(e.g., a Dolby Digital or DTS 5.1 source with Logic
7/7 or Dolby Pro Logic IIx post-processing) are allow-
able, others (e.g. A Dolby Digital 5.1 source with DTS
Neo:6) are not. If you wish to add surround back
channels to a 2.0 or 5.1 source we recommend that
you experiment with the various options to see which
may be available and which are best suited to your
taste and listening environment.
It is always a good idea to check the readout for the
channel data to make certain that it matches the audio
logo information shown on the back of a DVD pack-
age. In some cases, you will see an indication for
“2/0/0” even when the disc contains a full 5.1, or
3/2/.1, signal. When this happens, check the audio
output settings for your DVD player or the audio menu
selections for the specific disc being played to make
certain that the player is sending the correct signal
to the AVR.
PCM Playback
PCM is the abbreviation for Pulse Code Modulation,
the digital signal format used for standard CD play-
back, and other non-Dolby Digital and non-DTS digital
sources such as Mini-Disc. When a
PCM
signal is
detected, the
Lower Display Line
$
will briefly
show a message with the letters PCM, in addition to a
readout of the sampling frequency of the digital signal.
In most cases, this will be
PCM 44.1kHz
or
PCM 48kHz
, though in the case of specially
mastered, high-resolution audio discs, you will see a
PCM 96kHz
indication. Note that the sampling
rate displayed is that of the incoming digital signal, and
not the upsampled rate that may be applied to PCM
sources when Dolby Pro Logic or Pro Logic II pro-
cessing is applied, as shown on page 22.
During PCM playback you may select any surround
mode except one of the Dolby Digital or DTS/DTS-ES
modes. However, when a CD with HDCD encoding is
being played you must select the Surround Off (stereo)
mode to take advantage of the HDCD process.
HDCD Playback
High Definition Compatible Digital,
®
or HDCD, discs are
recorded using a special process that uses 20-bit
encoding and other proprietary processing to provide
the ultimate in CD listening. When an HDCD-encoded
disc is playing and the CD player is connected using a
coaxial or optical digital connection, the AVR 635 will
automatically recognize the HDCD encoding and acti-
vate the circuits required for proper playback, provided
that the Surround Off mode is selected. An
HDCD
message will appear in the
Lower Display Line
$
to confirm the HDCD playback. HDCD playback is
limited to two-channel stereo only.
Speaker/Channel Indicators
In addition to the bitstream indicators, the AVR 635
features a set of unique channel-input indicators that
tell you how many channels of digital information are
being received and/or whether the digital signal is
interrupted (Figure 21).
Figure 21
The letters inside the boxes tell you which channels
are receiving an input signal. Since conventional ana-
log audio is only two channels, the “L” and “R” letters
will light with any analog source. When a digital source
is in use you will see letters displayed that correspond
to the number of channels in the incoming data
stream, which may be just the L and R for two chan-
nel PCM or 2.0 Dolby Digital material. When a 5.1
signal is being received the L/C/R/SL/SR indicators
will light, with the LFE indication also being shown
when an LFE signal is present. All seven indicators,
including the SBL/SBR letters will light for a 7.1 sig-
nal, and a horizontal line is shown to connect the
SBL/SBR indicators when a 6.1 source is in use.
It is important to note that although Dolby Digital, for
example, is referred to as a “5.1” system, not all Dolby
Digital DVDs or programs are encoded for 5.1. Thus, it
is sometimes normal for a DVD with a Dolby Digital
soundtrack to trigger only the “L” and “R” indicators.
NOTE:
Many DVD discs are recorded with both “5.1”
and “2.0” versions of the same soundtrack. When
playing a DVD, always be certain to check the type of
material on the disc. Most discs show this information
in the form of a listing or icon on the back of the disc
jacket. When a disc does offer multiple soundtrack
choices, you may have to make some adjustments to
your DVD player (usually with the “Audio Select” button
or in a menu screen on the disc) to send a full 5.1
feed to the AVR 635. It is also possible for the type of
signal feed to change during the course of a DVD’s
playback. In some cases, the previews of special
material will only be recorded in 2.0 audio, while the
main feature is available in 5.1 audio. The AVR 635
will automatically sense changes to the bitstream and
channel count and reflect them in these indicators.
The letters used by the
Speaker/Channel Input
Indicators
@
will flash to indicate when a bitstream
has been interrupted. This will happen when a digital
input source is selected before the playback starts, or
when a digital source such as a DVD is paused. The
flashing indicators remind you that the playback has
stopped due to the absence of a digital signal and not
through any fault of the AVR 635. This is normal, and
the digital playback will resume once the playback is
started again.
The boxes around the channel indication letters are
used to show which speakers are configured in your
system. A small box around the letter indicates that a
“Small” speaker has been assigned to that position,
while a larger, double box indicates a “Large” speaker
assignment.
Note that in some cases, such as an analog stereo or
2.0 digital source you will see empty speaker position
boxes, which indicates that the speaker is active and
will receiver sound, but that there is no discrete signal
for that channel. In other cases you may see letters
with no speaker boxes. This indicates that there is a
discrete signal for that channel, but due to the mode
in use (e.g. Dolby VS with a 5.1 source) there is no
signal being sent to the channel.
Night Mode
A special feature of Dolby Digital is the Night mode,
which enables specially encoded Dolby Digital input
sources to be played back with full digital intelligibility
while reducing the minimum peak level by 1/4 to 1/3.
This prevents abruptly loud transitions from disturbing
others, without reducing the impact of the digital
source. The Night mode is available only when Dolby
Digital signals with special data are being played.
The Night mode may be engaged when a Dolby
Digital DVD is playing by pressing the
Night Mode
Button
T
on the remote. Next, press the
⁄
/
¤
Navigation Button
o
to select either the middle
range or full compression versions of the Night
mode. To turn the Night mode off, press the
⁄
/
¤
Navigation Button
o
until the message in the
lower third of the video display and in the
Lower
Display Line
$
reads
D-RANGE OFF
.
The Night mode may also be selected to always be on
at either level of compression using the options in the
DOLBY SURR
menu. See page 22 for informa-
tion on using the menus to set this option.
MP3 Audio Playback
The AVR 635 is one of the few receivers equipped for
onboard decoding for the MP3 audio format used by
computers and portable audio devices. By offering
MP3 decoding, the AVR 635 is able to deliver precise
conversion of the digital signals to an analog output,
along with the benefits of listening to the MP3 audio
through the AVR 635’s high-current amplifier and the
speakers from your surround system, rather than the
smaller speakers and low-powered amplifiers typically
used with computers.
OPERATION
36
OPERATION
AVR 635 OM 12/2/04 3:28 PM Page 36
