You may already know what kind of video display will best fit your needs and your home theater space. You may know some of the things to look for in a surround-sound audio system. But what about all those home theater components that are going to be in a closet, rack or cabinet? At some point in the process of planning your home theater, you’ll either be handed an equipment list or you’ll make your own shopping list. If you’re an audio/video aficionado, this could be a moment of great joy. But if you’re like most of us, it is a moment of confusion and dread. Don’t panic. Here’s a rundown of some of the more popular components you’re likely to encounter, what they do and what to look for in each one.

DVD/CD and Universal Disc Players
Both the video and the audio from a movie or concert in a home theater starts right here.  The DVD is the staple component in any audio/video system, as it’s capable of playing both DVDs and audio CDs, making it two components in one. DVD players range from the ridiculously inexpensive for a basic unit to $1,000 or more for high-end universal disc players that are compatible with newer multichannel DVD-Audio (DVD-A), Super Audio CD (SACD) and just about any other flavor of disc you can find. Oh yes: They also play DVDs.

Some DVD players are single-disc models; others hold several discs in a tray carousel so you don’t have to keep changing them. This is especially good for playing a succession of your favorite CDs.

Look for:

• The ability to play multiple formats such as CD-R, CD-RW, DVD-R and others.
• Progressive scanning for the best DVD picture quality, if you plan on having a digital TV or a high-definition TV.
• Component or S-Video connections for better video quality.
• Optical audio outputs for better sound quality.

Extras:

• High-definition multimedia interface (HDMI) or digital visual interface (DVI) outputs for the best video quality on an HDTV.
• Higher-end units may scale DVD video to high-definition quality.
• Optical audio connections for DVD-A and SACD players.

Digital Video Recorders
Digital Video Recorders (DVRs) are also known as personal video recorders (PVRs) or by the brands TiVo and ReplayTV. These devices enable you to record shows to a hard drive, like one you might find on a computer, by simply pointing and clicking on a show through an on-screen programming guide. This makes them much easier to operate than VCRs. And now they are being built into cable boxes, satellite receivers, TVs, DVD recorders, TVs, you name it. You also still have the option of buying a separate box.

DVRs from TiVo and ReplayTV require payment to a monthly subscription service to keep the onscreen programming guide updated, but the devices come with many features. Some DVRs can be used with modules in other rooms to send a recorded program from one TV to another. And newer units can even record in high-definition video.

Look for:

• Large hard-drive storage if you plan to record a lot of shows.
• S-Video connections at a minimum (some don’t have component video).
• Optical audio connections for better sound quality.
• Broadband or network connection capability.

Extras:

• The ability to pull photos and music from your PC.

Audio/Video Receivers
Audio/video receivers, surround-sound receivers, and integrated amplifiers do a lot of things and are perfect for family room arrangements and modest media room setups. These components bring in audio and video from your DVD player, VCR and other devices and send the audio to the speakers and the video to your TV or display. They process your audio for surround sound, amplify it with built-in amplifiers and power each speaker in your home theater setup. They are the brains of your entire home theater system, in one box.

The only difference between integrated amplifiers and receivers is that receivers have radio tuners, usually AM and FM.

Look for:

• Dolby Digital and digital theater systems (DTS) capabilities for at least five channels plus a subwoofer.
• Ample inputs and outputs for other components.
• Component video outputs for better picture quality.
• Optical audio inputs for better sound quality.
• Plenty of presets for radio stations.
• Subwoofer output.

Extras:

• THX certification for the best audio quality.
• Dolby Digital EX, THX Surround EX, Dolby Pro Logic IIx or some iteration of DTS-ES for six- and seven-channel setups.
• HDMI connection that carries both audio and video signals.

Preamplifiers and Controllers
Want a more robust home theater system? Then you may want a surround-sound controller that’s separate from a radio tuner and amplifier. These are sometimes referred to as audio/video (A/V) controllers or decoders, or surround-sound processors or decoders. No matter what they’re called, they all do basically the same things: prepare the audio signal for amplification before it reaches a separate amplifier or amplifiers and prepare the video signal for the TV or display. And because it does only these things, it tends to do them better than controllers with built-in amplifiers or radio tuners. These devices are typically used in high-end home theaters such as those in dedicated theater rooms or those built for audio enthusiasts.

