Wiring the A/V Rack Wall

You Need Tools to Pre-Wire

The tools you need to complete the pre-wire job are dependant on the type of pre-wire you need to install: new construction or retro. New construction pre-wire installations are much easier because the wire is installed before the sheet rock and insulation. You have complete access to the stud bays and attics. Retro custom installations are a little more difficult because you need to fish wire in pre-existing walls with the sheet rock in place. In some cases, you may need to cut the sheet rock to provide access for the wire run, then patch and refinish the sheet rock.

Basic Tool List: New Construction

• Heavy duty corded or cordless drill
• Wood boring, auger, or paddle drill bits
• Hammer
• Ladder
• Camera
• Various hand tools like screw drivers

Basic Tool List: Retro Custom Installation

• Heavy duty corded or cordless drill
• Wood boring, auger, or paddle drill bits ( may need longer lengths)
• Fish tape or fiberglass fish rods
• Bright Flashlight
• Ladder
• Various hand tools
• Roto zip or drywall saw
• Dry wall patching tools
• Dust Mask

Retro pre-wiring can be dirty, frustrating, and sometimes dangerous. If you don’t have the skill and knowledge to perform the various tasks or if you are unsure of your ability, my best advice is to hire a competent A/V installation professional.

Let’s Get Busy (A/V Rack Wall)

Now that we have established the location of the audio/video equipment in the room and have the tools to complete the job, it’s time to get our hands dirty. The photo shows typical stud framing of an exterior wall with the wall studs installed 16-inches on center. Partitioned interior wall may or may not have blocking installed between the studs as illustrated in the photo designated by the letter “B”. As previously stated, if you are pre-wiring new construction, blocking will not present a problem because you have access to the inside of the stud bay to drill holes in the blocking. If you have a retro pre-wire you may have to cut out the sheet rock to drill through this blocking to run your wire. A quick word about drilling holes in stud framing before we proceed. As a rule, I never drill more than two holes with a maximum size of 1-inch in a stud bay. The reason for this is because it could potentially weaken structural stud framing. In the picture, you see only two holes for each stud bay with the holes drilled in the center of the 2x4 blocking. The same rule should apply for drilling through the framing top plate of the wall. If you are not sure about the local code regulations, you may want to consult with your local planning and building department.

Low voltage work boxes as illustrated with the letter “C” should be large enough to accommodate all of your wire. Note the location of the low voltage boxes in the photo; they are installed above the high voltage romex electrical circuit to prevent RF electrical interference. A good rule to follow when pre-wiring your home theater is to always keep your pre-wire as far away as possible from high voltage electrical wire. Looking at the photo you will see that high voltage romex is also installed vertically in the stud bay as illustrated with the letter “D”, there is no pre-wire installed next to the romex that runs vertically up the wall. Instead, the wire is installed in the next stud bay.

If you have a retro installation, you should locate electrical outlets on the wall and high voltage electrical romex wire runs before you drill into the stud framing. Nail plates are installed everywhere the pre-wire goes through the stud framing as illustrated with the letter “E” The nail pates prevent the wire from being damaged if a nail or screw is installed in the wall after sheetrock is installed. Flex tube conduit is installed in the wall as illustrated with the letter “A”. The conduit is left empty and provides access for future wire pulls for future expansion. This low cost item is often over looked in high end home theater pre-wire installations. Electrical outlets as illustrated with the letter “F” also need to be considered. You need not spend your money on “audiophile” electrical outlets but should install commercial grade 20 amp outlets. The reason for using the commercial grade outlet has nothing to do with sound quality: that’s all BS. The main reason is that commercial grade outlets have better grabbing power. The tangs used in the commercial grade outlets will hold heavy power cords better than conventional 15 amp “El-cheapo” outlets. Partially dislodged power cords can create system hum and buzz so spend the extra $2 for the good outlets. The last thing I want to mention about the photo and illustration is how the wire is installed. It hangs gently with no sharp bends and comes out of the low voltage box as a trunk of wire.

For my dedicated home theater room, I installed allot of extra wire because wire is relatively cheap and you never know what you will need for future upgrades. Starting with the speakers I wired for the main left, center and right speakers. Additionally, I ran wire for an alternate pair of front speakers and an additional center channel. I also installed five runs of RG6- QS just in case I ever acquire self amplified speakers. For the subwoofers, I used two Blue Jeans LC-1 pre-terminated subwoofer cables. I pre-wired two additional RG6-QS cables for the future. For the surround sound channels, I pre-wired for two side mounted surround speakers, two optional surround speakers at the back of the room, and two EX channels. I ran two RG6-QS cables to the rear corners of the room for future upgrades. When you have completed the speaker pre-wire runs, lightly tack the wire to the back of the wall for any wall mounted speakers and leave an additional 2-3 feet of wire to pull out of the wall after the sheetrock is installed. Now that you have completed all of your in-wall pre-wire, take photographs of all your wiring in the stud faming. This will help you locate it after the sheetrock is installed. Pick a central location and record measurements to the location of each wire or mark the measurements on the floor where the wire is located in the wall. All of the future upgrade cable should be neatly coiled in low voltage boxes.