The Withrow Build (Erskine Design - Equipment from everywhere)

Hey Folks, I've been a long time AVS member and have learned a lot about home theater on the forum. I am just finishing up a theater build that culminates a journey from a Sony G70 crammed in a third floor room to a dedicated build from the ground up. It was designed by Dennis Erskine and built by my contractors. For better or worse, I selected pretty much all of the equipment and made a few tweaks to Dennis's design along the way. However, most of it was aesthetic. While the process was challenging, I learned a lot and am very pleased with the results. I hope some future DIYers will find some nuggets of info that are helpful for them. I'm going to err on more pictures than less, just because I always like the threads with lots of pics.

The theater was part of a larger addition that included a garage, workout room and bathroom, and a new master suite. I'll focus on the theater, but the early pictures show the initial construction of the addition for what it is worth.















Next, the insulation, whisper clips, hat channel ...
Edited by Ben Withrow - 6/20/12 at 9:27pm

The journey continues ...

As noted above, we went with whisper clips, hat channel, and double layers of 5/8" drywall with our gooey friend - Green Glue - in between. Definitely go with the dispenser, as it is well worth the money, but a pain the ___ to clean. We had to clean it many times during the build, but just once per day when it was used. It was really weird to feel how dense the walls and ceiling were and still be able to make it flex by pushing on it. The clip system does allow for a good bit of flex, at least at this point.

The first of three floor layers was 3/8" rubber acoustic mat. It comes in 4' X 25' rolls. I thought we were really moving at this point, but this was back in November. Last time I checked, it was June 20, and we are just finishing up. The second and third layers are 1/2" OSB and 3/4" OSB,respectively, with GG in between.

Now that the three floor layers are down, we started on the riser, which doubles as a broad band bass trap and the stage. The riser is just under 16" tall. I've seen many riser calculations, but my experience has led me to believe that most of those estimates are low. Go as high as you can. It looks great and works even better, now that I've got to see it in action. It was initially spec'ed to be 12", but that just seemed to low at the time. I'm really glad that we went higher. It ended up being nice because the riser seems near the high of the seat part of our chairs, which give a cool look. You'll see some openings cut into the riser for three 4" X 36" bar-type diffusors.





The riser below has three layers of OSD (3/4" + 1/2" + 3/4) with GG in between. Trust me, contractors love multiple layers of anything. Putting GG glue between the layers really solidifies the relationship. We all better now.

As shown below, the rest of the addition was moving along nicely.



The theater is located just off of the kitchen where a screened porch was located. We really like having the theater so centrally located and accessible. Multiple people have commented on it. Decoration time ...
Edited by Ben Withrow - 6/20/12 at 5:20pm

The theater has several columns that are mostly for looks. However, the two rear columns got the sub treatment. Each one has one a JL Audio Fathom IWS (13.5" driver). They each come with a separate 2000W amp that is located in the equipment room. The following pictures show how we built the boxes for the columns and how we installed the subs in the columns. These subs are amazingly and interestingly engineered. They have a sealed enclosure that hangs from a pendulum, which is inside my column. They work great and absolutely don't rattle the column or wall and still produce great bass - amazing. The IWSs are balancing subs. I'll have two JL f113s up front for a total of four subs.



The columns below are just the plan Jane columns for decoration - I ran out of sub-money.



Below are the rear-sub columns getting ready to be hung on the wall. Everything on the walls are hung on the walls. The columns and the walls that will see below that go between the columns are all hung on the drywall, so as not to touch the floor.



As the columns were going in, the framework for the soffits and the coffered ceiling was being installed. To avoid penetrating the shell, all of the wiring, lights, HVAC ducts, speakers, etc are inside the shell in the coffered beams, soffits, or wall (not yet shown) that go between the columns.




The duct work was real tight. We got it to work, but that should have been planned out better initially. The HVAC system ended up being inaudible, but more on that later.

Speaker time - well, kind of. Dennis originally spec'd Procella speakers for me. I'd never heard them, and being very concerned about the musicality of any speaker, I needed to hear them before I bought. As such, I went to CEDIA and demo'd the P6s and a bunch of others. They had great dynamics, but they didn't get me excited enough. It could have been the room. I also had Dennis send me a set of P8s to my house for an audition. Still no love. Dennis then sent some Triads up, but I was really having an issue with compression drivers etc. that are often found in "theater speakers." My first love is music, and against conventional wisdom, I was determined to make this a room in which I can truly enjoy music. Not spoil the happy ending, but I did accomplish the goal.