Look for:

• Dolby Digital EX, THX Surround EX, Dolby Pro Logic IIx or some iteration of DTS-ES.
• Ample inputs and outputs for other components.
• Component video outputs for better picture quality.
• Optical audio inputs for better sound quality.
• Plenty of presets for radio stations.
• Subwoofer output.

Extras:

• THX certification for the best audio quality.
• HDMI connection that carries both audio and video signals.
• Ethernet IP network connections.

Amplifiers
If you’re interested in serious audio fidelity, and you want to turn up the juice, a separate amplifier or multiple amplifiers will do the trick. These are the components that send power to the speakers. They are often used in larger home theaters and media rooms to deliver a cleaner and stronger signal to the loudspeakers.

Most amplifiers power two or more speakers from the same chassis. An amplifier can provide power for two channels for a stereo setup or five or more channels for surround sound. Some home theater arrangements include two or more amplifiers. Subwoofers are sometimes powered separately because of the amount of power they require to deliver big booms and low bass. Monoblock amplifiers power only one channel each and are used mostly in serious audio enthusiasts’ systems.

Look for:

• Power and impedance ratings that match your speakers.
• Good, sturdy build quality.
• Clean sound that is free of distortion.
• Heat dissipation, as amps can get hot.

Extras:

• If you’re going to spend more for a separate power amplifier, get one that’s THX certified for the best movie sound reproduction.

Digital Broadcast Systems
These systems take a signal from a small satellite dish and feed it to a satellite receiver and then onto your TV and audio system. One major flaw in digital satellite has been a lack of local broadcast channels, but that is changing. Definitely check on this issue if you want to see local broadcast channels through a satellite system. You’ll also want to compare subscription rates, the number of channels available and whether the dish needs to be moved to receive certain channels.

Some systems have two tuners so you can watch different programs in different rooms, while others come packaged with DVR technology so you can record programs to a hard disk and watch them later. Satellite is also a good way to get HDTV programming, but be sure you buy an HDTV-capable satellite receiver and have an HDTV-compatible or HD-ready monitor as well.

Look for:

• As many audio/video connections as possible.
• Component or S-Video connections.
• Parental controls.

Extras:

• DVR functions.
• HDTV tuners.
• Receivers with high-definition DVR recorders.

Video Cassette Recorders
Yes, VCRs still exist, and you may still want one if you have a collection of VHS tapes and don’t want to repurchase everything on DVD. Your VCR hooks up to the audio/video receiver or controller via RCA-type jacks for audio. If you just want a VCR so the kids can play their favorite tapes, you can get a relatively inexpensive one.

Look for:

• Quality build and durability.
• Ease of use and programming.
• Automatic rewind at the end of a tape.
• Automatic clock set.
• Commercial skip feature.
• Front jacks for plugging in a camcorder.

Extras:

• If you must buy a VCR, and you want quality, pay a few extra bucks, and get a four-head hi-fi stereo or S-VHS unit.
• DVD-VCR combo decks are a good way to enjoy both DVDs and VHS tapes.

Digital VHS
Can’t wait for high-definition DVD recorders to make copies of your favorite shows? Then you may want a D-VHS (digital VHS) player and recorder. The device is just like a VCR, only it can record and play high-definition tapes. The downside is that it’s still tape. But at least it’s high-def.

Look for:

• Ability to play D-VHS, S-VHS and standard VHS tapes.
• Ability to support different HDTV display resolutions.
• FireWire (IEEE 1394 connections) so you can record.

Extras:

• Be sure the HDTV receiver has FireWire (IEEE 1394 connections) as well.

Steven Castle - Contributing Writer

Steven Castle is Electronic House's managing editor. he has been writing about consumer electronics, homes and energy efficiency topics for two decades. He is also the co-founder of GreenTech Advocates.