Month: January 2022

When I built my screen, I knew it was going to be big in the room, but I really liked the size and experience. The downside is that my second row of seats is on a 8″ riser and if you use a riser calculator with my seats and dimensions, the riser should be closer to 18″. So I started to research the best way to build my new riser, which of course led me to the AVSForum. As I researched risers, I came across the concept of a BOSS riser. You can read more here, but BOSS stands for Baffle Open Sub Shaker. Essentially, a BOSS riser connects to the sub out on your AVR using an external amp to provide amazing tactile response. This is similar to the concept of a Buttkicker or other amplified seat-shaker that augments your home theater experience. The previously mentioned thread is a wealth of great information, but its 380 pages of reading. So, I thought I would document my experience, hopefully providing some of that information in a single place.

I’ll be constructing my riser in three basic stages: the riser build itself, finish work (trimming, painting, and carpeting), and finally shaking. This blog post will cover the riser built itself. This involves the actual base, the plywood top, and the of course, the subwoofer. I will also cover wiring up the subwoofers even though I won’t be adding the amp and such until later. Let’s start by taking a look at the tools I used. You might be able to get away with less tools, but this is what I used and would recommend.

BOSS Riser Tools Required:

• Miter Saw
• Circular Saw
• 8ft Cutting Guide
• Clamps (for the cutting guide)
• Router
• Hole Cutting Guide for Router
• Extra Straight Cutting Router Bit (for when mine broke)
• Impact Driver
• Power Screwdriver
• Drill
• Tape Measure
• Pencil
• Work Surface
• Soldering Iron
• Small Torch or Heat Gun

BOSS Riser Building Materials

Now that we have our tools lined up, we need something to build the riser out of. The size of the lumber you use will be dependent on your height, width, and depth requirements. I decided to use 2×8’s (7.5″) with a double plywood top (1.5″) resting on isolators (1″, which we’ talk about later) and carpet savers. This should give me about 10″ of additional height for the seats. Here’s the full list of materials I used:

• 2 @ 2×8 (10ft)
• 2 @ 2×8 (8ft)
• 3 @ ¾” 4×8 Plywood (I used sanded pine, 7-layer from Home Depot)
• 24 @ 2″ Platinum Silicone Hemisphere Bumper
• 24 @ Carpet Savers
• 6 @ JBL GX1200
• 100ft @ Speaker Wire
• 6 + 6 @ Quick Splice Connectors
• Various Heat Shrink
• 1lb @ 3” Construction Screws
• 1lb @ 1 ¼” Construction Screws
• 1lb @ 1 ⅝” Drywall Screws

The Design

I’ve mentioned before how much I enjoy SketchUp, so of course I used it extensively for this process. Here’s the top view:

And here’s the bottom view:

I tried to put my supporting structure right under the feet of my home theater seats. So I was less concerned about 16″ centers, and more concerned about it being supportive of the seats. I also had to piece in the plywood since 10ft plywood is obscenely expensive.

Building The Supporting Structure

This was by far the easier part…it’s like framing a house. I cut two boards at 100″ and eight boards at 39″ giving me an overall platform size of 100″ x 42″. This is a pretty big platform, hence the six drivers. I screwed this together with 3″ construction screws:

Isolators

Before we move on to the top, we need to talk about isolators. These are basically rubbery half-circles that isolate the riser from the room. This means that the power from the drivers stays contained in the riser and doesn’t transfer into the room. More shake! The guidance is every 24″, but I couldn’t quite make that work, so I ended up with three per support:

The Top

Now for the fun part…cutting giant holes. First I cut the plywood down using my circular saw and a straight cutting guide. Then I measured for the first hole and tried out my circle cutting guide for my router.

Now that the holes are cut we can dry fit it on the base:

Next I measured and cut the extra ends to for both layers and dry fit those as well:

Now we can finish cutting the top, which has bigger holes (12.5″)…but before I could finish, I broke the bit. I think I let it heat up too much rather than waiting between holes. Luckily I had another bit.

