Your receiver is command central for your A/V system. Every other piece of gear in your system needs to be connected to it — in fact, some components require two or even three separate connections to your receiver! (The only possible exception is your TV, if you opt not to use your receiver for video switching.)
On the back panel of most home theater receivers, you'll discover a dizzying array of inputs and outputs at your disposal. Audio inputs will likely include analog stereo input, analog multichannel, optical digital, and coaxial digital options. You'll also have analog outputs corresponding to at least some and possibly all of these types. For video connections, you'll typically find three types of inputs and outputs — composite, S-video, and component video.
 The back panel of a home theater receiver offers a bewildering jungle of inputs and outputs to the uninitiated user. |
With so many ways to hook up your gear, the permutations of possible connection schemes are virtually endless. The ways you connect your components to your receiver, however, will have a big impact on your ability to do a number of important and fairly basic things with your system.
If you're using your receiver for video switching or dual-room/dual-source listening (both described later in this article), you'll find that some types of hookups will severely limit what you can do in these realms. Also, if you plan to use any form of recording gear — including a DVD recorder, a CD recorder, a VCR, a cassette deck, or a MiniDisc recorder — your method of connection will determine the flexibility of your recording options.
On the following pages, we'll present a series of connection tips aimed at helping you get the most out of your system.
Audio connections: the digital/analog divide
Home theater receivers typically offer a variety of digital and analog inputs for connecting your A/V gear. Digital components such as DVD players, CD players, and MiniDisc recorders almost always offer both digital and analog outputs, allowing you to plug them into either type of input on your receiver.
Many people assume that a digital connection will always yield the best possible sound. This isn't always the case, however. All digital signals must be converted to analog form before you can hear them. A digital connection delivers a signal to your receiver while it's still in digital form, and lets your receiver's DACs (digital-to-analog converters) handle the conversion. With an analog connection, your digital component uses its own DACs for the conversion, and passes along an analog signal to your receiver.
The type of connection that will yield the best sound for your system is largely dependent on which piece of gear has the most sophisticated DACs — your receiver or your source component. If you've spent top dollar on a high-end receiver and you're using a very basic CD player, you'll likely get better sound with a digital connection. If your receiver is an older model and you've recently invested in an advanced DVD/CD player — especially if that player offers SACD or DVD-Audio playback capability — odds are fairly good that an analog connection may actually result in more pleasing sound than a digital one.
It's a good idea to at least try out both digital and analog connections with each digital component in your system. When testing your DVD or CD player, listen to a CD that you're very familiar with using a digital connection, and then try it out with an analog hookup. Depending on your equipment, the difference may be subtle or it may be very noticeable. Even if you have a clear-cut favorite between the two options, you may want to leave both the digital and the analog connections in place. The reasons for this are discussed in the next two sections of this article.
Doubled digital/analog connections for dual-room/dual-source use
Dual-room/dual-source receivers are designed to let you listen to surround sound or stereo music in your main room while a housemate enjoys a different stereo source in another room. One of the limitations of preamp-level (non-powered) dual-source output, however, is that only analog signals can be sent to the second room. (This restriction does not apply to the powered dual-source output offered by some newer receivers.) This means that if you've got, say, your DVD/CD player connected only to one of your receiver's digital inputs, you can't listen to CDs in your second room.
Making an analog connection between your DVD player and your receiver easily solves this problem. However, unless your DVD player offers built-in surround decoding, you'll also need to hook it up to your receiver via an optical or coaxial digital connection to enjoy 5.1-channel Dolby? Digital and DTS? surround sound.
Home theater receivers typically make this kind of doubled connection easy to set up and operate. If you hook your DVD player up to, say, Optical Digital Input 1 on your receiver's back panel, you can then tell your receiver to prioritize that input. Once you've done that, whenever you switch your receiver's main-room source to DVD, it will automatically use the signal from the digital input, if one is present. (Most receivers can also be set to use the analog DVD input as a second choice for main-room listening, if no digital signal is present.)
The preamp-level dual-room/dual-source output, however, pays no attention to the digital inputs. When you select DVD for your second-room output, it will always use the signal coming into the receiver's analog DVD input.
