Low Voltage Home Pre-Wire Guide:

General Features and Wiring Layouts


In this section:


Feature/Layout Description:

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Our new house is about 6000 square feet (we are finishing about 4000 sf, but wired for the future to cover the other 2000 in case we can ever afford to finish it all). Most sources recommend a central location for "home-run" wires, providing greatest connection versatility. Home-run speaker wires, for example, allow either all speakers in the house to carry the same music (with impedance matchers and/or multiple amplifiers with the same audio source) or, with more expensive audio distribution equipment (future enhancements?), zoned music to allow different music in different rooms depending on the wishes of the room occupant. Home-run phone lines allow the use of central PBX systems (such as the Panasonic KX-T30810 phone system) where each phone has its own extension number. Centralized phone lines still allow multiple phones on the same extension by common connections at the central punch-down blocks, or even full-house single-line connections, but provides flexibility in changing the configuration that would not be available in more conventional daisy-chained phone wiring schemes. A central home-run twisted pair wiring scheme for a Local Area Network (LAN) allows star-configuration network connections (10BaseT, etc.) anywhere in the house. Home-run video cables allow either single-source video distribution via signal splitters and video amplifiers, or sophisticated multi-source video distribution with the right equipment. In any of these cases, the simpler less expensive alternative are available to start, but more sophisticated (and expensive) alternatives are open for future enhancements; flexibility is the key.

The ideal might be to have everything, including audio, video, phone, and data, going to one central location; Node 0 in CEBus lingo (actually, CEBus uses "Node 0" specifically for hardware that does switching and connecting at the central location, but I use it here to indicate the location where such equipment would be installed). However, we wanted our audio equipment to be located in our media room for shortest wire length to the most critical listening area and for greatest local control of the equipment. There was no clean way to put all the other equipment (future LAN servers, video distribution equipment, phone PBX, security control system, etc.) in our media room, so I chose to put a second node in the basement for video distribution (not source, which stayed in the media room), phone and LAN. The security system was put in yet a third location to make its location less obvious to an intruder. Therefore, our Node 0 is located in the basement, but we have a central "Node 1" for audio distribution, and a third smaller "Node 2" for security. Nodes 1 and 2 are connected via appropriate wiring to Node 0. A/V equipment is linked to Node 0 via three coax and three signal-level cables from Node 1; video sources are switched in the media room and piped to the basement for distribution. The signal-level cables could be used in the future for keeping a PA-system or separate whole-house source system (music source) in the basement and piping the results up to the media center for audio distribution.

I had discussed with consultants a further breakdown to separate some of the whole-house audio into first-floor and second floor systems; this could be done acceptably by sending the source audio signals through high-quality shielded signal-level cable from the media room to an upstairs central amplifier location for upstairs distribution. This would have reduced the number of wires going all the way downstairs to the media room, but would possibly reduce future distributed music possibilities. Both consultants said this would be a viable alternative if only single source audio distribution was desired, but I opted for the more versatile central audio distribution.

We purposely did not install an intercom system. We preferred the higher quality of the whole-house audio system instead of piping music around with the intercom. And we liked the greater versatility of using the Panasonic PBX phone system for paging (using speaker phones) or ringing all phones in the house to have the other person pick up on any phone to talk. The phone system will also be used with door phones so a visitor can push an outside "doorbell" button, ring all the phones in the house, and we can talk to the visitor from any convenient telephone. We may also use the system to allow us to answer someone at a driveway gate from any phone, and enter a code on the phone pad to remotely open the gate for them. Why use an intercom system, introducing yet another piece of equipment?


