will change the behavior of the box I’d just check with the box designer on what they intended.
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post #2543 of 3153 Old 10-22-2018, 04:51 AM
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Quote:
Originally Posted by sor View Post
I’d ask the designer of the boxes. It’s less important for sealed subs but the volume of the box is fairly important, and filling is generally used to change the damping/air suspension and apparent size of the box (i.e make a small sealed box act like a larger box). Since the filler will change the behavior of the box I’d just check with the box designer on what they intended.
Since you have all the pertinent design details (enclosure type, enclosure volume, TS parameters for the driver - yes?), I think you can find modeling tools on the web for this.
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post #2544 of 3153 Old 10-22-2018, 06:32 AM
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OK, one quick pic to tide you over until I can put together the full posts....glue-up of one of the front baffle pieces for the 24" sub box.

A very nearly excessive - and therefore proper - amount of glue...

If you had more than the two to assemble this is where one of those jigs we all enjoy so much would come in handy to keep the pieces from sliding around while you clamp. A simple waxed or packing tape covered piece of spare plywood/mdf with a right angle in one corner the length and width of the baffle (also covered with tape) would make it child's play to keep them in line. But with two to do probably not worth the extra time.
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post #2545 of 3153 Old 10-22-2018, 07:43 AM
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RE: polyfill

As stout as these boxes are, polyfill for them is going to be a very simple step in completion. The results from stuffing a box is you will lose a shade of efficiency to ensure there are no resonant peaks inside the enclosure. lining the walls with linacoustic works fine and gives you peace of mind that no "Fluffy" will get into your driver or VC somehow. Another really good alternative is the denim insulation that contains no fiberglass (Win). Dgage uses this almost exclusively for his mariana subs and it's really good stuff.

With that said, I've had loose fill poly in my dual opposed subs now for close to 6-7 years now and never had an issue. People even use whole pillows from wally world with good success. If you use the loose stuff, perhaps some netting around the where the driver comes into the box would give you peace of mind. With the bracing on these bad boys, I'd line the walls with something, maybe spray the braces with sound deadening spray and call it a day.

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post #2546 of 3153 Old 10-22-2018, 08:13 AM - Thread Starter
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Originally Posted by beastaudio View Post
RE: polyfill

As stout as these boxes are, polyfill for them is going to be a very simple step in completion. The results from stuffing a box is you will lose a shade of efficiency to ensure there are no resonant peaks inside the enclosure. lining the walls with linacoustic works fine and gives you peace of mind that no "Fluffy" will get into your driver or VC somehow. Another really good alternative is the denim insulation that contains no fiberglass (Win). Dgage uses this almost exclusively for his mariana subs and it's really good stuff.

With that said, I've had loose fill poly in my dual opposed subs now for close to 6-7 years now and never had an issue. People even use whole pillows from wally world with good success. If you use the loose stuff, perhaps some netting around the where the driver comes into the box would give you peace of mind. With the bracing on these bad boys, I'd line the walls with something, maybe spray the braces with sound deadening spray and call it a day.
@dgage - see THIS post. I would greatly appreciate your insight.

Full disclosure - I already own rolls of 1" polyfill which can line these boxes. I also own a roll of 1" Linacoustic, though I'd rather not use it if there are *not* any real differences between using either of these two materials as box liners as I have just enough Linacoustic for two layers on my baffle wall. I am trying not to have to buy extra Linacoustic by using the material on these sub boxes. And also full disclosure - I have more than a few garbage bags pull of polyfill, ready to go, so it's probably difficult for me to pull the trigger on the denim insulation unless there is a real-life performance improvement.

I also plan to use some netting to protect the driver from loose poly fibers. Question - can this protection be the actual pillow casing itself (i.e. I slice open the pillow, use the contents as stuffing and reuse the actual cloth itself), tacked into position? Or should it be something more open like a very loose Nylon screen material which has much higher air permeability??

Finally - do I really need to damp the bracing?? I've never seen that before. I've only ever seen the box lined, filled with polyfill, netting to protect the driver and that's it. Is there a link to a best practice on this? Any measured performance difference or is this one of those "just in case" type of deals, knowing the box will be sealed tightly?
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post #2547 of 3153 Old 10-22-2018, 08:28 AM
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Originally Posted by TMcG View Post
@dgage - see THIS post. I would greatly appreciate your insight.

Full disclosure - I already own rolls of 1" polyfill which can line these boxes. I also own a roll of 1" Linacoustic, though I'd rather not use it if there are *not* any real differences between using either of these two materials as box liners as I have just enough Linacoustic for two layers on my baffle wall. I am trying not to have to buy extra Linacoustic by using the material on these sub boxes. And also full disclosure - I have more than a few garbage bags pull of polyfill, ready to go, so it's probably difficult for me to pull the trigger on the denim insulation unless there is a real-life performance improvement.

