Surround Decoding!

Have you ever wanted to know what all the surround sound formats meant when talking with an Audio Salesman? Well we are here to clarify it for you. The surround sound formats supported by the A/V system will affect the realism and intensity of the experience.

Dolby Pro Logic: base level surround decoding that will work with essentially any source.Generates front left and right, center, and surround outputs (with the mono surround output normally reproduced through two speakers). Works well only with Dolby Surround encoded soundtracks. This or Dolby Pro Logic II is an essential feature.

Dolby Pro Logic II: an advanced version of Dolby Pro Logic. It provides superior surround decoding with stereo surround output. Also works very well for generating five channel surround from two channel stereo music recordings, such as CDs. Highly desirable. If you could have only one surround decoding option, this would be the one for you to choose.

Dolby Pro Logic IIx: enhanced version of DPL II that can deliver up to 7.1-channel output. Nice if you can put one or two back surround speakers in the room in addition to the standard left and right surrounds, but would be useless otherwise.

Dolby Digital: Dolby Digital decoding is the best choice for multichannel Dolby Digital soundtracks delivered in that format, as they are on DVD, HDTV, and some satellite transmissions. But it's useless for things like VHS releases or analog TV programs that can't carry Dolby Digital but can deliver Dolby Surround. For those you need Dolby Pro Logic or Pro Logic II, which are, in effect, universal sound decoders. And, if you have to choose just one, choose DPL II.

Dolby Digital EX: an enhanced version of Dolby Digital that allows a back surround channel in soundtracks in addition to the usual left and right surrounds. Nice to have if you can accommodate the extra speaker or two at the back, but useless otherwise. Works well with Dolby Digital EX and some regular Dolby Digital soundtracks.

DTS: an alternative surround encoding/decoding format that is functionally equivalent to Dolby Digital. It offers no advantage, however, and is not as widely used. Not really needed except for certain special DTS encoded multichannel CDs.

A/V Reporter,
CL West