9921-FS-OM (V1.18)
9921-FS PRODUCT MANUAL
1-17
Introduction
9921-FS Functional Description
Figure 1-7 Flex Mixer with Dual Mono Mixer Example
Internal Bus
(See Figure 1-5.) The internal bus receives its audio inputs from the input
routing function and accommodates a maximum of 16 concurrent channels.
This conduit serves as a centralized point for managing audio delay offset
from video and master gain controls for outputs from the input routing
function.
A bulk (master) video/audio delay function allows adding or reducing audio
delay from the video delay. The 9921-FS re-establishes video/audio sync
following framesync changes by applying an offset in small, progressive
amounts to provide a seamless, glitch-free retiming.
In addition to the master sync/delay controls, each bus channel has its own
independent delay and gain control.
As shown in Figure 1-5, the internal bus receives inputs directly from card
external sources or Dolby
®
decoder outputs as listed below.
•
Emb Ch 1-16
•
AES Ch 1-16
•
Analog audio Ch 1 - 8
•
Dolby
®
decode Ch 1-10
•
Silence
Automatic Audio Failover.
Automatic audio failover
(option
+AFO
) allows monitoring each of the card’s internal bus channels for a
user-configurable signal level threshold. If this threshold is not achieved
within a configurable holdoff time, the failover function allows an alternate
(“secondary”) channel to substitute for the primary channel.
Flex Mix Bus A
Emb Ch 1
Flex Mix A
Flex Mix Bus A
Flex Mix Bus A
Row 1
Row 2
Row 3
Emb Ch 2
Emb Ch 3
Flex Mix Bus B
Emb Ch 7
Flex Mix B
Flex Mix Bus B
Flex Mix Bus B
Row 4
Row 5
Row 6
Emb Ch 8
Emb Ch 9
To Internal Bus
In this example, rows 1 thru 3 all set to
feed to Flex Mix Bus A node results in
a mono mix on Flex Mix A.
A second, independent mono mixer is
facilitated similarly, with rows 4 thru 6
all feeding to Flex Mix Bus B node
resulting in mono mix output
Flex Mix B.
