Saga of the "Old Vic" - Page 5

With the HVAC complete and an annoying plumbing leak that meant ripping down the wall and ceiling of a downstairs bathroom (above the theater) I was ready for closing up the room. BTW you will never guess the cause of the leak.... the previous home owner had hung a large painting on the wall with a beefy nail. Unbeknown to them they had hammered it right into a 4" drain pipe. It probably sat for years like that until I moved in and removed the nail... The thing is that it was not obvious where the leak was. Result: another weekend wasted re-drywalling a bathroom!!

Back to the theater build. Like a fellow builder (KNKKNK) I'm building a completely free standing room within a room. Consequently that needed a little bit of shear support. I was always planning to add OSB sheathing to two of the walls and ceiling for this purpose, but I made a mistake: I carefully made a spreadsheet for all the flat materials I was going to need in the next phase (OSB/Drywall/MDF). The spreadsheet was for one layer and of course, I was doing DD and GG so I doubled it.. The result was delivery of a much larger stack of OSB than I anticipated:



The OSB is pretty cheap so it was more cost effective to just use it and cover every surface. (Sorry KNKKNK, I wasn't intending to duplicate you on this one).
Also, I wasn't satisfied with the feel of the dricore on the lower level which will be carpeted -- I'm very sensitive to spongy/springy feel. Therefore I decided to add a few more tapcons to the dricore and layer additional 3/4" subfloor with a layer of green glue in between. I'm really happy with the feel now, so I don't care whether or not there are acoustic benefits to this.



Even though it is just OSB, the room has a strange warm feeling to it. It's sonic character has also change quite dramatically now -- when I dog visits me and barks the ringing is painful to the ears.

Whlist adding the OSB I also came up with a cunning plan (Black Adder quote there). As I've described previously I'm building a IB sub in the front 3' of the room. One (perhaps the only one) of the disadvantages to an IB is that it is practically impossible to move it around to tune the base. Most IB builders use a parabolic equalizer to help tune the response but I'm taking a slightly different approach: You see I have two perfectly good Klipsch KW-120-THX subs as part of the Ultra 2 set I purchased on ebay last year. So, in a classic case of utter overkill I'm going to put the IB sub at the center of the front wall (4x18" drivers BTW) *and* the two Klipsch subs at the center of the rear. I'm then plan on using a Audyssey SVS AS-EQ1 to optimize the dual subwoofers. More on this as it unfolds. It will either be crazy good or just plain crazy. We'll see.

Anyway to prevent the rear subs from getting in the way I opened up the rear wall and made a recessed area in preparation:





Whilst talking about subs, I have decided to attempt another first (as far as I know) and mount the IB sub on the sand filled stage. The rational is to avoid directly coupling 4 x 18" drivers to my walls but instead to mount it to the stage and then build/seal the wall around it. The process is going to be a little tricky but I have a plan that should unfold in the coming weeks.

I have been in the spending mood lately. My IB sub drivers arrived a few weeks backs (4x18" Fi drivers) and I hope will pair nicely with the back Klipsch sub(s):



I also put in the order for a Middle Atlantic rack. I've opted for the full height pull out AXS design like this one.



It's going to be nice, but boy are they expensive

Bringing my thread almost up-to-date.

I got a nice delivery of 10' 5/8 drywall (the correct amount this time):



And out came the green glue:



I wasn't happy about starting this phase. 10' 5/8" drywall is heavy stuff to work with alone. Here is the proof for the kids and family:



The drywall lift is an amazing invention but I wonder -- has anybody had the steel cable snap? I'd hate the think of the consequences and it certainly makes some creaking sounds.

Right now the drywalling is about half done. I'm just closing up the first layer...

You mean you want a laugh! Actually I've already managed the first layer. I cheated and cut the couple of sheets in half, fitted the wall sheet first 3/4" from the ceiling then rested one end on the top of the wall sheet and levered it up whilst standing on the pile. It could have gone wrong and I would have ended up covered in green glue but I got lucky. By the time I get to the second layer the pile should be gone.


I'll watch the cable .. now I'm going to be even more nervous with every creak and groan. Maybe it wasn't such a good idea to buy the cheapest one I could find.

Yes, although the room is feeling smaller with each layer! I guess I could have dug it even deeper...

Thanks Brad,

I'm looking for quality LFE first, but don't mind a bit of skin melting too

Great idea on the GG application. I've just finished a beer lunch and now I'm going back down to hang a few more sheets and will try out your idea...

I had a couple of people PM me and so thought it time for a little progress report. Whilst I'd like to say I was completely done with dry walling, the reality is that it is almost there. It has got to be one of the most monotonous boring parts of the whole build Still got to hang the second layer in one little closet, build and skim the IB sub divider wall and then do a final tape/mud/seal.

