© 2013 Harmonic Inc.
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Ellipse 3000 r.3.0, Rev. B
Appendix D
Audio Pass Through Schemes Set-Up
The audio pass through coding schemes allow the user to transmit an audio stream without
encoding it. This coding scheme is useful for previously-encoded audio streams or for
maintaining audio quality when the user can afford the required bandwidth (usually
measured in Mb instead of Kb).
Transmitting pass through audio streams through the Ellipse requires an external
synchronization source between the Ellipse and any other equipment (such as the Dolby
encoder that sends the audio stream to the Ellipse).
To synchronize the equipment, the user may perform one of the following:
■
External Clock Source
– Set the Ellipse system clock to External. Synchronization is
performed between the Ellipse and the external equipment according to an external clock
source (see details in
■
Ellipse External Synchronization Interface
– The Ellipse is equipped with an external clock
interface. The clock is available at all times.
Upon creating a direct connection between the external equipment and the Ellipse clock
interface, the external equipment will be synchronized according to the Ellipse’s clock
interface (see Figure D–1).
NOTE:
The external synchronization interface is an AES3/EBBU transmitter at 48 kHz. The interface
complies with IEC-60958 and EIAI-CP1202 standards.
Figure D–1: Ellipse Clock Interface Synchronization
The Audio Pass Through Schemes specific-parameters menus are:
■
6.5.5 MPEG-4 HE AAC Parameters
■
Dolby E (see
6.5.8 Dolby E Pass Through Parameters Menu
■
Linear PCM (see
6.5.9 Linear PCM Pass Through Parameters Menu
NOTE:
The audio pass-through schemes are available upon permission only, with a correct license key.
Dolby Encoder
Audio Stream
Clock Synchronization 48 kHz