Media Room / Home Theater:

Media Room Layout

The media room is the location of our main audio and video equipment. We built the room with an equipment stack (shelves) on the left wall with a standard room door through the wall behind the equipment stack shelves. This door, accessible from the exercise room on the other side of the wall, allows us to easily get to the back of the equipment to arrange and re-arrange the normal jungle of patch and interconnect cables associated with A/V equipment. On one of the side walls inside the shelf area of the stack, we had the framers put in a vertical "plenum" from floor to ceiling (7" deep) so we could run all the whole-house and media room A/V cables to the ceiling of the media room (the floor is concrete slab, but I had previously run a 2 " electrical conduit from the stack area to the basement for future changes/enhancements). On the shelf side of the plenum wall, I put two double-gang wall boxes, one about 14" above the floor and the other about midway up the wall (about 45" from the floor). The backs of these boxes were cut off, giving about a 4" square hole in the wall at each height for all the wires. On the exercise room side right next to this equipment stack was a closet, so I put two similar wall boxes low in the closet for "spill-over" equipment, such as whole-house amplifiers and/or impedance matchers, infra-red control boxes, etc. -- things that do not frequently need to be seen or operated manually. With the plenum of wire in between the shelves and the closet, I can move the ends of the cables from one location to the other, or run any needed patch cables between the two locations. Even with all the cables run to this location, the media room shows a clean stack of equipment and all the interconnect cables can be easily accessed and neatly organized from the exercise room. We ended up with more than 80 in-wall cables altogether at this Node 1, for the media room and whole-house audio. If all the cables were tied together tightly in a single bundle, it would be about 4" or 4 " in diameter.

For electricity to power the equipment stack and the room, two dedicated 20 amp circuits were run by the electrician. One is to power just the equipment stack, and the other is to power the whole-house audio amplifiers and the media room wall outlets. I had the electrician put two switched circuits in both the equipment shelf wall and the adjacent closet. One switch provides power for the equipment stack (one outlet in the shelf wall and one outlet in the closet) and the other switch provides power for the whole-house audio system (another outlet in the shelf wall and another outlet in the closet). In addition, a third outlet in each location provides non-switched power, giving me a total of three outlets in each location (triple-gang wall boxes). This way I can turn on all the equipment in the stack with one switch, with or without turning on the whole-house audio system. The switches and shelf outlet box were located on the shelf wall opposite the cable plenum to ensure electrical noise does not interfere with all the cabling.

We currently have an audio sound processor, and may someday upgrade to a audio/video sound processor. Since I don't know whether we might get THX sound or 70MM, in addition to Dolby Surround Sound, I tried to wire for all possibilities. Our current sound processor and a few others (notably Yamaha) use two front effect speakers, and most all also (or only) use two rear effect speakers. However, THX systems are supposed to use side effect speakers, located at the same room depth as the listener. Each of these speakers has a "double" driver (cone), one angled toward the front of the room and the other angled toward the rear, so the sound always comes indirectly to the listener. The listener sits in the "null" position. Each speaker box (containing the two drivers) is driven with one set of external wires like a normal speaker, but they are usually set in a "dipolar" connection internally, so when one driver is pushing, the other driver is pulling; they are 180 degrees out of phase. A switch may allow them to be driven either in-phase or out-of-phase, as desired. Anyway, to cover the possibility of using this type of speaker for THX effects, I installed wires to the expected listening position on each side wall of the room (about the same distance from the front wall as I expected the chairs or couch to be). In addition, I installed speaker wires to high wall locations in front for front effects speakers and also high on the rear wall for rear effects speakers. All effects speaker wires were located so the speakers could be mounted 7 ' from the floor (we have a 10' ceiling in the media room). I put two wall outlet boxes low on the front wall for floor standing main speakers (right/left), and ran heavier speaker wire to them. A center-channel speaker cable was run to a center outlet box, the same one used for TV cables. And, finally, I installed signal-level wires (not speaker wires) to the right front corner (floor level), and to the left rear corner for the possible addition of a sub-woofer. I used two locations so that we could test for the best sound after the room was finished, and use the best location for whatever sub-woofer we got depending on the final room acoustics. Since the sub-woofer is expected to be the normal self-amplified type, the signal-level wires were used instead of normal speaker wires, and an electrical outlet was provided near the sub-woofer jacks to power the speaker.