I also plan to use some netting to protect the driver from loose poly fibers. Question - can this protection be the actual pillow casing itself (i.e. I slice open the pillow, use the contents as stuffing and reuse the actual cloth itself), tacked into position? Or should it be something more open like a very loose Nylon screen material which has much higher air permeability??

Finally - do I really need to damp the bracing?? I've never seen that before. I've only ever seen the box lined, filled with polyfill, netting to protect the driver and that's it. Is there a link to a best practice on this? Any measured performance difference or is this one of those "just in case" type of deals, knowing the box will be sealed tightly?
You don't really need to damp the bracing, especially with how yours are done and for a sub box. I did this for my old mains build as a "Just in case" scenario.

As far as the netting and/or the pillow casing, either is fine. Heck some folks don't even cut the pillow open, they just stuff the pillows straight in there no question. The result will be so close to the same that measurability might not even come into play, audibility? Not a chance. Use what you've got. I'm confident David will tell you the same thing.
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post #2548 of 3153 Old 10-23-2018, 04:20 AM
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I used the netting stuff to hold the polyfill in place when built my 4 DIY subs. Works like a champ.
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post #2549 of 3153 Old 10-23-2018, 05:47 AM - Thread Starter
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I used the netting stuff to hold the polyfill in place when built my 4 DIY subs. Works like a champ.
Thanks! Do you have a link for the netting product you used?

I did a bunch of research last night and the consensus is wool / cotton is best for making the box seem bigger to the driver than it actual is. Polyfill is a close second and would only amount to 0.5db - 1db difference in the final specification, if at all. Main takeaway: stuff it with what ya got, just make sure it's adequately stuffed to reduce / eliminate the internal box harmonics from the backwave.

If I were to line the box, Linacoustic is preferred only because of the facing which makes it easier to adhere and keeps its fibers bound together. No real acoustic difference between Linacoustic and Polyfill when lining a subwoofer box as in this application. Since I have the rolled poly batting and want to save my Linacoustic for the baffle wall, I'm going to line the boxes with the rolled batting then stuff the rest with polyfill with a 'medium-ish' pack. Recommendations I've read in sub forums is closer to 2 pounds per cubic foot of volume vs. the standard 1 pound per cubic foot which is good but not optimal.

So there you have it - lining the boxes with poly batting then filling to whatever level is comfortable between 1-2 lbs. per cubic foot, then tacking the netting to the matrix bracing to keep all the loose poly fibers out of the driver itself. As I plan to use Super77 spray adhesive to attach the batting to the box, the other cautionary word of advice from the subwoofer forums is to let the box "air out" a minimum of 24 hours before attaching the front baffle as the VOCs which off-gas from the curing adhesive can affect the driver and any other adhesives used to bond the actual driver together.

By way of update, I finished all four of my DIY Soundgroup 4 cubic foot boxes and only have to attach the front baffles box-by-box due to limited number of clamps I was able to borrow. The finish work for all these boxes will come later. I simply wanted to get ALL the boxes built so all the parts / pieces / loose sub drivers / supplies / etc. were used up and out of my way....plus I could confidently return all the clamps, leaving me a relatively empty work space.
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post #2550 of 3153 Old 10-23-2018, 11:04 AM - Thread Starter
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Proof of progress...

I had a few minutes after lunch here in my home office so I went down to the basement to take some photos.

3 of the 4 DIY Soundgroup 4ft^3 sub boxes complete...


...and the fourth just unclamped and now waiting for its baffle installation.


Just for kicks I took one of the two custom rear sub boxes and threw it into the recessed back box I created. Now as dumb as this sounds, I quite literally cut a piece of scrap 2x4 to the exact width of the subwoofer plus 1/2 (leaving 1/4" gap on either side when installed) to make sure my inside back box dimensions were consistent. I'm not sure how it ended up like this, but the sub was more like an exact fit with barely 1/8" to spare. You could feel the 'cush' of air rushing out of the back box as I slid the sub into place.

Here you can see the incredibly slim gap along the vertical edge....


For the height, I left just enough room for the subwoofer to have the beefy rubber feet and accommodate a right angle Speakon connector. Here you can see the remaining gap above the rubber foot is just barely enough to accommodate the connector when the sub is shoved into position.


And finally, a pic of the installed sub box, just for fun.


Rear acoustic treatments will be 4" deep, so this low-profile installation will allow 2" acoustic treatments on the surface of the subwoofer where-needed and allow about a 2.5" gap between the subwoofer surround and the back side of the acoustic fabric to allow for XMAX without the driver 'thwapping' against the fabric when everything is operational.

Next up is lining and filling the boxes, plus preparing for final front baffle glue-up and installation on these rear subs and the two 24" subs.
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