Here are some pics. The first is especially for BIGmouthinDC who was wondering how I would drywall the ceiling above "the pile". Well, I manhandled one side as previously described and then got creative (if a little reckless ) on the other:



Before fitting the drywall I installed the inner door (I'm building communicating doors). It's a 1 ¾ solid core fitted to an 5 ¼ external frame. I choose a paint grade flat style to maximize sound stopping ability and to allow me to dress it up to match the theater décor.

The 5 ¼ frame depth allows it stand proud of the framing by 1 ¾ which represents the ½ OSB and two layers of 5/8 drywall.



The temporary blocks of drywall were so that I could align it perfectly flush.



Now all I had to do was drywall tightly around it. Typically you would mount the door after drywall and the result would be a larger than necessary gap around the edges. With a bit of forethought and hanging the door first means that a very tight fit with the drywall which helps with the soundproofing.



One thing I don't want in the room is any sort of door threshold so I purchased an automatic door bottom from Ted White. I'm going to route and mount this inside the base of the door.



Speaking of Ted, I'm getting though the pails of Green Glue and boxes of caulk at an alarming rate. I had to order more. Unfortunately my local UPS are a bit rough and a couple of tubes were split. No problem though, replacements are on there way..

And this is where all that caulk went .. every seam in the first layer of drywall was well treated:



Then all panels overlapped in the second layer. I ended up buying some extra 8' lengths of drywall for the final ceiling layer so I could save the 10' lengths I had delivered for the entrance which also has 10' walls.



And I'm almost ready for mudding. Other than waiting for yet more Green Glue I still need to build the manifolds for my IB sub so I can complete the framing and drywall on the dividing wall. You can see the framing where that diving wall will be -- about 3' off the room length. I decided to build the dividing wall after to reduce the drywall work. I thought it would be easier to knock out the combined room first, then frame the divide rather than tackle it as two rooms.

Michael, you are soooo right. Can't wait to get to some interesting woodworking.

To break up the monotony of the drywall I've been fiddling at a couple more things. Firstly, in an attempt to make the raised door less of a trip hazard, I started to make the external step.



I stopped because I'm having second thoughts about laying a hardwood floor and step. I've seen a couple of fantastic builds where they used black marble tiles to form the entrance, one even made and inlaid a bronze Hollywood start. Here's the kind of thing that I'm thinking:



I'd have to rip up the dricore to do this so I'm going to ponder it a bit longer.

I also turned my attention to my equipment rack which arrived the same day as my latest electronic toy, a Behringer EP4000 (formerly known as the EP2500) amp which will power the IB sub. I assembled the rack so I could perform a trial fit in the closet.




I have plenty of room inside of the closet that will house the rack which will allow me to mount the network and phone plug panels to the inside walls - I don't have enough to justify installing a rack mounted panel. I would also like to close off the closet with a smoked glass door so I installed some ventilation in preparation. What you can see is a passive inlet below the closet that vents into the lower back. I intend to put a temperature controlled extraction fan in the top of the closet above the rack and vent either above the rack closet into same room or into the dead space above the theater ceiling joists. I'd appreciate some advice on this because vented outside the entrance would look nicer and get the additional hot air out, I was worried that the warm air would condense (remember the space outside the theater shell is a former crawl space) and create a moisture problem.

Actually Brad, you were part of that decision. I read your experiences just before I started the drywall. I'm really starting to appreciate the ability to watch a bunch of similar builds proceed. The only thing I wasn't sure about is whether I needed to drywall IB chamber side of the dividing wall. I also pinged Cathan on his reasoning behind drywalling both sides. In his case it was necessary as a result of framing the diving wall first to prevent flanking. As a result of my approach I'm just going to skin the theater side, probably with a layer of the "QuietWood" I still have lying around and then GG/DW.

If I can find someone who can mud/tap the room for cheap I might consider farming it out. I don't mind doing it except for the 10' ceiling which would make the process much slower without stilts. Anyway, I'm on a business trip for a week so I'll make that decision when I get back.

Talking about room skinning, I don't know if you are appreciating having that initial layer of OSB yet, but i'm in the process of designing the room interior and thinking about how each piece will be mounted and being able to attach anywhere on the walls/ceiling is going to be very valuable. BTW I love your backlit subs!

Well it's been a long time since my last progress photo journal and frankly things have been going pretty slowly on the theater - there always seem to be other projects stealing time. Here's one from a couple of weeks ago that included a bit of landscaping and building of an arbor around a deck. I'm pretty pleased with how it turned out and it's nice to work outside sometimes.



Anyway the basic theater drywall finishing is done. Here's a pic of the rear of the room showing the recess that will partially hide the rear subs. This was taken whilst the mud was still drying and before the awful sanding.



The media storage room / closet turned out a little smaller than originally planned, especially when the acoustic treatment is applied -- I'm thinking of making either some pull down of slide out DVD/BR storage racks. I hope I can make productive use of the space since it was quite a bit of extra work soundproofing and finishing.

