Installing and Setting Up Your A/V Receiver
By Michael Riggs
Pay special attention to where your new A/V receiver will live. Its amplifier section may produce quite a bit of heat and therefore needs adequate ventilation. Place the receiver on a shelf with at least two inches (preferably more) above its vents. If it has a fan, whether on the back or on the side, be sure not to block it. Otherwise, your new baby will overheat and might shut down or be damaged. Your receiver is the hub of your home theater system. Accordingly, it must be in a central location where it can be reached by interconnecting cables from other components and by speaker cables. If possible, place it so that the back panelwhere most of the jacks are locatedis easily accessible. At the top of your equipment stack is a good spot.
ConnectivityPretty much everything is a connectivity issue with a receiver. First, hook up the speaker cables, because that affects the physical layout of your system. Then do the interconnects to other electronic components, such as your DVD player. Save the AC cable for last, but don't plug it in till you've hooked up all the speakers. Never hook up speakers with the amplifier turned on. If you cross the speaker leads, you probably will blow at least one channelpossibly more. Let's look at some more specific connectivity issues.
Speaker CablesYour receiver will have at least one or two sets of relatively large terminals that are designed to accept speaker wire. Some models use only wire clips, which accept bare wire or pin connectors. Better models usually have binding posts for at least the front left and right speakers. Binding posts normally accept bare wire, pins, banana plugs, and spade lugs (which resemble hooks), though some omit support for one or the other of the last two. Bare wire and spade lugs provide the securest connections, because they have the large contact areas and can be clamped down tightly. Snugly fitted banana plugs are almost as secure, however, and much more convenient when you need to disconnect and reconnect for any reason. (If the binding posts for the positive and negative sides of each speaker connection are spaced _ inch apart, you can use double banana plugs, which make life even easier.) Wire clips make decent connections but are neither as convenient as bananas nor as secure as bare wire or spade lugs. Although there is a thriving market in premium speaker cable, there is no real technical or sonic imperative for using wire of unusual construction or exorbitant price. Ordinary stranded copper wire (lamp or zip cord) is perfectly satisfactory provided that it is not too skinny. (The thicker the wirewhich corresponds to lower gauge numberthe less its resistance to the passage of electricity.) The thinnest wire you should consider using is 18-gauge, but since 16-gauge costs only slightly more and is scarcely less flexible, we recommend it for everyday use. For long runs (more than 15 or 20 feet), especially to low-impedance speakers, you might consider moving up to thicker 14- or even 12-gauge cable. If you do, just make sure whatever you buy is reasonably flexible; such thick cable can be too stiff to handle easily if it isnt braided to maximize flexibility. And if you intend to run any wire through walls, make sure it meets local electrical codes for in-wall electrical cabling. If you are making bare-wire connections or adding your own terminations (banana plugs, spade lugs, etc.), go to the hardware store and invest a few bucks in a decent wire cutter/stripper. It will resemble a pair of pliers with notches for cables of varying thickness. This will save a lot of aggravation. Be sure that your receiver is compatible with the speakers you attach to it. Primarily, this means ensuring that their impedance is not lower than the receiver is designed to handle. Just about any decent receiverincluding those that indicate you must use speakers of 8-ohm or higher impedancewill work fine with speakers with impedance ratings of 6 ohms or greater. In the event your speakers are rated at 4 ohms, however, you should check with the receivers manufacturer if there is any question. (Unfortunately, the warning labels on the receivers themselves are often excessively conservative, to meet UL requirements.) Otherwise, you may find that your system will not play as loud as you would like or that the receiver overheats sometimes and shuts itself down; in extreme cases, it may even be damaged.