We currently use a 35" tube television monitor for our main TV, but may someday upgrade to a larger rear-projection monitor or a lens projector. For the current TV monitor and possible rear-projection TV, I ran three runs of coax and three runs of signal-level stereo wire for the antenna, external 1, and external 2 input to the TV (coax for video, signal-level wire for right/left audio). I also ran a high-quality pre-terminated Super VHS (S-Video) cable for clean signal from satellite or our SVHS camcorder. This was a standard pre-made Monster Cable level 3 S-Video cable, 8 meters (about 25') long, purchased again from SoundTrack (expensive - about $100). Finally, SoundTrack recommended running a 4-conductor 22 gauge stranded wire cable to major TV locations for possible ELAN or AudioEase control, so I ran this too. All these cables, including the center-channel speaker cable, were run from the equipment stack through the wall studs to the center of the front wall, where I put another cut-off double-gang wall box. I left the cables long enough to extend into the room a few feet so I can just directly terminate them for TV connection.

In case we can ever do a real home theater with a ceiling-mounted lens projector monitor (triple-lens tube projector or LCD projector), I ran cables according to SoundTrack's and Listen Up's advice. I used four coax cables (for Red, Green, Blue, and Sync signals -- or, any one could be used for composite video instead), two signal-level cables (stereo audio in / audio out), and a 22-gauge 4-conductor cable for ELAN/AudioEase compatibility. I also ran a 22-gauge 8-conductor (4-pair) wire between the projector location and the ceiling above the front wall for a 12-volt signal from the projector to control an electric projection screen to drop from the ceiling (optional). Actually, a 16-gauge 2-conductor wire was recommended for this, but I had the 22-8 and can always double up the conductors. I had the electrician install two electric outlets in the ceiling, one at the screen location and one at the projector location. The guideline the consultant told me to use for the projector location was one and a half times the screen width back from the screen. For example, if you use a 6' wide screen, the projector would be mounted 9' from the screen. Since it is unlikely that we will install such a projector in the near future, I just "buried" the wire in the ceiling and took photographs of its location. I ran the wiring between the ceiling joists from mid-room along the length of the room toward the back to ensure that I could later get to the wire regardless of what distance from the screen I ended up putting the projector. I just suspended the cables between the joists and made them long enough that I could cut a hole in the ceiling, reach through and pull the ends of the wires back to wherever the hole ended up. That way I could decide on the screen width (and therefore the distance back from the screen for the projector) at a later date.

Since the equipment stack is on the side of the room, it may be possible that an infra-red (IR) remote may not be able to hit all the equipment well. Also, since some of the equipment may be put in the closet next to the stack, it may not be accessible to IR. Therefore, SoundTrack suggested adding an IR receiver on the front wall -- I put it high on the wall to one side to make it out of the way of a projection screen if we put one in. Also, since we may want to control the equipment using IR repeaters in other rooms of the house, I put an outlet high on the wall opposite the equipment stack (right wall) for an IR blaster. Actually, I plan on trying a device called "Leap Frog", which is a small unit that attaches with velcro to the front of an IR remote control, intercepts the remote's IR signals, and converts them to a radio wave (RF) signal, which is transmitted to a receiver in the media room equipment stack. The receiver then converts and re-transmits IR signals to the equipment via small IR transmitters (up to four extenders) that are placed in front of the equipment. A friend of mine uses this system and says it works great! It is inexpensive -- about $50-$60 for the receiver and one remote control attached converter, about $15 for each additional remote converter. However, in case this does not work in our large house (the transmitters are claimed to work up to about 100'), I did the wiring for an IR repeater system (similar system, but IR receivers are mounted in the walls, convert and transmit the signal via hard wire to the equipment stack base unit, and converted back to IR transmitting to the equipment via equipment-mounted IR transmitters or the IR blaster across the room from the equipment). This same wiring can also be used for multi-zone control keypads in the future.

I also ran a special satellite cable from the media room stack to the outside for a big dish satellite (we live in the mountains). In case we decide to use DSS or Primestar at some time, I also ran two coax cables into the attic where we can later run them outside for these small-dish satellite systems. And, since our new location can receive a couple of local stations, I ran a coax and a rotator wire (Radio Shack, about $5) to the attic where we have room to install an antenna.


