User Manual

Using the AES16e
Selecting Play 2 (P2L and P2R) in the next set of Monitor Source Buttons down,
allows you to monitor audio from Play 1 and Play 2 out of Digital Out 1 at the
same time. If one application or playback stream is assigned to Play 1, and another
to Play 2, you would hear audio from both out of Digital Out 1. You can adjust the
relative level of these two sources with the volume slider directly underneath each
Monitor Source Button.
Similarly, Record sources can be added so that up to ten combinations of live
input, and pre-recorded playback can be routed and mixed to a single output. In
this way, headphone mixes, alternate house feeds, or a seamless blend of canned
and live broadcast material can be easily routed to appropriate outputs on the
AES16e card.
7.4 Clock selection and control
A valid clock source signal must be connected to the appropriate AES16e clock connector when the
PREFERRED CLOCK SOURCE is set to “External,” “Header,” “Lstream,” or one of the Digital Inputs. If
a signal is not present, the CURRENT CLOCK SOURCE will change to “Internal” until a valid signal from
the PREFERRED CLOCK SOURCE is restored. When an External clock source is selected, or when “Rate
Lock” is active, and an audio file or project file is played back at a different sample rate, either the audio
will play back at the wrong speed or pitch, or the Operating System will resample the playback stream to
match the current sample rate of the AES16e. In this case the audio speed and pitch will be fine, but there
may be undesirable consequences from this low-quality sample rate conversion. In general it is preferable
that the card’s sample rate matches the sample rate of the audio being played.
The AES16e also includes a SynchroLock clocking system to provide robust synchronization to degraded
input clock signals. Refer to Section 5.3 for a detailed description of SynchroLock.
7.5 AES/EBU Dual-wire operation
The AES16e supports dual-wire AES/EBU operation in which each physical input or output connection
passes a single channel AES/EBU signal running at half the system sample rate. This capability provides
compatibility with legacy devices that do not support single-wire AES running at sample rates greater than
50kHz.
Dual-wire mode can be enabled independently for inputs and outputs using the Dual Wire In and Dual Wire
Out controls on the Adapter window of the Lynx Mixer. See Section 6.2 for more information. When dual-
wire mode is enabled the number of available audio channels is reduced to eight.
With Dual Wire In enabled, the AES16e translates dual-wire input signals internally to input channels of
the on-board mixer according to the first table to the right. In this mode, input channels 5 – 8 are not active.
NOTE: Mixer Input Channel selection is available using the Input Source select buttons on the Record/Play
window of the Lynx Mixer. See Section 6.3. Record/Play Window.
AES16e User Manual
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