Video InterconnectsAs if life werent confusing enough already, youll find that three different types of video connections are in common use today: component, S, and composite. Component-video connections offer the highest picture quality. Only top-end A/V receivers support this type of connection, however, along with some DVD players, DTV receivers, and TV sets. Use them if you have a digital television set or a high-end analog set with component inputs as well as source components with component outputs. Component-video connections are made with a trio RCA phono jacks, color-coded red, green, and blue. You can buy pre-bundled component-video cables, but three ordinary 75-ohm video cables (often color-coded yellow) will work do the job as long as they're of the same length. Don't use audio cables, however, since they do not have the correct impedance. S-video is a small step down from component in quality and a fairly large one up in convenience. Connections are made with a single multipin plug and socket. Look at the plug carefully to find the notch and plastic pins that orient correctly in the socket. Then push gently and firmlybut only when you're sure it's going in straight. Almost all A/V receivers now support S-video switching for at least one or two inputs. The only VCRs that consistently have S-video connections are S-VHS models, but you can expect almost all other common video sources, including DVD players and satellite TV receivers, to have S outputs. Similarly, very few current-model TV sets or displays with any pretension to quality lack S-video inputs. Consequently, this is likely to be your workhorse connection. Composite (not to be confused with component) is the lowest-common-denominator video connection. It is the easiest to make, requiring only a single 75-ohm coaxial cable terminated with RCA plugs, but a significant step down from S-video in quality. On the other hand, pretty much any A/V receiver, video source component, or TV set you can lay your hands on will support at least this type of connection. As with component video, be sure to use 75-ohm video cables, not ordinary audio patch cords.
Audio InterconnectsGenerally speaking, every selectable input on your receiver will have an associated stereo pair of analog audio inputs, which will be ordinary RCA jacks. Be sure to connect these for any analog source components, such as VCRs, cassette decks, and so forth. You may or may not want to connect them for digital sources, such as CD and DVD players and satellite TV receivers. If you have enough digital inputs, you will probably find it more convenient to use them instead. And in the case of components that deliver Dolby Digital signals, such as DVD players, you will have to use a digital connection to get discrete multichannel surround sound. If you want to make analog recordings from a digital source, such as from a CD player to a cassette deck, you will normally need to make the analog connections even if you intend to use a digital link for normal listening. This may also be necessary for recording to digital recorders through the receiver, if the receiver does not supply a digital recording output for this purpose. One important thing to note is that turntables (those things used to play vinyl phonograph records) must be connected to a special set of analog inputs labeled "phono." If you connect it to one of the other (line-level) inputs, the sound from the turntable will be bass-shy and very low in level. All of the other analog inputs are the same in terms of their electrical characteristics, and you should use those for connecting analog sources other than turntables. Still, you will find it reduces confusion to match input names to sources as much as possible. That is, connect your CD player to the input labeled "CD," and so forth. Recording devices, such as cassette decks, should be connected to inputs labeled for recorders or "Tape." These will usually have an associated set of outputs to feed signals from other sources to the recorder. Most receivers also have one or two inputs labeled "Aux" or "Auxiliary" to handle miscellaneous analog sources. As with speaker cables, you will find no shortage of opportunities to spend extravagantly on analog audio interconnects. But unless you need very long cables or have unusual interference problems, the ones that come in the boxes with your components will work fine and sound as good as anything else you could buy. Whats important is that the cables be well constructed and shielded and that the plugs fit snugly into the jacks. For very long runs, it is desirable that the cables have low capacitance. Gold-plated connectors offer superior corrosion resistance if both jack and plug are so finished. To the extent possible, try to match gold plugs to gold sockets and nickel plugs to nickel sockets, as this will yield the most reliable long-term connections. Digital audio connections come in two flavors: coaxial and Toslink optical. It doesnt matter which type you use, so long as its the same at the source and receiver ends. That is, coaxial outputs mate only with coaxial inputs and optical only with optical. Coaxial digital connections should be made with 75-ohm cable, which normally will be labeled for video or digital audio use; do not use ordinary analog audio patch cables. Optical connections are made with special fiber-optic cables. The digital inputs on most receivers will automatically detect what kind of signal is coming into them and respond appropriately. Some, however, may have only one or two digital inputs that can accept Dolby Digital signals. In that case, make sure to attach Dolby Digital sources, such as DVD players, to digital inputs labeled for Dolby Digital (often with the double-D Dolby logo). If your receiver does not have enough digital inputs for all your digital audio sources, you may have to depart from the comfortable hub-and-spoke model of "receiverdom". For instance, you may plug the digital output from your CD player directly into the digital input of your CD-R recorder, the CD-R's analog output into your receiver, and monitor or play recordings that way. A/V receivers normally have a line-level output generally labeled "subwoofer output" designed to feed the input of a powered subwoofer. If you have a powered subwoofer in your system, connect it to this output. You may need to buy a long interconnect cable for this purpose. Even if the sub has two line inputs, one connection will usually do. Finally, a good rule of thumb: Connect outputs to inputs and inputs to outputs. Never connect an output to another output!
