NAIM AV2 Owner's Manual page 19

Decode
Mode
Direct
Mono
Stereo
Dolby PL II
Music
Dolby PL II
Movie
Dolby Digital
Surround EX
DTS Neo:6
Cinema
DTS Neo:6
Music
DTS Neo:6
Auto
18
10.0 av2 operation
10.5
Maximum Speaker Channels
Left Front Centre Right Front
10.6
decode modes and channel schemes
Left Surround Right Surround
surround encoding background and technology
Feature films have carried the multi-channel sound tracks necessary for "surround
sound" in some cases since the 1950s. But only since the mid 80's have the benefits of
surround sound been available to domestic "home theatre" consumers. The technology
that first enabled four channels of audio to be decoded from the stereo soundtrack of
consumer media such as video cassette is Dolby Surround Pro Logic. Since Dolby
Surround Pro Logic, and especially following the introduction of digital audio-visual
products such as DVD, enhanced encode and decode technologies have been introduced
that enable a greater number of higher quality channels of audio to be encoded. With
digital encoding techniques such as Dolby Digital and DTS Surround, appropriately
encoded feature films, music and even computer games can be reproduced in full-
bandwidth surround sound with up to seven audio channels (left, right, centre, surround
left, surround right, surround extra, low-frequency effects).
The following few paragraphs provide a short description and explanation of each
decode technology and mode available on the av2. Further technical information can be
found at www.dolby.com and www.dtsonline.com
Dolby Surround Pro Logic
Dolby Surround Pro Logic is a matrix decoding process that generates four output
signals (left, right, centre, surround) from a Dolby Surround encoded analog stereo input
signal. It is built into virtually every home theatre audio system. The nature of Pro Logic
decoding constrains the single surround channel to relatively narrow bandwidth.
Dolby Surround Pro Logic II
Dolby Surround Pro Logic II is an improved analog matrix decoding technology that
provides improved surround performance on Dolby Surround encoded program material.
While earlier surround programme material is fully compatible with Pro Logic II,
appropriately encoded soundtracks can take full advantage of its enhancements - which
include separate full bandwidth left and right surround channels. Pro Logic II also
features two distinct decoding options for "music" and "movie" programme material.
Extra Rear Sub-Woofer