Recently I brought a home theater system with 'Pro Logic surround', it work well with my LD player. But, I don't hear the same effect with my vcd player. Can vcd produce surround sound ?

-- cy (cyang-ams@uhls.com.sg), August 31, 1999

Answers

Video CDs if original copyrighted versions do have Dolby Surround. It is not Dolby ProLogic. It is regular Dolby Surround similar to VHS tapes. So far the latest releases from the studios are Dolby Surround. One movie in particular The Long Kiss Goodnight Malaysian Version is in Dolby Digital 2.0 surround. For those who will say Dolby Digital can only be or has to be 5.1, WRONG! Dolby Digital can carry up to 5.1 channels of audio. For example a two speaker stereo will downplay the DD 5.1 to DD Stereo or only four channels(speakers) makes DD 2.0 surround. The Video CD player itself must support Dolby Surround. My laptop can playback Dolby Surround channels very well. For a test of your player you can buy Sudden Death(Hong Kong version) which has the Dolby Surround logo on the back. It is available from www.cdmovies.com. Almost all of my legal version movies have Dolby Surround encoded into the tracks.

-- The Lone Ranger (rutger_s@hotmail.com), August 31, 1999.

Addition to my answer from Dolby labs themselves:

Basic Dolby Surround decoders feature:

Passive matrix decoding to derive the surround channel. Three output channels: left, right, and surround. Surround channel processing: frequency response limited to 7 kHz plus modified Dolby B-type noise reduction. Surround channel time delay: fixed at 20 milliseconds (thousands of a second, or ms), or variable from 15 ms to 30 ms. Manual input balance control. Level adjustment to match surround channel volume to front channels. Master volume control of all output channels.

Dolby Surround Pro Logic decoders feature in addition: High-separation, active matrix decoding for enhanced directionality. Four output channels: left, center, right, surround. Automatic input balance control (most units). Test noise sequencer and level adjustments to balance all four channels. Center channel mode control: Normal, Phantom, and optional Wide modes

That is why you do not feel the surround as much. Normal Dolby Surround was optimized for four channel output not five like on ProLogic systems.

-- The Lone Ranger (rutger_s@hotmail.com), September 02, 1999.