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 optional, external DVD-Audio or SACD player, or another source device and carry them straight through to the volume control.
To listen to a program in traditional two-channel stereo, using the front left and front right speakers only (plus the subwoofer, if installed and configured), press the Stereo Button 5
until SURR OFF appears in the Main Information Display ˜.
Digital Audio Playback
Digital audio is a major advancement over older analog surround processing systems such as Dolby Pro Logic. It delivers five or six discrete channels: left front, center, right front, left surround and right surround and with DTS ES (see below) even surround back (with identical signals for left and right). Each channel repro- duces full frequency 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 specifically devoted to low-frequency infor- mation. 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 intentionally bandwidth-limited, sound designers have given it that unique designation.
Dolby Digital
Dolby Digital (originally known as AC-3®) is a standard part of DVD, and is available on specially encoded LD discs and satellite broadcasts and it is a part of the new high- definition television (HDTV) system.
Note that an optional, external RF demodulator is required to use the AVR 5550 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 *Ó of the AVR 5550. No demodulator is required for use with DVD players or DTS-encoded laser discs.
DTS
DTS is another digital audio system that is capa- ble of delivering 5.1, 6.1 or 7.1 audio. Although both DTS and Dolby Digital are digital, they use different methods of encoding the signals, and thus they require different decoding circuits to convert the digital signals back to analog.
DTS-encoded sound tracks are available on select DVD and LD discs, as well as on special audio- only DTS CDs. You may use any LD, DVD or CD player equipped with a digital output to play DTS-encoded special audio-only CDs with the AVR 5550, but DTS-LDs can be played on LD players and DTS-DVDs on DVD players only. All that is required is to connect the player’s digital output to either the Optical or Coaxial input on
the rear panel | or front panel *Ó. |
In order to listen to DVDs encoded with DTS sound tracks, the DVD player must be compatible with the DTS signal as indicated by a DTS logo on the player’s front panel. Note that early DVD players may not be able to play DTS- encoded DVDs. This does not indicate a problem with the AVR 5550, as some players cannot pass the DTS signal through to the digital outputs. If you are in doubt as to the capability of your DVD player to handle DTS DVDs, consult the player’s owner’s manual.
Please note that some DVD players are shipped with their output set for Dolby Digital only. To insure that DTS data is being sent to the AVR, please check the setup menu system on your DVD player to make certain that DTS data output is enabled.
PCM Audio Playback
PCM (Pulse Code Modulation) is the non- com- pressed digital audio system used for compact discs, Non-Dolby Digital/DTS Laserdiscs and some special PCM encoded DVDs. The digital circuits in the AVR 5550 are capable of high quality digital- to-analog decoding, and they may be connected directly to the digital audio output of your CD/DVD or LD player (LD only for PCM or DTS programs, for Dolby Digital laser discs an RF adapter is needed, see ”Dolby Digital” above).
Connections may be made to either the Optical
or Coaxial inputs on the rear panel or the front panel Digital Inputs *Ó.
To listen to a PCM digital source, first select the input for the desired source (e.g., CD) to feed its video signal (if any) to the TV monitor and to provide its analog audio signal for recording. Next press the Digital Select button ÛG and then use the ⁄/ ¤ buttons Don the remote, or the Selector buttons 7$on the front panel, until the desired choice appears in the
Lower Display Line B, then press the Set but- ton @Fto confirm the choice.
During PCM playback the unit automatically will turn to the default surround mode or to the LOGIC 7 mode but you also may select any surround mode except Dolby Digital or DTS. When an HDCD encoded disc is being played (see below) and the CD player is connected to the AVR 5550 via a digital connection, select Surround Off as the Surround mode to enjoy the benefits of the HDCD process.
HDCD
HDCD, which stands for High Definition Com- patible Digital®, is a sophisticated process that enables the AVR 5550 to deliver outstanding digital-to-analog decoding of PCM signals from any DVD or CD player, connected to a digital input on the AVR 5550 even when normal, non-HDCD-compatible players are used (only a digital output is needed).
When a CD with the HDCD recording is played, the AVR 5550 is able to take advantage of the special recording process that is used in the creation of HDCD disc. The special circuitry enables audio with extraordinary fidelity, stunning resolution and the highest possible overall quality.
As long as a digital input and the pure Stereo mode (Surround Off) are selected, the AVR 5550 will automatically sense that it is an HDCD recording.
It is important to note that the HDCD process is completely compatible with standard recordings. Indeed, the high-quality digital-to-analog circuitry that is part of HDCD and the HDCD decoder chip, replacing the monolithic digital filters used in conventional DACs, will enable enhanced performance also with normal, non-HDCD encoded program material.
MP3 Audio Playback
The AVR 5550 is one of the few A/V receivers to provide on-board decoding for the MP3 audio format used on specific computer audio files and by portable MP3 players/recorders. In addition, some new CD and DVD players are capable of playing back optical discs that are recorded with MP3, rather than standard CD audio information. By offering MP3 decoding, the AVR 5550 is able to deliver more precise conversion of the digital signals to an analog output, along with the benefits of listening to MP3 audio through the AVR 5550’s high current amplifier and the speakers from your surround system, rather than the smaller speakers and low powered amplifiers typically used with computers.
, HDCD