Home theater receivers typically offer a variety of digital and analog inputs for connecting your A/V gear. Digital components such as DVD players, CD players, and MiniDisc recorders almost always offer both digital and analog outputs, allowing you to plug them into either type of input on your receiver.
Many people assume that a digital connection will always yield the best possible sound. This isn't always the case, however. All digital signals must be converted to analog form before you can hear them. A digital connection delivers a signal to your receiver while it's still in digital form, and lets your receiver's DACs (digital-to-analog converters) handle the conversion. With an analog connection, your digital component uses its own DACs for the conversion, and passes along an analog signal to your receiver.
 An analog connection uses your source component's digital-to-analog converters (DACs), while a digital connection bypasses these in favor of the DACs built into your home theater receiver. |
The type of connection that will yield the best sound for your system is largely dependent on which piece of gear has the most sophisticated DACs — your receiver or your source component. If you've spent top dollar on a high-end receiver and you're using a very basic CD player, you'll likely get better sound with a digital connection. If your receiver is an older model and you've recently invested in an advanced DVD/CD player — especially if that player offers SACD or DVD-Audio playback capability — odds are fairly good that an analog connection may actually result in more pleasing sound than a digital one.
It's a good idea to at least try out both digital and analog connections with each digital component in your system. When testing your DVD or CD player, listen to a CD that you're very familiar with using a digital connection, and then try it out with an analog hookup. Depending on your equipment, the difference may be subtle or it may be very noticeable. Even if you have a clear-cut favorite between the two options, you may want to leave both the digital and the analog connections in place. The reasons for this are discussed in the next two sections of this article.
Doubled digital/analog connections for dual-room/dual-source use
Dual-room/dual-source receivers are designed to let you listen to surround sound or stereo music in your main room while a housemate enjoys a different stereo source in another room. One of the limitations of preamp-level (non-powered) dual-source output, however, is that only analog signals can be sent to the second room. (This restriction does not apply to the powered dual-source output offered by some newer receivers.) This means that if you've got, say, your DVD/CD player connected only to one of your receiver's digital inputs, you can't listen to CDs in your second room.
Making an analog connection between your DVD player and your receiver easily solves this problem. However, unless your DVD player offers built-in surround decoding, you'll also need to hook it up to your receiver via an optical or coaxial digital connection to enjoy 5.1-channel Dolby? Digital and DTS? surround sound.
Home theater receivers typically make this kind of doubled connection easy to set up and operate. If you hook your DVD player up to, say, Optical Digital Input 1 on your receiver's back panel, you can then tell your receiver to prioritize that input. Once you've done that, whenever you switch your receiver's main-room source to DVD, it will automatically use the signal from the digital input, if one is present. (Most receivers can also be set to use the analog DVD input as a second choice for main-room listening, if no digital signal is present.)
The preamp-level dual-room/dual-source output, however, pays no attention to the digital inputs. When you select DVD for your second-room output, it will always use the signal coming into the receiver's analog DVD input.
 If you've got a dual-room/dual-source receiver, a doubled digital/analog connection with your DVD/CD player will enable you to take full advantage of your dual-room listening possibilities. |
Doubled digital/analog connections for recording
Beyond the dual-room/dual-source issue, there are other compelling reasons for hooking up your digital components with both digital and analog connections. These chiefly revolve around the use of various types of recording gear — cassette decks, DVD recorders, CD recorders, MiniDisc units, and even VCRs. Especially if you use more than one of these types of components, a doubled connection can free up many recording possibilities and ease a lot of potential headaches.
The crux of the problem with using only digital or only analog connections in recording situations can be boiled down to two simple facts:
A doubled digital/analog connection may solve other problems as well. A fair number of people are forced to hook up digital recorders such as CD-R and MD decks using their receivers' analog "record out" jacks, since many receivers don't have any digital outputs. In such cases, routing the signal from a source component through your receiver to your recording gear will only be possible if the source component is plugged into one of your receiver's analog inputs.