Moving on…I finished the second layer of the top and then attached the first layer to the base with 1 1/4″ construction screws. Then I applied a layer of titebond wood glue and attached the second layer:

It should also be noted that the first layer was screwed on every 4 inches and the second layer was offset so that I didn’t hit the screws below. This made it 100% rock solid. I had my son (who is 6) jump up and down just to see it bounce a little on the isolators…pretty cool.

Wiring The Subs

Once I finished the structure, it was time to wire up the speakers. With six speakers, the recommended configuration is one of series/parallel. Basically two sets of three speakers in series, and then those two sets in parallel. The math leads us to a 6 ohm load which will eventually be attached to an NX3000D in bridged mode. I soldered the negatives together on the last two speakers with connectors:

I did the same thing with a red wire for the positives of the first two speakers. Then I connected each speaker together with the negative of the first to the positive of the second and the negative of the second to the positive of the third. I soldered the connectors to the wires:

BOSS Riser Driver Installation

As this is a BOSS riser, I need lots of subs! Here are a few ready for installation:

Next up I set them on top to attach my connectors and run the wires. I made them a little shorter than intended so I had to wire and install each one rather than wiring them up and installing them all at once.

Conclusion

All in, this portion of the project took me roughly three nights of work. Two longer nights and a third night to finish it off during the week. Next up, we’ll add the Oak trim and get it all painted and carpeted! In the meantime, here is how it looks with my chairs finally high enough:

And here is the aftermath:

I must have gotten too much enjoyment out of my DIY screen since I haven’t made it back to post the follow-up of how I actually built the screen! This process starts with some wall preparation, then we’ll get into the actual frame build, the backing, and then finally the screen material. Let’s get started with some tools that I used and the materials.

DIY Screen Tools Required

• Miter Saw
• Table Saw
• Kreg Jig and Bit
• Staple Gun
• Tape Measure
• Pencil
• Paint Roller/Pan
• Paint Brush
• Ladder

DIY Screen Building Materials

• 4 @ 1×4 (12ft) Poplar Hardwood
• 2 @ 1×4 (8ft) Poplar Hardwood
• 6 @ 1×3 (8ft) Poplar Hardwood
• 1 @ 1×6 (8ft) Poplar Hardwood
• 13ft @ Seymour AV UF Screen Material
• 1 @ Silver Ticket Black Backing for Acoustically Transparent Screens
• 1 Box @ Kreg Hardwood Screws
• 1 Box @ 3/8 Staples
• 1lb @ 2″ Construction Screws
• 4 @ 3 1/2″ Lag Replacements
• A few thumb tacks
• 1 Gallon @ Sherwin Williams Flat Promar 200 Latex in Tricorn Black

DIY Screen Preparations

I started by taping off where my screen would live on the wall. In addition, I went ahead and put down a drop cloth to prepare for painting. Because light shines through our acoustically transparent screen, we should use both a black backer and paint the wall and frame black. Could I get away without the painting the wall? Maybe…but why risk it. I needed to paint the frame anyway…the wall is easy in comparison. I just used a roller.

The French Cleat

The French cleat as been a favorite way to attach things to a wall for…ever? I managed to miss getting pictures of building mine, but essentially the French cleat will be a 1×6 that we rip using a table saw at 45 degrees. We can then attach one half to the screen to provide extra cross support and hang it from the wall. The other half will be attached to the wall. This gives us an easy way to adjust the level of the screen and make sure it never falls off the wall. Since I didn’t get a picture, here’s a basic design of what it would look like and you can see the wall portion attached in the photo above.

Frame Construction

Once we cut down the poplar using our miter saw, its time to build the actual frame. To do so, we use the Kreg pocket screw jig and screws. These provide amazingly strong joints, specially for right angles. You see them used everywhere from cabinetry to just laminating wood.

I decided to construct my frame in the room since it was 12ft long and was going to be difficult to move. I started with the basic outside frame and then added cleats to the top and bottom. Then I made my way across with the 1×3 supports.

Once I completed the frame, I mounted it to the wall using the previously discussed French cleat. This seemed like a better plan than painting the pieces prior to assembly or painting it outside of the room and carrying it in.

