ENGLISH

2Dolby Digital and Dolby Pro Logic

Comparison of home surround systems

Dolby Digital

Dolby Pro Logic

 

 

 

No. recorded channels (elements)

5.1 ch

2 ch

 

 

 

No. playback channels

5.1 ch

4 ch

 

 

 

Playback channels (max.)

L, R, C, SL, SR, SW

L, R, C, S (SW - recommended)

 

 

 

Audio processing

Digital discrete processing

Analog matrix processing Dolby Surround

Dolby Digital (AC-3) encoding/decoding

 

 

 

 

 

High frequency playback limit of surround

20 kHz

7 kHz

channel

 

 

 

 

 

2Dolby Digital compatible media and playback methods

Marks indicating Dolby Digital compatibility: and . The following are general examples. Also refer to the player’s operating instructions.

Media

Dolby Digital output jacks

Playback method (reference page)

 

 

 

LD (VDP)

Coaxial Dolby Digital RF output jack

Set the input mode to “AUTO”.

*1

(Page 32)

 

 

Optical or coaxial digital output

Set the input mode to “AUTO”.

DVD

(same as for PCM)

(Page 32)

 

*2

 

 

Others

Optical or coaxial digital output

Set the input mode to “AUTO”.

(satellite broadcasts, CATV, etc.)

(same as for PCM)

(Page 32)

 

 

 

*1 Please use a commercially available adapter when connecting the Dolby Digital RF (AC-3RF) output jack of the LD player to the digital input jack.

Please refer to the instruction manual of the adapter when making connection.

*2 Some DVD digital outputs have the function of switching the Dolby Digital signal output method between “bit stream” and “(convert to) PCM”. When playing in Dolby Digital surround on the AVR-2801/981, switch the DVD player’s output mode to “bit stream”. In some cases players are equipped with both “bit stream + PCM” and “PCM only” digital outputs. In this case connect the “bit stream + PCM” jacks to the AVR-2801/981.

(2)Dolby Pro Logic

Dolby Pro Logic is a multi-channel signal playback system developed by Dolby Laboratories which decodes sources recorded in Dolby Surround into four channels: front left, center, front right and surround (the surround channel is monaural, but is played through two surround speakers). Here, “sources recorded in Dolby Surround” are sources on which surround signals (three channels or more) are recorded onto two channels using Dolby Surround encoding technology. Dolby Surround recording is possible for all two-channel signal sources, including

soundtracks on DVDs ( * ), LDs or hi-fi VCRs (for which stereo signal recording is possible), stereo FM, TV and satellite broadcasts, stereo CD, MD and analog cassette tape recordings. Sources recorded in Dolby Surround are compatible with stereo playback, so they can be played in stereo on regular stereo equipment and in surround with Dolby Pro Logic processing. (DTS and Dolby Digital require special decoders to be played.)

With Dolby Pro Logic, the signal levels of the different channels of the source recorded in Dolby Surround are monitored, channels with higher signal levels are emphasized and the level of the other channels is decreased in order to reinforce the directivity and achieve an effective surround sound.

*DVDs recorded in Dolby Surround include sources recorded in PCM and sources recorded in 2-channel Dolby Digital. For 2-channel Dolby Digital DVD sources, the DVD player’s audio mode is 2-channel Dolby Digital, and the AVR-2801/981’s surround mode is Dolby Pro Logic.

2Dolby Pro Logic compatible media and playback methods

Mark indicating Dolby Pro Logic compatibility:

When playing in Dolby Pro Logic, select the input signal according to how the player is connected to the AVR-2801/981, in the same way as selecting the stereo signal (see page 20). Set the surround mode to “DOLBY SURROUND” (see page 37) to play in Dolby Pro Logic.

Manufactured under license from Dolby Laboratories.

“Dolby”, “Pro Logic” and the double-D symbol are trademarks of Dolby Laboratories. Confidential Unpublished Works, ©1992-1997 Dolby Laboratories. All rights reserved.

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