Whole-House Audio:

Whole-house audio was run from the media room's equipment stack / closet location. SoundTrack's design, based on successful installations in numerous houses of different scales, is to use is to use speaker switching boxes that switch from 4 to 8 speaker pairs off one (or two) amplifier(s) using impedance matching transformers, NOT resistive loads. The design of these impedance-matching boxes is claimed to result "in no power loss and maintains the amplifier's damping factor", according to one manufacturer's specifications. These switch/impedance matcher boxes are made by several high-end audio companies, including Sonance, Xantech, and Niles, so I believe they should work well. Wiring is run from the audio source to this switch box, then one cable set to a room-located volume control (which is a stepped transformer, not a variable resistor), then from the volume control to each stereo speaker. Using this type of system, you can listen to several pairs of speakers driven by the same amplifier without harm to the amp. Of course, you may need a powerful amp to drive several pairs of speakers, so multiple amps might still be a good idea if many speakers are to be driven at once. An A/B switch in some rooms allows the expensive in-wall speakers to be used as higher quality speakers for local audio sources, such as enhanced TV sound from TVS that have an amplifier built in for external speakers, or a small stereo system used just for that room.

Growth potential lies in the ability to add equipment for zoned audio, where someone in one room can listen to a different audio source than someone in another room. Using the same centralized audio wiring scheme, multiple amps and switchers are used for the sources. Each audio zone has a keypad that is used to select the music source, and the selected source is switched to the requesting volume control/speaker system(s). This type of system is very expensive (the zone keypads alone, depending on capability, run from about $250 to $450 each!), so we will not use it unless the prices come down quite a bit. However, with the same wiring, simpler (and cheaper) systems provide some limited control. For example, using an infra-red repeater system, an infra-red receiver (about $75-$85) can be put in the wall box and use the same wire to transmit to an IR blaster (about $65) in the media room, allowing control of the single-source audio from anywhere an IR receiver is installed. An IR remote is pointed at the IR receiver in the desired room, and the command is transmitted to the IR blaster in the media room to allow control of any piece of equipment in the stack. More sophisticated IR control systems are also available. There are also keypads that mount in the same wall boxes that just emulate a learning IR remote; you "teach" the keypad the IR commands (like programming a universal IR remote), and punching the pre-labeled keys then transmits the command through the wire to the same IR blaster. This avoids lost remotes and looks more professional, but the keypads are still about $250 each. In summary, lots of different methods of control are available using the same keypad/IR wiring in the house. BTW, this type of control is called IRBus by CEBus.

I also ran signal-level cable to special TV outlet locations in rooms where we might some day want to provide a secondary source for whole-house audio. For instance, in the library we might want a stereo system where we can change CDS while we sit and listen in that room. To allow the rest of the house to listen to those CDS also, the signal could be piped to the media room from the library and switched there to the whole-house amplifier(s). SoundTrack actually specified this cable to be run to each TV location for possible signal-level sources to be sent to each TV, as a possible scheme used by ELAN or AudioEase. However, since this is not yet a standard, I don't plan on using ELAN or AudioEase, and this is the most expensive wire we bought, I limited this type of cable run to just the library. But, it is something to think about.


Powerline, Video, Phone, and Data:

The design for video, phone, and data is based on CEBus specifications where they made sense to me. Since the "workhorse" of CEBus is the Powerline bus (PLBus), I made the assumption that if it would work with X-10, it should work with CEBus. Therefore, I did little with the high-voltage design other than having the electrician bring power to the light switches and then run the switched leg to the light, instead of running power to the light and the switch leg to the switch. This ensured that power (and ever-present signal path through the switch boxes) was available at each switch location regardless of the switch location; it ensured that a neutral wire was available at each switch box (needed for florescent or high-current X-10 switches). The electrician was already familiar with X-10 installations, so I left most of the details to him. See the section Surge Protection and Bridges for other X-10 considerations.

