Dolby Laboratories Multichannel Audio Tool DP570 - Manual (Page 71)

Dolby ® DP570 Multichannel Audio Tool User’s Manual 55
Chapter 8
Using the DP570 in
Master Control
Dolby ® E encoding is commonly used to distribute multichannel audio from a network
center to multiple affiliate stations, usually via satellite or optical fiber. The DP570 provides
quick and accurate emulation of multiple listening environments during Dolby E
encoding.
8.1 Connecting the DP570
Figure 8‐1 shows a typical setup for this application, where master control requirements
dictate that audio switching occurs discretely, and that the audio must be encoded into a
Dolby E signal prior to transmission. The source audio is a Dolby E stream, either played
out from a VTR or server, or received live through an IRD. The stream is processed by the
DP572, providing discrete signals to the master control switcher inputs. The switcher
output is sent to the DP571 for Dolby E encoding, and also to the DP570 for monitoring and
metadata modification.
Note: In this example, the metadata output from the DP572 decoder is passed through the
master control switcher via a serial layer. The “air” serial output is connected to the
DP571 and the “preview” outputs of the master control switcher to the DP570. More
than two metadata streams can be switched if necessary. The DP571 output then
gets multiplexed with video in the MPEG transport stream and sent for
distribution.