If your receiver does have digital outputs, you'll definitely want to use one of them to make a direct digital connection to your CD-R or MD deck, since this will enable cleaner recordings from external digital sources. But you'll want to maintain an analog "record out" connection from your receiver to your digital recording gear, too, if you have any intention of recording from analog sources such as LP, cassette, AM/FM radio, or VHS.
Beyond the dual-room/dual-source issue, there are other compelling reasons for hooking up your digital components with both digital and analog connections. These chiefly revolve around the use of various types of recording gear — cassette decks, DVD recorders, CD recorders, MiniDisc units, and even VCRs. Especially if you use more than one of these types of components, a doubled connection can free up many recording possibilities and ease a lot of potential headaches.
The crux of the problem with using only digital or only analog connections in recording situations can be boiled down to two simple facts:
- If you send a signal to your receiver through a digital input, you'll only be able to send it out to other components via a digital connection.
- Likewise, if you send a signal to your receiver through an analog input, you'll only be able to send it out to other gear using an analog connection.
 Doubled digital/analog connections between your digital components and your receiver allow you to send any audio source signal, digital or analog, to any type of recording gear you've got, digital or analog. |
A doubled digital/analog connection may solve other problems as well. A fair number of people are forced to hook up digital recorders such as CD-R and MD decks using their receivers' analog "record out" jacks, since many receivers don't have any digital outputs. In such cases, routing the signal from a source component through your receiver to your recording gear will only be possible if the source component is plugged into one of your receiver's analog inputs.
If your receiver does have digital outputs, you'll definitely want to use one of them to make a direct digital connection to your CD-R or MD deck, since this will enable cleaner recordings from external digital sources. But you'll want to maintain an analog "record out" connection from your receiver to your digital recording gear, too, if you have any intention of recording from analog sources such as LP, cassette, AM/FM radio, or VHS.
Video connections
These days, most home systems include at least 3 video sources — a TV, a DVD player, and a VCR. Using your receiver to do video switching can save you some steps every time you want to change which source you're watching. As with the audio connections described above, however, there are some compatibility issues to keep in mind when planning the video connections you'll use.
The most common video connection types — composite, S-video, and component video — are all analog rather than digital connections. Nevertheless, they are not compatible with one another unless your receiver offers video conversion. Although an increasing number of brand new receivers feature at least some form of video conversion, the vast majority of receivers currently in people's homes do not.
If your receiver does not offer video conversion, the following three rules apply to all video switching you do with it:
Use different source inputs for different connection types
Most newer TVs offer multiple source inputs (labeled Video 1, Video 2, etc.), so you can keep more than one video source hooked up and ready to play. Some source inputs include an S-video jack and a composite video jacks. Although each such source input can accept either type of video connection, it cannot accept both types at the same time.
If you were to hook up both S-video and composite video cables to the same source input, almost all TVs will prioritize the S-video input, even when no signal is being transmitted through it. This means that you'd never be able to view signals coming in through the composite video input. Therefore, if you need to make both S-video and composite video connections between your receiver and your TV, you'll need to use two separate source inputs on your TV.
Let's say your TV only has one video input and any single video component in your system only offers composite video output. Presuming your receiver does not offer video conversion, you'll have no choice but to hook up all your video components via composite video connections, and send all video signals from your receiver to your TV's composite video input.
These days, most home systems include at least 3 video sources — a TV, a DVD player, and a VCR. Using your receiver to do video switching can save you some steps every time you want to change which source you're watching. As with the audio connections described above, however, there are some compatibility issues to keep in mind when planning the video connections you'll use.
The most common video connection types — composite, S-video, and component video — are all analog rather than digital connections. Nevertheless, they are not compatible with one another unless your receiver offers video conversion. Although an increasing number of brand new receivers feature at least some form of video conversion, the vast majority of receivers currently in people's homes do not.
If your receiver does not offer video conversion, the following three rules apply to all video switching you do with it:
- Signals input to your receiver's composite video jacks can only be passed to a TV or video recorder via a composite video output.
- Signals received via an S-video input must be passed using an S-video output.
- Signals sent to your receiver's component video inputs can only be sent out through its component video outputs.
