Okay, so you’ve been working away for months to design your home theater, get your room built, and choose some great gear. Now it’s time to put all the ingredients together and actually spend time enjoying it. You should be at the stage where the actual construction of your theater room is complete, but it’s an empty shell. You should have a bundle of wires wrapped in plastic wrap coming out of the wall at the equipment location. At the speaker locations you’ll have either a mud ring / electrical box for a wall plate, or new construction rough-in brackets for in-wall or in-ceiling speakers. At your display location you should have a either a mud ring or electrical box with your video and control cables. If you did use electrical boxes instead of mud rings (where code permits) you’ll now know why it was such a good idea to cut the back off the box at the pre-wire stage. The final trim-out and hook up will be much easier.
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Before you start pulling the wire and cables out of the boxes, you need to install any acoustic paneling you may have planned. You’ll need to cut out the panels to allow for any switches, receptacles, or wall plates. It’s not terribly difficult, but there are much better ways to spend a Saturday afternoon. If you are installing acoustic paneling, find a clean place in which to make any panel modifications your theater room may require. These panels are made of fiberglass, so make sure you use appropriate safety attire when making any panel modifications. You don’t want to breathe in any of the fine glass particles or get it in your eyes or on your skin.
Typically the panels will come with a resin hardened edge. If you have to cut this edge, carefully (very carefully) unwrap the acoustic fabric from the edge of the panel you need to cut. Use a table saw to cut the panel. This will help ensure a straight cut. If you are making a curved cut, use a quality jig saw. The resin portion of the panel will cut like a hard wood, but saw will go through the rest like the proverbial hot knife through butter. After you’ve made your cut, you need to cut the fabric to fit the panel and re-wrap it.
If you only need to cut out a few holes for outlets or switches, your job is much easier. Very carefully measure the location of the required cutout and mark the center of it. Mark the edges and then cut the fabric in an â€œX” from corner to corner. Don’t remove the fabric, you’ll need it to cover the edges of the hole. Gently pull it back and then cut the underlying fiberglass in the required shape.
After the cutting operation is complete, you need to re-wrap the edges of the panels that you modified. You have a choice here. Either you can wrap them as they are, or you can recreate the hardened edge. The latter is nice, but difficult to achieve. If you leave the edge unhardened, it will be difficult to get a nice, straight consistent looking edge when you are finished. If you do choose to re-harden the panel edge, use fiberglass resin, available at a home warehouse store or plastic supply house. The stuff is nasty, so be careful. It also stinks while hardening, so be sure you close the doors into your house, or you could find yourself in a spot of trouble. If you’ve ever done any work on boats, you’ll know what you have to look forward to. It’s not as critical to harden the edges of cutouts as it is for long panel edges, so if you’ve only cut those, you can probably skip the hardening step.
After every thing is all cut and refinished, you’ll need to hang them. Most of the acoustic panel manufacturers ship the panels with wall clips for installation. The clips are mounted to the wall and then the panels are impaled on the clips. Alternatively, you can use construction adhesive, such as Liquid Nails to hang the panels. The adhesive route works very well, however, be very sure about placement before you begin. The adhesive method is rather permanent, and will leave big chunks of panel / adhesive on your wall should you ever remove the acoustic panel in the future.
After you’ve installed any acoustic paneling, it’s time to begin installing any wall plates and in-wall or in-ceiling speakers. In the construction industry, this is known as the â€œtrim phase”. There are several styles of wall plates to choose from. The modular type with square holes or ports to allow several different types of wire to be installed in the same plate has found favor for this application. You can get inserts for almost any conceivable low voltage wire application, from CAT-5 or CAT-6 network, to speaker jacks and coax fittings. They come in the â€œDecora” style or a traditional all in one plate design. Decora is a two piece design, with a rectangular center section that actually has the inserts, and and a surround section around the outside. If your house has the large, Decora rocker-style light switches, you will probably use this type.
These modular type plates are also available in the traditional style, wherein the port inserts are located in the wall plate itself. Most large home warehouse stores have these type of wire plates. They are made by most of the major manufacturers, including Leviton and Lutron. At your video display and main equipment locations, it often works best to use a wire access plate. This is merely a plate with a single, large hole and a flange for the wire to be routed through.
You can also install any in-wall or in-ceiling speakers into their brackets at this stage. Check to see that the speaker bracket is clear first. Often the drywall is cut incorrectly, or there is some drywall mud in the bracket. Once everything is clear, pull out about two or three feet of speaker wire to give yourself some room to work, and cut away the rest. Hook up the speaker to the appropriate terminals, and install it in the opening. If your speakers didn’t come with a back box, it can really help to damp the drywall around the speaker to avoid drywall resonance problems.
You can use a flexible acoustic back box from Dynamat or Acoustibloc for damping. They can be rolled up and installed through the drywall opening. Both have impressive performance. As an added bonus, they will almost completely kill any back wave radiation into ceilings or adjoining rooms. If you don’t use these, use some stick on damping material, such as Dynamat, on the drywall surfaces inside the wall cavity around the speaker.
After you’ve got all the plates installed, it’s almost time to start actually hooking up your equipment, but not quite so fast. You’ve come this far in your quest for home theater ecstasy, it’s no time to take short cuts. Before you hook up any amplifiers, you should check all your speaker wiring for continuity. This will ensure you don’t have a problem with an expensive amplifier or receiver due to a short in the wiring caused by an errant sheetrock screw or nail. This happens on occasion, even if nail plates were used to guard against it at the pre-wire stage. If possible, you should do this after the drywall has been installed, but before mud and tape, but sometimes the construction schedule prohibits it. In any case, you should perform such a test immediately before any equipment is hooked up.
Once you’re sure of your wire / cable integrity, you can begin the hook up. Plan everything carefully. You don’t want to start cutting the cables to length, only to find a piece of equipment can’t go where you thought it could. If your cabinet has rear access to allow a clean, well dressed wiring job and easy service, you’ll be much better off. If you’re using a, equipment rack that is recessed into the wall, use one that pulls into the room to allow neat wiring and easy service in the future.
Next time we’ll cover the actual equipment hookup and such essentials as wire management, documentation and labeling.