Screen Material

Now that the screen is painted (and dry), it’s time to mount the black backer. I chose to do this in place rather than on the floor. Sure it required a ladder, but it was easier than attempting to work on it in my room which had chairs limiting the room available to work. I started with the black material.

Once the materially was loosely in place, I went from the center out on the top like you would with upholstery. I did this on the bottom and then the side, making sure to stretch any creases out. Luckily it stretched great and didn’t require ironing or steaming for me.

I purchased a Milwaukee M12 stapler and it was such a great purchase. Poplar is a hardwood, and as such…is hard. Harder than I thought it would be honestly. The poplar was very challenging to get a tack in while the electric stapler didn’t flinch and the battery lasted forever.

The final step is to stretch the screen material on. I had my dad helping me as an extra set of eyes to watch for wrinkles as I stapled it. I followed the same process as the backer and started with the top and worked my way out from the center. I didn’t go all the way across the top, bottom or sides. I worked out from the center on all four to make sure I didn’t end up with wrinkles. The UF material doesn’t really stretch much, so you just have to go slow and be careful as you make it around. Once complete, it looked like this:

Conclusion

I didn’t take as many pictures as I had intended, but hopefully this was helpful anyway. I’m impressed with the quality of the Seymour clothe and how easy it all went together. Next up…it’s time to build a riser!

As I began down the journey of my first home theater, I spent a ridiculous amount of time researching the different screen options. But the more I looked, the more disappointed I was at either the size, cost, or gain of the screens available. My room is 18′ deep and 13′ 6″ wide and I wanted to maximize my screen size. Not only that, but I wanted to have my speakers behind the screen and I wanted enough gain that I could do HDR without brightness issues. Let’s start with how to decide what size screen you should have and how I decided to build a DIY Screen.

DIY Screen Size

If you ask 100 people on the AVSForum what size screen you should have for your theater, you will get 200 different answers with most starting off with two words: it depends. And it depends really does sum up the quandry of screen size in a home theater nicely. It depends on how immersive you want the experience to be. It depends much depth your room has compared to the throw distance of your projector (and future projector). It depends on the width of your room and where you want your speakers. It depends…you get the point.

I started off my trying to figure out “the right” size screen for my room size. That took me down the rabbit whole of looking at the Society of Motion Picture and Theater Engineers (SMPTE) recommendations and then the THX recommendations and then reading the AVSForum…a lot. The SMPTE recommends a viewing angle of 30 degrees. This means you pick your main viewing location and either do some complex math or you a calculator from the internet. Doing the math for my room using a 14′ viewing distance (in between my first and second row) left me with a sad screen size of 90″.

Then I moved on to the THX recommendations of 35 degrees. This, I thought, sounded more promising since it would at least be bigger than 90″. Doing the math again I was left with 109″. Sure, they make 110″ screens, but it just didn’t seem big enough to me. And this is where we get to endless searches on AVSForum. And the recommendation there was interesting…just try different sizes and find what works for you. I found this to be refreshing as I was trying to hard to look at recommendations instead of just seeing what I liked.

So…I taped off my wall with the biggest size I could fit in my space and it came out to 165″. Now that sounds like the right size. And as I sat in my chair taking in the size, I thought…this is perfect, for me! Many people might think it’s too big, others might think its not even big enough, but it worked for me. But now I had a problem…if I had my screen that wide, where would I put my speakers?

Speaker Placement with a Large DIY Screen

I had a great idea of what my size screen would be…which was awesome, but now I had no idea where to put my speakers. With my screen size, I would only have about 8″ on either side of the screen. I also had a height problem. My screen was 24″ off the ground the way I designed it, so now I have to figure out where my center channel would go. This led me down the seemingly crazy idea of an acoustically transparent screen. This would allow me to get three matching speakers behind the screen and even put them at the right vertical level of the screen.

I’m going to be honest…I had no idea that was even a thing when I went down this path. The more I read about it, the more awesome it sounded. So I had to try that! The problem was finding a screen that would be the right size and not break the bank. The best option I found was a 150″ Silver Ticket screen that had pretty good reviews. But it was smaller than I really wanted and it wasn’t exactly a budget item at roughly $1200. So I kept looking. Then I stumbled upon the DIY Screen sub-forum at the AVSForum.

