Digital Audio Playback - Harman Kardon AVR 745 Owner's Manual

OPERATION
press the Screen Button 6 to the right of Surr
Menu. The options list will change again, this time
showing the major display category modes. The first
press of a button will show the current mode from that
group if it is already in use, or the first available mode
if you are currently using another mode. To cycle
through the available modes in that group, press the
button again until the desired mode appears in the
Lower Display Line $, the on-screen display and
the front-panel Surround Mode Indicators %.
The Dolby Digital, Dolby Digital EX, DTS 5.1, DTS-ES
Matrix and DTS-ES Discrete modes may only be
selected when a digital input is in use. In addition,
when a digital source is present, the AVR 745 will
automatically select and switch to the correct mode,
regardless of the mode that has been previously
selected. For more information on selecting digital
sources, see the Digital Audio Playback section below.
When the 6-channel/8-channel direct inputs are in
use, there is no surround processing, as these inputs
take the analog output signals from an external source
device and carry them straight through to the volume
control without any further digital processing.
To listen to a program in traditional two-channel
stereo, using the front left and front right speakers
only (plus the subwoofers, if installed and configured),
first follow the instructions shown above so that the
AVR: Surround Menu page of the
TC 30 remote is on the LCD Screen 7, and then
press the Screen Button 6 to the right of the
Stereo option until SURROUND OFF appears
in the Lower Display Line $. From the front panel,
press the Surround Mode Group Selector 2 until
the Stereo modes appear in the on-screen display
and Lower Display Line $. Next, press the
Surround Mode Selector Button 3 until
SURROUND OFF appears in the on-screen
display and Lower Display Line $.

Digital Audio Playback

Digital audio is a major advancement over older analog
surround processing systems. It delivers up to six dis-
crete channels, and each channel reproduces a full-fre-
quency range (20Hz to 20kHz) and offers dramatically
improved dynamic range and significant improvements to
signal-to-noise ratios. In addition, digital systems have the
capability to deliver an additional channel that is specifi-
cally devoted to low-frequency information. This is the
".1" channel referred to when you see these systems
described as "5.1, " "6.1" or "7.1." The bass channel is
separate from the other channels, but since it is inten-
tionally bandwidth-limited, sound designers have given
it that unique designation. When a digital soundtrack
is playing, the number of channels available will
vary according to the way in which the program was
recorded. Although most movies recorded with digital
42 OPERATION
sound have 5.1 soundtracks, some have 6.1 or 7.1
sound, while others retain the original two-channel or
even monaural sound. When the program source is a
broadcast, cable or satellite delivered digital program,
only one type of soundtrack may be delivered at a
time, while optical sources such as DVD may provide
more than one audio option. In either case, the deci-
sion of what type of sound track and how many chan-
nels to offer is up to the program's producer. With the
AVR 745 you are able to not only play back the origi-
nal compatible digital format, but using the processing
power of the Texas Instruments DSP processor, it is
possible to decode the basic digital track for 2.0 or
5.1 sound and then select an additional "post-pro-
cessing" mode to deliver additional channels.
Dolby Digital
Dolby Digital is the default format for DVD discs and
for the (ATSC) high-definition system used in the
United States and Canada. It is also used by the digital
satellite program services and is available on most
digital cable set-top boxes. When the AVR 745 is con-
nected to a blue-laser-based high-definition optical
disc player via an HDMI, coaxial or optical digital con-
nection, the soundtrack from the player is also avail-
able in the standard Dolby Digital format so that it may
be decoded by the AVR.
An optional, external RF demodulator is required to
use the AVR 745 to listen to the Dolby Digital sound-
tracks available on laser discs. Connect the RF output
of the LD player to the demodulator and then connect
the digital output of the demodulator to the Optical
or Coaxial Inputs KM
of the AVR 745. A
demodulator is not required for use with high-definition
optical disc or DVD players, or with DTS-encoded
laser discs.
In order to provide maximum playback compatibility
with DVDs, the AVR 745 receiver will always default
first to the playback mode embedded in a disc's digital
"flag" information. For Dolby Digital discs, the following
playback modes are initially selected after the AVR
locks to the incoming digital audio data stream to
identify the selected:
• When a Dolby Digital 5.1 data stream is detected,
the choice of which surround mode is activated is
determined by the setting on the DEFAULT
SURR line of the SURROUND CONFIG
menu (Figure 19), as shown on page 28.
• When a disc with the Dolby Digital EX format flag is
played, your system will automatically switch to the
EX mode when seven main-channel speakers are
available.
• When a disc with 2.0 Dolby Digital data is detected,
the default mode is Dolby Digital with Pro Logic II
postprocessing when you have a 5.1 speaker sys-
tem, or Dolby Digital with Pro Logic IIx postprocess-
ing when you have a 7.1 speaker system.
• Depending on the number of speaker channels
available in your system, once the AVR locks to
the digital signal, you may select any surround
mode or postprocessing option that is available,
based on the incoming data stream's possible
restrictions and the number of speakers in your
system. For example, when a 5.1 or 2.0 audio
stream is in use, you may select alternate post-
processing such as Logic 7/7-channel Movie Mode
postprocessing to create the rear surrounds in 7.1
speaker systems.
DTS
DTS is another digital audio system that is capable
of delivering 5.1 or 6.1 discrete or matrix sound field
reproduction. Although both DTS and Dolby Digital are
digital, they use different methods of encoding the sig-
nals, and thus they require different decoding circuits
to convert the digital signals back to analog.
DTS-encoded soundtracks are available on select DVD
and LD discs, as well as on special audio-only DTS
discs. You may use any LD or CD player equipped
with a digital output to play DTS-encoded discs with
the AVR 745. All that is required is to connect the
player's output to either an Optical or Coaxial Input
or front panel KM.
on the rear panel
In order to listen to DVDs encoded with DTS sound-
tracks, the DVD player must be compatible with the
DTS signal, which is indicated by a DTS logo on the
player's front panel. Early DVD players may not be
able to play DTS-encoded DVDs. If you are in doubt
as to the capability of your DVD player to handle DTS
discs, consult the player's owner's manual.
When the AVR 745 is connected to a blue-laser-
based high-definition optical disc player via an HDMI,
coaxial or optical digital connection, the soundtrack
from the player is also available in the standard DTS
format so that it may be decoded by the AVR.
NOTE:
• Some DVD players have a default setting that does
not pass through the DTS signal. Before playing
DVDs with a DTS soundtrack, make certain that
the settings in your DVD player have been properly
adjusted so that DTS audio is passed through.
Consult the owner's manual for your DVD player for
more information on making these settings.
• When selecting surround modes, any mode where
the setting in its mode group (Dolby, DTS, Logic 7,
PCM, etc.) has been set to OFF in one of the
SURROUND CONFIG menus will not
appear. You may change the settings in this list at
any time by following the instructions on page 28.