Sony SLV-AV100UX Taking advantage of the sound fields, What’s surround sound?

Taking advantage of the sound fields (continued)

What’s Dolby Surround and Dolby Pro Logic Surround?

Dolby Surround is a system that decodes the extra channels of Dolby Surround encoded sound tracks on movie videos and TV programmes, and produces sound effects and echoes that make the action seem to envelop you.

Dolby Pro Logic Surround is a more advanced system developed after Dolby Surround. The sound image is improved by using four separate channels: off-screen audio effects, on-screen dialogue, left-to-right panning, and music. These channels manipulate the sound and enhance the action as it happens on the screen.

The unit offers PROLOGIC mode for these systems as one of the sound fields. You can tell if a video tape or laser disc uses Dolby Surround or Dolby Pro Logic Surround encoded software by looking at the packaging. (Some video tapes and laser discs may use Dolby Surround even if it’s not indicated on the package.)

What’s surround sound?

Surround sound consists of three elements, direct sound, early reflected sound (early reflections), and reverberated sound (reverberation). The acoustics of the venue affect the way these three sound elements are heard.

The unit combines the three sound elements in such a way that you can actually feel the size and type of a particular venue such as a concert hall. The unit also varies the combination of the sound elements to offer you a variety of sound fields (THEATRE, MONO MOVIE, HALL, STADIUM, and GAME).

The three sound elements in an actual concert hall

Early reflections Reverberation

Direct sound

Transition of sound from rear speakers

Direct sound

	Early
Level	reflections Reverberation

Early reflections time Time

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Sound Field Operations