There were a number of people building their screen using materials like milliskin spandex or buying material from screen manufacturers. There were even a few people getting tons of samples and doing comparisons. The more I read, the more interesting it became. Acoustically transparent screens very commonly have texture which can be visible at certain distances. Even spandex, which has virtually no texture has the downside of having a much lower gain (which makes for a dimmer image).

In the end, I happened upon the Seymour AV website where they have an entire page and how-to guide on building your own screen. I cross-referenced this to all the threads I had been reading about materials and found that the UF material that they sell was perfect for my needs. It had a higher gain and spandex, was much taller allowing me to build a 165″ screen, and was readily available. Even better…it wasn’t obscenely expensive. It was only $13.95 / linear foot. For my screen, that meant the material was only going to cost $181 plus shipping. Even better than that, they answer their phone and are extremely helpful.

In my conversations with them they helped me decide on the right material (which was in fact the UF) and even gave me some helpful tips on painting the frame that I was going to build and getting a black backer material. They sold such a material, but it was going to cost almost as much as the screen material. I had found another backer material on clearance at the Silver Ticket website for $60 and rather than trying to sell me on their product, they readily said “get that, you can’t beat that price.” That was pretty refreshing.

Brightness for HDR and Your Screen

Obviously I’m a fan of Seymour AV, but there are other great options out there. I seriously considered the spandex route, but I needed 120″ wide material to build my 165″ screen, and due to supply chain issues, it just wasn’t available. And honestly, it wasn’t much cheaper than the Seymour product. But, more importantly, it didn’t have nearly the gain of the Seymour product. But wait…why do I care about screen gain? I would start by reading this article, as it goes into a lot more detail than I will here. In short, screen gain is the ratio of light reflected by the screen. So if you have a 1.0 gain, it reflects the same lumens that your projector is firing. If you have a .8 gain, it reflects 80% of the lumens back. The higher the gain, the brighter the image.

Again…why do I specifically care? Bright isn’t always better, but it does have importance in today’s home theater. With HDR being supported by more and more projectors and content, brightness matters. While projectors can’t really do “real HDR,” the brighter the image on your screen, the better job it does simulating HDR. So it can be helpful to understand your projector choice when you are picking a screen material. In my case, I was targeting the JVC lineup at the time (before the new laser models released) or the Epson lineup. The Epson 6050 UB was my choice, which had a light output of 2800 lumens. By contrast, the JVC that was closest to my price range was the NX5 which only had a light output of 1800 lumens. So I figured I would shoot for the higher gain screen in case I went that direction.

Designing my DIY Screen

Now that I had decided on a fabric to use and a screen size, the only thing left was to design the frame to support it. Luckily, the AVSForum wins again…thanks to MississippiMan. He posts in the DIY Screens sub-forum all the time and answers questions and helps the community massively. He was kind enough to provide excellent feedback on my design. There are plenty of options like a flat frame, frames made from metal, frames made from wood and spring loaded frames. In the end, I decided to go with a wood-based frame as I’ve spent more than my fair share of time woodworking and had the tools necessary. So…here’s the design he helped me finalize:

The outside structure that supports the frame is made from 1×4 Poplar. The inner supports are 1×3 Poplar. The top and bottom horizontal cleats are 1×4 Poplar. The French cleat is a 1×8 ripped in half at a 45 degree angle to hang the screen from the wall. It’s much like building a wall from hard wood. You need enough support to stay square and rigid while stretching and attaching your fabrics. The cleats on the top and bottom are key to keeping it nice and rigid. The French cleat helps as well. The actual DIY Screen design itself was built using my favorite tool: SketchUp.

Next Up, The Screen Build

While I was planning on this post to be my one post about building a DIY Screen, there ended up being more background than I had anticipated. So…it’s time to split the post into part 1 and 2. In the next post, I’ll show you how I built my screen, what tools I used, and how long it all took. In the meantime, here’s a sneak peak of what it looks like when you get done: