Denon 685 Operating Instructions Manual page 60

ENGLISH
Surround
The AVR-1705/685 is equipped with a digital signal processing circuit that lets you play program sources in the surround mode to achieve the same
sense of presence as in a movie theater.
Dolby Surround
(1) Dolby Digital
Dolby Digital is the multi-channel digital signal format developed by Dolby Laboratories.
Dolby Digital consists of up to "5.1" channels - front left, front right, center, surround left, surround right, and an additional channel exclusively
reserved for additional deep bass sound effects (the Low Frequency Effects – LFE – channel, also called the ".1" channel, containing bass
frequencies of up to 120 Hz).
Unlike the analog Dolby Pro Logic format, Dolby Digital's main channels can all contain full range sound information, from the lowest bass, up
to the highest frequencies – 22 kHz. The signals within each channel are distinct from the others, allowing pinpoint sound imaging, and Dolby
Digital offers tremendous dynamic range from the most powerful sound effects to the quietest, softest sounds, free from noise and distortion.
Dolby Digital and Dolby Pro Logic
2
Comparison of home surround systems
No. recorded channels (elements)
No. playback channels
Playback channels (max.)
Audio processing
High frequency playback limit of surround
channel
Dolby Digital compatible media and playback methods
2
Marks indicating Dolby Digital compatibility:
The following are general examples. Also refer to the player's operating instructions.
Media
LD (VDP)
DVD
Others
(satellite broadcasts, CATV, etc.)
1 Please use a commercially available adapter when connecting the Dolby Digital RF 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-1705/685, 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-1705/685.
(2) Dolby Pro Logic II x
II
• Dolby Pro Logic
up to 6.1 playback channels, including the surround back channel. Dolby Pro Logic
6.1 channels.
The mode can be selected according to the source. The Music mode is best suited for playing music, the Cinema mode for playing movies,
and the Game mode for playing games. The Game mode can only be used with 2-channel audio sources.
60
Digital discrete processing
Dolby Digital encoding/decoding
Coaxial Dolby Digital RF output jack
Optical or coaxial digital output
Optical or coaxial digital output
x furthers the matrix decoding technology of Dolby Pro Logic
Dolby Digital
5.1 ch
5.1 ch
L, R, C, SL, SR, SW
20 kHz
.
Dolby Digital output jacks
1
(same as for PCM) 2
(same as for PCM)
II
to decode audio signals recorded on two channels into
II
Dolby Pro Logic
2 ch
4 ch
L, R, C, S (SW - recommended)
Analog matrix processing Dolby Surround
7 kHz
Playback method (reference page)
Set the input mode to "AUTO".
(Page 35)
Set the input mode to "AUTO".
(Page 35)
Set the input mode to "AUTO".
(Page 35)
x also allows 5.1-channel sources to be played in up to