To breakup the mudding and sanding I built my IB sub manifolds. I didn't photograph the process but there are plenty of similar designs on the forum. Basically they are two heavy boxes with routed holes for the 18" drivers. I used a sandwich of 3/4" ply and 3/4" MDF. One thing that I am doing differently is in the mounting of the manifolds. Typically the IB manifold is mounted to the wall framing. Whist convenient this directly couples the sub to the wall and I wanted to avoid this. The generally accepted theory for traditional box subs is to place them on a sand filled stage that is decoupled from the walls. I thought I'd adapt this approach for my IB sub. The only problem is that the stage would have to extend through the IB sub wall. My solution is illustrated here. I'd be interested what the experts think but I believe avoiding direct coupling to the wall has to be advantageous ... we shall see because it's too late now

Here are the two IB manifold mounted to part of the future stage (the part that protrudes into the IB enclosure) and the initial wall framing around it.





The partial stage is sand filled. The stage and IB manifolds are separated from the framing by a 3/8" air gap which will be later sealed on both sides with acoustic caulk. The picture also shows one of three speaker recesses made with the same 3/4" ply/mdf construction.

Completing the framing including the L/R speaker recesses. The ceiling plate and outermost wall stubs were set before the last layer of drywall for a really good solid seal:



Since the wall separating the IB enclosure and the theater will only be skinned on one side I was concerned about its strength especially given the
pressure from the back wave from the sub (isolation is not a concern since the outer wall is free standing). I was also concerned that major vibration
would eventually rupture the caulking around the manifolds. To solve this I added some steel bracing to attach the back wall to the IB wall:





My constant companion here has an annoying habit of sneaking off with my tools and parts. Whenever I can't find something it generally
turns up in the yard in a partially chewed state!

This pic shows the isolation of stage and IB manifolds from the wall:



And here is the caulking of the gap on the inside of the chamber (I plan on caulking both sides):

With the framing done, the wall can be skinned. I'm using a ply/DW combination (with the obligatory Green Glue). In this case I'm using some of
the QuietWood I got from a friend. This is a lamination of two layers of ply with a thin steel plate. It is certainly a heavy and damped material but the layer of steel makes it a b***h to cut:



My entry for the worlds largest jigsaw piece:



All seams caulked of course:



Before closing the area off I hung some of the pink fluffy stuff inside of the IB chamber. I'll probably hang some more on the rear wall as well. The addition of insulation has the effect of virtually increasing the IB enclolsure volume -- I'm at about 8xVas for the 4 18" subs I'll be using and 10xVas is ideal goal. I'll been told the difference will have minimal efect.



That pretty much brings me up-to-date. I'm in the middle of making some mounting brackets for mounting the sub drivers then after a test fit I'll drywall over the ply and seal the IB enclosure for good ;-). Actually I know a lot of builders leave an entry hatch into the IB space but I'm not going to do this because I'll be mounting the drivers from the inside of the manifold and I can easily crawl through the 18" hole after removing a driver. I doubt I'll ever have to do this but it's good to know there is a way in just in case....

Chadci, In2Photos, thanks for the feedback. I understand that the manifold design reduces stress by canceling opposing forces, but I doubt the result is completely vibration free? In any case it keeps things interesting to try something new . It's unusual to hear that the IB was actually less obnoxious outside the theater than you tube sub ... although my IB enclosure is airtight and isolated from the house right now, one experiment I *might* try in the future is to open it up by way of a removable plug to the rest of the crawl space making it truly an infinite space. It would then vent underneath the living room where it would be interesting to compare the difference in SPL levels.

Thanks Brad!

I managed to finish the wall today...



Here is what the "padded panic room" looked like before sealing up:



The speaker recesses are indeed to potentially gain another 8" of length and possibly to make a baffle wall easy. The one drawback is that you either have to build extra large recesses or work out the exact position of your speakers ahead of time. I hope I got it right. Also some speakers don't like this kind of mounting. Luckily I do have a set of Klipsch Ultra 2 speakers which are perfectly at home with a recessed mounting. BTW I have two each of the KL650, KL525, KS525 and the subs -- I purchased them used (and cheap!) on ebay a couple of years ago in preparation. I still need to get one more 650, but that is the plan for the LCR set. I may need to replace the KL525's with KS525's for the rear in which case perhaps I could experiment with Dolby PLIIz Hmmm...

I'm so close now to some fun woodworking. How is your soffit coming along?

I haven't run the wires yet but I plan on mounting the drivers in backwards so the terminals will be exposed. That was one of the reasons for this approach. However I can still get into the IB through one of the cutouts - I tried it and it feels quite claustrophobic in there!


That's pretty impressive and certainly makes a point but does this also mean that if you are using Submersive subs you don't need a sand filled stage (because there is no vibration to decouple)?