Use different source inputs for different connection types
Most newer TVs offer multiple source inputs (labeled Video 1, Video 2, etc.), so you can keep more than one video source hooked up and ready to play. Some source inputs include an S-video jack and a composite video jacks. Although each such source input can accept either type of video connection, it cannot accept both types at the same time.
 This photo shows two video inputs — each offers (from left to right) analog stereo audio jacks, a composite video jack, and an S-video jack. You should use each video input for either an S-video or a composite video connection — not both at the same time. |
If you were to hook up both S-video and composite video cables to the same source input, almost all TVs will prioritize the S-video input, even when no signal is being transmitted through it. This means that you'd never be able to view signals coming in through the composite video input. Therefore, if you need to make both S-video and composite video connections between your receiver and your TV, you'll need to use two separate source inputs on your TV.
Let's say your TV only has one video input and any single video component in your system only offers composite video output. Presuming your receiver does not offer video conversion, you'll have no choice but to hook up all your video components via composite video connections, and send all video signals from your receiver to your TV's composite video input.
Component video switching
A TV's component video inputs never share a source input with S-video or composite video inputs. This means that the dual-connection problem described above never occurs with a TV's component video inputs. One problem that can arise, however, is caused by the limited component video bandwidth of some receivers.
How much bandwidth you need to pass a component video signal depends on what video source you are using. Any receiver with component video switching will be able to pass the 480-line interlaced output of a DVD player or an HDTV tuner without picture degradation. To pass a progressive-scan DVD signal accurately, however, a receiver needs component video bandwidth of at least 12 MHz. The most demanding video source is a progressive HDTV signal, which requires approximately 30 MHz of bandwidth for flawless transfer.
If you pass a component video signal through a receiver without enough bandwidth for that signal, the result is picture degradation. If you are drastically short of bandwidth, this will be immediately apparent in glaring distortions of your video picture. If you are only a few MHz shy of the appropriate bandwidth for the signal you're viewing, the effects will be much more subtle — most commonly a slight softening of picture detail. This minor picture degradation is most noticeable on televisions larger than 36"; with smaller TVs, the difference may be unnoticeable to the naked eye.
Note: If your TV has component video inputs, but is not an HDTV-ready model, it will very likely only be able to display standard 480i (480-line interlaced) video signals. If this is the case, you'll have to set your DVD player and/or your HDTV tuner for 480i output, and any receiver with component video switching will have enough bandwidth to pass these signals. (The exceptions to this rule are a small number of flat-panel "EDTVs", which are capable of displaying a progressive-scan signal, but not HDTV signals.)
Testing for component video bandwidth
You may have trouble determining the component video bandwidth of your receiver — until very recently, manufacturers rarely made this information available, even in the owner's manuals. Nevertheless, all you need to do to figure out whether you've got enough for a particular video source is to pass its component video signal through your receiver to your TV and then look at the resulting picture.
Next, bypass your receiver and connect the video source's component video outputs directly to your TV's component video inputs. If there is an obvious improvement in the picture when you make this direct connection, your receiver definitely doesn't have enough component video bandwidth for the source in question. If the difference is not noticeable, then your receiver's component video bandwidth is sufficient.
Bypassing limited component video bandwidth
What can you do if you don't have enough bandwidth? Virtually all progressive-scan DVD players and many HDTV tuners let you switch their component video output to an interlaced signal that is not bandwidth-intensive. Another option is to connect either or both components to your receiver via S-video or composite video connections.
If you're intent on maintaining the best possible picture quality, a third option is to make direct component video connections between your high-resolution video gear and your TV. (You'll still want to send the audio signal from these components to your receiver, however, in order to hear the sound through your home theater speakers.) If you've got only one component video input on your TV, plus a progressive-scan DVD player and an HDTV tuner, then you'll have to send at least one source to your TV via a composite or S-video connection.
A TV's component video inputs never share a source input with S-video or composite video inputs. This means that the dual-connection problem described above never occurs with a TV's component video inputs. One problem that can arise, however, is caused by the limited component video bandwidth of some receivers.