Upgrade OptionsMany A/V receivers have six-channel analog inputs designed to accept the output from an external 5.1-channel surround decoder or from multichannel music sources, such as DVD-Audio or Super Audio CD (SACD). Simply match the output jacks on the decoder or player to the multichannel input jacks on the receivers and run ordinary audio interconnects between them. Some receivers have preamp outputs that enable you to feed a system in another room or to upgrade by using more powerful external amplifiers in place of the amps built into the receiver. (If these are connected to the internal amplifiers by jumpers, you will have to remove the jumpers before proceeding.) Again, simply match outputs to inputsin this case, preamp outputs to amplifier inputs.
Special ConnectionsTo get Dolby Digital out of a laserdisc player, you will need either an AC-3 RF input on your receiver (a rare feature) or an external AC-3 RF demodulator to go between the laserdisc players AC-3 output and one of your receivers standard digital inputs. Plug the LD player's AC-3 RF output into the matching input on the receiver or external RF demodulator. Note that on laserdisc players the AC-3 output is separate from the standard digital outputs. If you have a turntable, its delicate low-voltage signal should go only into the receiver's phono input, which typically will accept moving-magnet phono cartridges (a few receivers switch between this and the moving-coil type of cartridge). The turntable's ground wire should go into the receiver's ground terminal to prevent hum. Hook up the AM and FM antennae supplied with your receiver (the AM antenna may be built in) into the appropriately labeled terminals. The receiver's FM input may be either 75-ohm (which typically accepts an "F-type" RF connector) or 300 ohms (accepting bare wire or spade connectors). An adapter, if needed, will likely be supplied with the receiver. Consult the manual. Your receiver may require additional connections for CD-synchro or other control functions. Again, follow the instructions in the manual.
OperationWhen you first turn on the receiver, try the FM tuner to see if you can get any sound from the speakers. This is a good place to start because the speaker connection is less prone to errors. In fact, even FM static will do if you need only to verify that the speakers work. The next step is to turn on each signal source (DVD, VCR, CD, etc.) and make sure its picture or sound output goes through the receiver to the TV and speakers. Also make sure recording devices (VCR, cassette, etc.) are able to get signals from the receiver. All A/V receivers incorporate what is known as bass management. That is, they allow you to apportion where the bass in the various channels goes according to the capabilities of the speakers. This is possible because we tend to localize sound sources based on middle and high frequencies more than low frequencies. In any event, your first order of business once youve established that the receiver is functioning more or less correctly should be to go into its setup menu and adjust the bass management. Normally this will consist of indicating whether or not there is a subwoofer in the system (subwoofer on or off) and what the bass capabilities of the front left/right, center, and surround speakers are. (Assuming the system has center and surround speakers. If not, these should be set to "Off" or "None" in the menu.) If a speaker has limited low-frequency extension or output capability, you should designate it as "Small." Almost all center and surround speakers fall in this category. Speakers with good bass capability may be designated as "Large," but if you have a good subwoofer in the system, you may find that you get best results with all the main speakers set to Small. If there is no subwoofer in the system, you should make sure that at least the front left and right speakers can handle a decent amount of bass and be set to Large; otherwise, you will get rather disappointing sound. If you plan to use your receiver's surround capability, you'll need to adjust the channel balance among the speakers. Using the remote, activate the receiver's internal test signal. Adjust the center and surround channels so that they are the same level as the front left and right speakers. A sound-level meter (such as the Radio Shack model, catalog number 33-2-50) can be a helpful and inexpensive way to guarantee the accuracy of your settings, which are critical to good surround performance. Set the meter to C-weighting, slow response and hold it so the microphone is at seated ear height at the listening position, pointed toward the ceiling. Then fiddle with the level settings on the receiver until the outputs from the speakers in the system are as close to the same as you can get them. Some receivers (including all THX models) include a test signal for calibrating the level of the subwoofer, which is extremely useful. If your receiver doesnt supply such a signal, consider getting a good setup disc, such as the Delos Surround Spectacular (DE 3179) or the Chesky Stereo and Surround Sound Set-Up Disc (CHE151). And try to resist, at least at the beginning, the temptation to crank the subwoofer level way up. Once youre used to correct levels (that is, ones that match what the producers of the recording or soundtrack intended), you probably will find hyped-up bass overbearing and fatiguing.
Finally, you will need to adjust the delays to the surround speakers and possibly to the center speaker. Your receivers manual will have explicit instructions on how to do this.