Grass Valley DAP-1781 User Manual

Page 50

GUIDE TO INSTALLATION AND OPERATION

50 | DAP-1781

Note: The AutoMAX-II

algorithm is supported by firmware version 1.3.1.0 and later. Firmware version

1.3.0.0 supports only the AutoMAX

algorithm. The AutoMAX

algorithm does not support the upmix-to-

pass and pass-to-upmix transition speeds. The version number is available through the front panel menu
Status-upMax.

• Metadata Follow Mode & Reversion Mode

This process may be useful for sources that switch between 5.1 and stereo. The Coding Mode parameter in
the first program of the Dolby metadata will set the Operating Mode between PASS and UPMIX.

Note: In Follow Metadata mode, the metadata Generator will be automatically turned ON when the

upMAX

module is upmixing. The goal is to provide a valid metadata stream for the upmixed audio

content. The Generator content must have been previously configured with valid 5.1 metadata
parameters. The content of the Generator will be static except for the Dialnorm parameter of the first
program that will be continually overwritten with the Dialnorm value in the Primary metadata source
(when present). It is important to select an appropriate Backup Metadata source other than
Generator, configured with 5.1 metadata values, in case the Primary source becomes absent. When
the upMAX

module is set to Pass mode by the incoming metadata stream, the Generator will be

automatically turned OFF to let the incoming metadata stream pass through.

Metadata Follow Operating Mode

First Program Coding
Mode (ACMOD)

Reversion
Mode

Last Valid
Process

C/LFE, Ls/Rs
Levels

upMAX
Process

Metadata
Source

3/2

PASS

Primary

2/0

UPMIX

Generator*

Other

PASS

Primary

Absent

PASS

Backup

Absent

UPMIX

Generator*

Absent

Last Valid

PASS

Backup

Absent

Last Valid

UPMIX

Generator*

Absent

Last Valid

AutoMAX

Generator*

Absent

AutoMAX
(rev 1.3.0.0)

AutoMAX

Generator*

Absent

AutoMAX-II
(rev 1.3.1.0+)

Level >
Threshold

PASS

Backup

Absent

AutoMAX-II
(rev 1.3.1.0+)

Level <
Threshold

UPMIX

Generator*

* Generator: the Coding Mode of the Program 1 should be set to 3/2 or 3/2L

Adjustments
The “surround field” can be adjusted with the Center Width control and the Surround Depth control. The
bass enhancement signal for the LFE channel is derived from the Left, Center and Right channels. The LFE
Enable checkbox and LFE Channel Level slider control the LFE output.

Latency
This upmix process increases the delay through the DAP-1781 by 155 samples (3 ms + 11 samples). It will
be compensated as soon as the requested delay is larger than 5.5 ms.

Note: in mode UPMIX and AUTOMAX, the channels 15 and 16 are reserved for a future use and muted.

Note: when a non PCM signal, including AC-3 and Dolby-E, is detected at the L/R input, the six outputs of
the upMAX

module (channels 9 to 16) are muted.