I went with Wisdom Audio in-wall speakers all around. To me, they may be the best speakers that I've ever heard, and they really shine in the Dennis's theater. I actually went to Carson City to demo the speakers. I was given a three hour demo by the president, and had numerous chats with Jon Heron. Great company, amazing speakers. The reason I mention this now, is that I needed to build boxes for the speakers and hang the boxes on the walls, as you'll see below, along with many other trim, HVAC, and dampening tasks.

The front speakers are 72" tall. You can see the three boxes as well as one of the HVAC supply plenums - by the way, the theater is on its own zone and has two returns and two supplies. Each has a big, insulated plenum, which has insul-shiled inside.

Below you can see the "wall sections" that go between the columns going in as well as the start of the screen wall and the prosceniums. The prosceniums are a cool idea of Dennis's. They look great, but they actually function to block sound from the L and R speakers from reflecting off of the front portions of the side walls. I was a little anxious to see how they worked, but they work very well. The entrance to my AV closet is behind the left proscenium.

You can also see where I had earlier painted a screen on my from wall to make sure how big of a screen I wanted, where it should be centered, and the aspect ratio,

This was one of the most important design experiments that I have done. I was slated for a 144" wide 2.35:1 screen. After some experiments with my old RS!, I just didn't like how small non-scope movies looked. There are a lot of 1.85:1 movies and IMAX docs that just looked puny to me on the scope screen. I really stressed over this one, Dennis and other AV folks fought me, but I went with a 1.89 ratio screen that is 141" wide. The ratio is for 4K and a match for the 4K Sony 1000ES that I ended up with.

The screen size and aspect ration just matches the room nicely.



The last two pictures show the resulting panel openings that will get stretched fabric. The 2X4 that lines the panels is for Quest fabric track, which by the way, is a top-notch product.

We added some overlay moulding around the panel openings and the recesses in the columns for a consistent look.


Edited by Ben Withrow - 6/20/12 at 6:25pm

Time to paint. The interior decorator did a great job picking out the colors, carpet, and fabric. My wife found the sconces. I found the seating. This whole process was pretty interesting. Before we even started with Dennis, I just wanted a black man cave with great audio and video. I didn't care much about the aesthetics. But, my wife did, and the challenge was for the decorator to come up with a color scheme, with our control-freak selves, that would look good, but not hurt the video. The decorator tried a bunch of dark colors, but she wasn't happy until she gave up and settled on black, with some nice accents. So here go the paint ...Black is a touch color to photograph, but it looks much blacker and nice in person. We ended up with a custom block from Sherwin Williams in a Duration type of Matte (not flat) paint after lots of experimenting. The first pictures are just of the primer. They sprayed everything, and the room really seemed like a cave.



Once we put a thousand coats of paint on it and the painters were hanging with the Green Glue group of irritated contractors, we laid the carpet.



In the background, you can see the first of two layers of JM Insul-Shield that covers the wall behind the screen wall and the back of the prosceniums. The plastic is a 3 mil poly that they put between the 1" layers of Insul-Shield. The Insul-Shield is pretty pricey, but comes with a textured black backing that is designed to be exposed and provide a nice looking surface for those shadowy areas. It doesn't need to be covered - looks good.

Next, I installed the Quest AI treatments per Dennis's plans. They seem to work great and look very high tech - for what that is worth. If you zoom in you can see that there are different types of treatments all over the place. Some just absorb, some absorb and diffuse, some absorb, diffuse, and refract.reflect. The look cool enough to make think they should work




Now, for the fun part, speaker time.

As noted above, I went with Wisdom Audio Speakers. The fronts are L75s, which are line arrays using a planar magnetic ribbon. The four surrounds are P38is. All of the speakers are bi-amped and require an external DSP that Wisdom provides (for money). The first picture is one of the four P38is. The following pictures are of the rear drivers for the JL IWS sub-woofers. You don't install the drivers until the end of construction. After that, you can see the inverted L75i where the 48" ribbon is on the bottom and the four woofer bass module is on top. The center speaker is also an L75i, it just happened to be covered the GOM FR701 by the time I took the pictures. I didn't want the ribbons to reflect light back through the screen. You can see the front subs (JL fathom F!13s) behind the L75is. The L75is are mounted in the boxes you saw earlier. The boxes are mounted in the screen wall. You can also see that the screen section of the screen wall is recessed about 9". The sides of the recess are covered with Stewart Filmscreen's Velux, which is the exact material used to cover there frames. The frame is a square tubular frame from Stewart and is mounted in the opening. The light from the flash makes the materials look different, but in reality, they look seamless.