How much bandwidth you need to pass a component video signal depends on what video source you are using. Any receiver with component video switching will be able to pass the 480-line interlaced output of a DVD player or an HDTV tuner without picture degradation. To pass a progressive-scan DVD signal accurately, however, a receiver needs component video bandwidth of at least 12 MHz. The most demanding video source is a progressive HDTV signal, which requires approximately 30 MHz of bandwidth for flawless transfer.
 High-resolution video signals require more component video bandwidth than some receivers offer. The diagram above illustrates how much bandwidth you'll need for two of the most popular high-res video sources. |
If you pass a component video signal through a receiver without enough bandwidth for that signal, the result is picture degradation. If you are drastically short of bandwidth, this will be immediately apparent in glaring distortions of your video picture. If you are only a few MHz shy of the appropriate bandwidth for the signal you're viewing, the effects will be much more subtle — most commonly a slight softening of picture detail. This minor picture degradation is most noticeable on televisions larger than 36"; with smaller TVs, the difference may be unnoticeable to the naked eye.
Note: If your TV has component video inputs, but is not an HDTV-ready model, it will very likely only be able to display standard 480i (480-line interlaced) video signals. If this is the case, you'll have to set your DVD player and/or your HDTV tuner for 480i output, and any receiver with component video switching will have enough bandwidth to pass these signals. (The exceptions to this rule are a small number of flat-panel "EDTVs", which are capable of displaying a progressive-scan signal, but not HDTV signals.)
Testing for component video bandwidth
You may have trouble determining the component video bandwidth of your receiver — until very recently, manufacturers rarely made this information available, even in the owner's manuals. Nevertheless, all you need to do to figure out whether you've got enough for a particular video source is to pass its component video signal through your receiver to your TV and then look at the resulting picture.
Next, bypass your receiver and connect the video source's component video outputs directly to your TV's component video inputs. If there is an obvious improvement in the picture when you make this direct connection, your receiver definitely doesn't have enough component video bandwidth for the source in question. If the difference is not noticeable, then your receiver's component video bandwidth is sufficient.
Bypassing limited component video bandwidth
What can you do if you don't have enough bandwidth? Virtually all progressive-scan DVD players and many HDTV tuners let you switch their component video output to an interlaced signal that is not bandwidth-intensive. Another option is to connect either or both components to your receiver via S-video or composite video connections.
If you're intent on maintaining the best possible picture quality, a third option is to make direct component video connections between your high-resolution video gear and your TV. (You'll still want to send the audio signal from these components to your receiver, however, in order to hear the sound through your home theater speakers.) If you've got only one component video input on your TV, plus a progressive-scan DVD player and an HDTV tuner, then you'll have to send at least one source to your TV via a composite or S-video connection.
Keeping things simple
If there are a number of people in your home that will be using your A/V system, you'll probably find that doubled video connections provide easier system operation for younger children and adult technophobes. This involves connecting your high-resolution video sources to your receiver with component and composite video inputs, or S-video and composite video inputs. The composite video connection between your TV and your receiver should be made using the input labeled Video 1 on your TV.
This setup gives you the best of both worlds. The sophisticated system user can switch between source inputs on the TV for the best possible picture with each source component. And, presuming you've got all of your video sources routed through your receiver, less experienced users will be able to switch freely between sources using only your receiver's remote, without ever having to worry about changing source inputs on your TV. The picture quality obviously won't be optimized for every source, but this setup keeps things much easier for the novice.
If there are a number of people in your home that will be using your A/V system, you'll probably find that doubled video connections provide easier system operation for younger children and adult technophobes. This involves connecting your high-resolution video sources to your receiver with component and composite video inputs, or S-video and composite video inputs. The composite video connection between your TV and your receiver should be made using the input labeled Video 1 on your TV.
This setup gives you the best of both worlds. The sophisticated system user can switch between source inputs on the TV for the best possible picture with each source component. And, presuming you've got all of your video sources routed through your receiver, less experienced users will be able to switch freely between sources using only your receiver's remote, without ever having to worry about changing source inputs on your TV. The picture quality obviously won't be optimized for every source, but this setup keeps things much easier for the novice.
 Comic appears courtesy of Penny-Arcade. |