User Manual

Multichannel Monitoring Tutorial Booklet (M2TB) rev. 3.5.2

Masataka Nakahara : SONA Corporation

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level according to the channel format.

However there is no guarantee that the playback of all consumer devices is being processed as described

in [Fig. 43], [Fig. 44]. It is desirable to obtain the output levels and output diagram for each device you

are using.

Some Dolby DIGITAL decoders for professional use also have bass management or surround attenuation

functionality.

[Fig. 45] and [Fig. 46] are simplified depictions of a portion of the output processing within the Dolby

Laboratories “DP564” professional decoder. [Fig. 45] shows the processing with bass management on,

and [Fig. 46] with it off.

[Fig. 45] Example of a signal flow of a professional decoder, Dolby DP564; Bass management ON

[Fig. 46] Example of a signal flow of a professional decoder, Dolby DP564; Bass management OFF

The difference with the consumer device shown in [Fig. 43] and [Fig. 44] is that regardless of whether

bass management is on or off, the input/output of all channels including LFE is constructed at unity gain,

and that the +10 dB for the LFE is obtained by the amp of the playback system. This means that when

using this type of professional decoder, you merely need to use a DVD-Video playback environment in

which the LFE playback gain is adjusted by +10 dB. For consumer devices that perform the same

processing, you will need to take the same actions.

In this way, when monitoring the decoder output in a studio in which the monitoring environment has

been adjusted for master production, it is necessary to know the output diagram of the decoder you are

using.

LPF2

SUB

LFE

Decode

Dolby AC-3

etc.

Att

HPF

LPF2

HPF

SUB

LPF1

-10dB

LFE

Decode

Dolby AC-3

etc.

Att