The screen is a 141" ST130 microperf. This was another one of those really stressful decisions for me. From the info on the forum, I was very concerned about using a microperf screen. I love audio, I love video, it just seemed like a huge compromise. Plus, I could never find a good sample of the Stewart microperf, and if I did, it was with a subpar projector or audio setup. Once I heard the L75is, I new that was the speaker I had to have. The L and R from speakers are not behind the screen, so it was just the center behind the screen. The Wisdom Audio folks highly encouraged me to go this way. Dennis would have shot me, if I had not went with the microperf and the center behind the screeen. So on faith, I went where many have said is AV h*ll. In short, it works unbelievably well. I wish I had all of my lost sleep back. The picture with the Sony 1000ES is awesome. What I did notice when I played with my RS1, was that the pixels on a large screen were much more of a problem than the holes would ever be. I wonder if people are seeing pixel texture and thinking it is the holes. I sit very close, 12' back from the 141" wide screen. The RS1 showed pixillation, the 4K is perfect. I can't say enough about what a great screen the ST130 microperf is. My old screen was a non-perf ST130. If there is much of a difference, you would really have to AB them in the same room.

The big lesson, having the voice come from behind the screen is awesome and there is no real video hit from my perspective, and I'm picky. The DSP fixed the slight roll-off above 11K, and the sound is awesome. DON'T FEAR THE MICROPERF FROM STEWART (this one was for you Dennis, thanks for being so stubborn.)



Here is a sound isolation door that Steve Kajula, who works with Dennis built. Great build quality. It weighs close to 250-300 pounds. I don't have the seals, which came with it installed yet, due to some final painting, etc. The door is a laminated 1 3/4" door with an MDF facade that matches the other doors in the house. Well done Steve. He is an awesome dude - more on that later.


Edited by Ben Withrow - 3/15/13 at 11:04am

Now the finale ...

Last Friday, Steve Kajula, who implements all of Dennis's real theaters came up to install the Quest fabric track and stretch the fabric for the screen wall and the panels. The seating just happened to come in the same day. I felt like a kid at Christmas.

The colors are not very accurate, but you can get an idea of the theme. In person, the carpet isn't as washed out and the fabric has a more rich, bronzish look.



After much thought and testing on seating, I went with an unknown brand to me - IMG Norway. I stumbled across these seats in Highpoint NC at Furnitureland South. These are the most comfortable and supportive theater chairs that I have sat in. I checked out everything from Fortress to Lane. These seats are very well made, but the real kicker is the adjustable headrests and the ergonomics of the chair itself. The headrest slides up and down AND tilts in, as you can see a little bit from the pictures above. This feature allows you to recline and adjust the headrest so that you can easily view the screen and rest your head on the rest. I really encourage people to check out these chairs. Great stuff - built in Norway with German motors. The three interior arms have storage compartments and an cool hinge that allows the arms to slide back about 5" to reveal cup holders. I'll try to get picture of that posted.

I still have some work to do, but we are very close. The next step is to get a more comprehensive calibration of the DSP for the audio. I also want to thank all of the great folks who helped male this happen. I'll dedicate a post to those people when in the future where I list who they are, what they did, and why they are great.
Edited by Ben Withrow - 6/20/12 at 9:29pm

21' wide X 25.5' deep. Ceiling is 10' up front.

The path to the Wisdom Speakers was started after hearing how surprisingly natural voices sounded on a par of Martin Logan in-wall speakers. I think the Wisdom Speakers made the audio easy. If you have two rows of seating, the line arrays of the L75is are very nice, as they attenuate at half the rate of point source speakers. It is very apparent once you experience it. Note that most ribbon speakers are not line arrays. The P38s that I use for surrounds are point sources.

We used plywood on the bottom and MDF for the sides. I was a little worried about using MDF, was talked into it, and it worked well. All molding was pine.

I'm in Cary. I didn't know there was an NC crew. I don't know too many folks who care about this stuff.

I did an exhaustive search and test for chairs, fortress, etc. These are the best I've experienced - still love them. Everyone comments on how comfortable they are. Great, quiet, smooth motors. I bought mine at Furnitureland South, which will deliver anywhere.

The wisdom audio speakers are all bi-amped and require wisdom's SC-1 DSP, which uses a pro grade Audessey setup and some other goodies. The crew I bought the speakers from did the calibration.

The black looks better in real life than the pics. The decorator picked the fabric, and I can't remember the name or brand. I'll try to figure it out. It isn't a standard GOM type fabric. Dennis said any fabric that I could breath through would work. He was right, so a lot of options opened up.

I had to figure everything out and work with the subs to exhausting degrees on every single step. As for the joists, you build a band around the perimeter of the platform with double 2x material that is staggered and standing on its side. We used 2x6 and 2x12s. The staggering keeps it strong and helps with the seal. Then, you span the opening with the joists. I'd go bigger than 2x6 joists and 12" centers or you'll get too much flex even with three OSB layers. Big subs will make the bass trap come to life (too much maybe).