Left and Right, the left and right front speakers, DUH
	Center, the center speaker used for dialog and effects Normal: Removes the low bass (frequencies below 100 Hz) from the center channel and redistributes them to the left and right front speakers.  This permits a smaller center speaker requiring less power than the two front speakers. Phantom: For those systems without an actual center speaker. This mode redistributes all center channel information to the two front speakers. Only those viewers seated in the center of the sound field will be able to fully appreciate the center channel. Wide: This is the best of the lot. Used when you have a center speaker about equal to the characteristics of the two main front speakers. This center speaker must be able to reproduce the full range of sound and should have the same power output of the front speakers.
	Surround: The rear speakers. In all formats but true six channel audio like Dolby 5.1 (AC-3) or DTS this is actually a monophonic arrangement. Since no room is truly symmetrical there will be differences heard by the viewer. The combined output needs to be only about half of the front speakers. For six channel set ups each of the two rear speakers will receive its own independent signal.
	Sub Woofer this is a special speaker that reproduces only the very low frequencies. For full 5.1 setups the signal comes from the special .1 track directly to the sub woofer. For all other modes the information that goes to the sub is controlled by the cross over frequency. This setting determines which frequencies goes to the sub woofer. Sub woofers come in two varieties, passive and powered. The passive sub is like the rest of your speakers, it is driven by your amplifier or receiver. The powered sub woofer has its own independent amplifier. This type will also required a separate power cord as well as the wires to the receiver.
	Rear Center: With the new 6.1 formats this works much like the front center but provides a greater feel of a full surround field in the rear. Since only a few receivers have this option and only a handful of DVDs are encoded in it, don't worry about it yet.

All speakers located less than about two feet from your TV or VCR should be shielded. This means that the magnets in the speakers are shielded from the outside. Most AV speakers used as front or center speakers are shielded. This is very important for the center speaker which commonly sits on top of the TV. If a speaker is close to your collection of video tapes or computer disks it also has to be shielded.