Surround sound modes
The 640R has several music and home-cinema listening modes available. The output from the 640R will depend both on the source signal present, the speaker setup selected and the decode mode selected on the 640R. Before we describe how to operate the 640R, below is a brief guide to the Surround Sound formats that the 640R is compatible with:
Dolby Digital
Known also as DD (3/2) or DD 5.1, provides (up to) 5.1 output from suitable encoded Dolby Digital material, with 5 main channels (Front Left, Front Right, Centre, Surround Left, Surround Right) and a Low Frequency Effects Channel for the subwoofer, all discretely encoded. Decoding Dolby Digital requires a Dolby Digital encoded DVD disc and a digital connection from the source equipment (Such as a DVD player) to the 640R.
Note: Dolby Digital and DTS formats can sometimes carry less channels than their maximum such as Dolby Digital (2/0) which means a Dolby Digital encoded signal which is actually only carrying a two channel stereo signal (other channels inactive).
DTS
Known also as DTS (3/2) or DTS 5.1, DTS provides (up to) 5.1 output from suitable encoded DTS material, with 5 main channels (Front Left, Front Right, Centre, Surround Left, Surround Right) and a Low Frequency Effects Channel for the subwoofer, all discretely encoded. Decoding DTS requires a suitably encoded DTS disc and a digital connection from the source equipment to the 640R.
Dolby Digital EX
Known also as DD (3/3) or DD 6.1, an enhanced form of Dolby Digital. On top of the discretely encoded 5.1 channels DD EX provides an extra 6th channel (Surround Back, giving 6.1) matrix encoded into the rear surrounds for greater image depth and more solid sound localisation behind the listener. DD EX requires a DD EX encoded disc. DD EX is backwards compatible with DD 5.1 decoding. If DD EX is decoded as normal DD the Surround Back signal will be present in both Left and Right Rear Surrounds (forming a phantom rear centre). It can also be decoded as 7.1 by sending the Surround Back decode to both the Surround Back Left and Right speakers (forming two mono Back Surrounds).
DTS-ES Matrix
Known also as DTS (3/3) Matrix, an enhanced form of DTS. On top of the discretely encoded 5.1 channels DTS ES also provides an extra 6th channel (Surround Back giving 6.1), matrix encoded into the rear surrounds for greater image depth and more solid sound localisation behind the listener. DTS ES requires a DTS ES encoded disc. DTS ES material is backwards compatible with DTS 5.1 decoding. If DTS ES is decoded as normal DTS the Surround Back signal will be present in both Left and Right Rear Surrounds (forming a phantom rear centre). It can also be decoded as 7.1 by sending the Surround Back decode to the both the Surround Back Left and Right speakers (forming two mono Back Surrounds).
DTS-ES Discrete
Another enhanced form of DTS, also known as DTS (3/3) Discrete or DTS ES Discrete 6.1. DTS ES Discrete also provides an extra channel (Surround Back) for greater image depth and more solid sound localisation behind the listener, however in this case extra data is included in the bitstream so that all channels are discretely encoded. The Surround Back has greater separation from the other channels than is possible with matrix encoded technologies. DTS-ES Discrete requires a DTS-ES Discrete encoded disc.
DTS ES Discrete is backwards compatible with both DTS 5.1 and DTS ES Matrix 6.1 decoding. If DTS ES Discrete is decoded as normal DTS the Surround Back signal will be present in both Left and Right Rear Surrounds (forming a phantom rear centre). If DTS ES Discrete is decoded with DTS ES Matrix the Surround Back signal will be decoded separately (i.e. as 6.1) but by a matrix process, which will give the same channel separation as if the source disc were actually DTS ES Matrix (but not as good as DTS EX Discrete).
It can also be decoded as 7.1 by sending the Surround Back decode to both the Surround Back Left and Right speakers (forming two mono Back Surrounds).
Pro Logic II
The replacement for original ProLogic, Pro Logic II is a technology where 5 channels (Front Left, Front Right, Centre, Surround Left, Surround Right) are encoded into a Stereo mix by an analog matrix process. Dolby
Pro Logic II material can be played back by normal Stereo equipment (as Stereo) or decoded into 5 channel surround-sound.
Dolby Pro Logic II is compatible with the earlier 4 channel (Left, Centre, Right and mono Surround) Dolby Pro Logic system (which was the decoding counterpart to Dolby Surround encoding) as used widely on Video tapes, TV broadcasts and earlier films.
Note: Pro Logic does not include a Low Frequency Effects channel for the Subwoofer, but the 640R can create a Subwoofer output (for 5.1) via Bass management. Refer to the ‘Tone/Sub/LFE configuration’ section in the ‘Operating instructions’ part of this manual.
Pro Logic IIx
A newer version of Dolby Pro Logic II which is able to recreate 6 or 7 discrete surround sound channels (with fully stereo Back Surrounds in 7 channel mode) from suitable encoded stereo source material. Pro Logic IIx also has modes for post processing either Stereo material or 5.1 material into 6 or 7 channels whether or not it has been Pro Logic IIx encoded. When 5.1 decoding is required, Dolby Prologic II decoding will always be used by the 640R in place of Pro Logic IIx as IIx only works for 6 or 7 channel output.
Note: Pro Logic IIx does not include a Low Frequency Effects channel for the Subwoofer, but the 640R can create a Subwoofer output (for 6.1/7.1) via Bass management. Refer to the ‘Tone/Sub/LFE configuration’ section in the ‘Operating instructions’ part of this manual.
DTS Neo:6
A DTS technology which is able to recreate 6 channel (Left Front, Right Front, Centre, Left Surround, Right Surround, Surround Back ) surround sound from suitable analog matrix encoded stereo source material. DTS Neo:6 material can be played back by normal Stereo equipment (as Stereo) or decoded into 6 channel surround-sound.
Note: Neo:6 does not include a Low Frequency Effects channel for the Subwoofer, but the 640R can create a Subwoofer output via Bass management. Refer to the ‘Tone/Sub/LFE configuration’ section in the ‘Operating instructions’ part of this manual.
DTS Neo:6 can also be be decoded as 7.1 by sending the Surround Back decode to the both the Surround Back Left and Right speakers (forming two mono Back Surrounds).
DTS 96/24
A DTS technology that provides 5.1 channels of 96kHz / 24bit audio (along with video if required) on DVD-Video and DVD-Audio (video zone) discs (when suitably encoded in DTS 96/24). DVD players which allow 'DTS digital out' pass the DTS 96/24 bitstream over S/PDIF for decoding in the 640R.
DSP modes
These modes allow a realistic surround-sound experience from source material that has no encoding at all. The surround sound effect is achieved by Digital Signal Processing of the Analog or Digital stereo source used. Five modes are possible: PassThru, Theater, Hall, Movie and Music.
Other modes
Stereo/Stereo + Sub
Only the Front Left and Front Right speakers (and subwoofer if selected) have output in this mode. If an analog source is selected it will be converted to digital via 24 bit A/D converters to allow digital domain sub creation and bass/treble controls.
If a digital source is selected the 640R will be processing either LPCM stereo (from the digital outputs of a CD player for instance) or a Stereo downmix of DD or DTS material (from the digital output of a DVD player for instance).
Analog Stereo Direct
Selects the analog inputs for the current source directly with no A/D conversion, DSP processing, Bass/Treble or subwoofer channel active. Provides the very best fidelity for analog Hi-Fi source equipment. In this mode the 640R is acting just like a normal Hi-Fi integrated amplifier.