CEBus uses coaxial cable for TVS, FM receivers, security cameras, etc.; they call this the CXBus. It consists of two coax cables in parallel to each outlet. The External cable is used for external sources such as cable TV or satellite, and the Internal cable carries internal sources such as VCR and camera signals. Other sources also recommend two coax cables to each outlet, and suggest that until a fully accepted standard is common one coax could be used for cable/satellite and the other for a central video tape player, allowing some inexpensive source selection at the TV via input selection on the TV.

CEBus uses twisted pair wiring (TPBus) for phone, data, and programming (like HiFi or an intercom). They talk about using the TPBus for stereo sound, but I chose to use the 16 gauge speaker wire scheme since it was more familiar to me and matched my consultant's successful experience. To ensure adequate future expansion of either voice or data, I ran two 4-pair TP cables to both TV and phone locations. This usually gave me at least two outlet locations (one TV outlet box, one phone outlet box) in each major room and bedroom at which I could connect phone, data, or both. I wanted to reserve one 4-pair cable for possible high-speed LAN connections (which could possibly use all 8 wires in the case of 100MBit LANs), and to ensure complete separation of data cross-talk, and use the other 4-pair for multiple phone extensions and/or low-speed LAN or other data links (such as a short-haul modem for non-LAN printer distribution, etc.). CEBus specifies separate 4-pair cables for phone and TPBus to avoid unwanted signal pick-up between phone and other services. This wire is relatively inexpensive (5-10 cents per foot, depending on category; see the wire type/cost chart). I know one person who ran 25-pair cable to each room to allow for RS-232 serial connections, etc., in addition to category 5 LAN 4-pair cable to each room.


Schematic of Typical Full Room Wiring:

- ASCII Schematic also available.

The above layout is what we typically used for a bedroom or the library; other rooms had more or less the same, depending on use. The top half shows the whole-house audio connections in a room, sourcing from the media room Node 1. The bottom half shows video, phone, and LAN sourcing from the basement Node 0. In the diagram, the cable runs are numbered in the form xxg-y, where "xx" is the wire gauge and "y" is the number of conductors. The dotted lines surround one or more devices or wires that we put in each electrical wall box. For instance, both the volume control and the A/B switch were put in the same double-gang wall box; the keypad went in its own single-gang (or double-gang) wall box.

A four-conductor speaker wire cable was run to the volume control, then to an A/B switch if that room had a second audio source (such as a TV's external speaker connector or a secondary stereo system). Two separate two-conductor speaker cables were then run from the A/B switch (or directly from the volume control if no A/B switch was used), one to each stereo speaker. Where an A/B switch was provided, another four-conductor speaker cable was run to the wall box where four banana jacks (2 for right, 2 for left) were to be placed for the second audio source. This was usually the same (double-gang) wall box to which the video cables were run since this location would probably be the best place to put a small secondary stereo system, or we could use a TV's (amplified) external speaker connection as the secondary sound source.

The 22 gauge 4-pair cable was run from the media room to all rooms that might need an infra-red receiver or a future music zone source selection keypad. This was a single-gang box in smaller locations like bedrooms, or a double-gang box for more key areas, like the Great Room or Library, where a larger keypad with more features may be desirable.

The two coax cables, the phone cable, and the LAN cable were run together from the basement to the TV wall box location. From this box, the phone and LAN were usually looped through the box then run to the phone wall box location. Allowing access to the phone and LAN cables from the TV box provided an alternative location for either service, but only if needed. I will probably just leave these wires looping through these boxes and not terminate them unless I find I need them, but at least they will be there if it proves convenient. Since my phone wall boxes were usually located across the room from the TV box, this allowed greater distribution of the cables. I still used only a double-gang box in the TV locations (one outlet for both video connectors, the other for the four audio banana plugs used for secondary A/B switch source) since Leviton has a wide range of data/phone modules that could be used if the data or phone cables are later needed. Leviton's Telcom Category 5 line and QuickPort® products allow just about any needed configuration of F connector jacks, phone, category 3 or 5 modulars, BNC, or even fiber optics; up to four mix/match jacks can be put into one outlet device or single-gang box.

See the Telephone and Cable Outlets section for more on wall jack options, which might influence the type of boxes you install.

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