System Latency And Delay Compensation; Connections And Cabling; Input And Link Connectors; Interconnection Options - Lab.gruppen PLM series Operation Manual

12. Application Guide
Pin 1: Ground/shield
Pin 2: Hot (+)
Pin 3: Cold (-)
Figure 12.5.1: AES connector wiring and
AES/EBU is a serial transmission format for linearly represented (uncompressed) digital audio data. It
describes a method for carrying two channels of periodically sampled and uniformly quantized audio signals
on a single twisted-pair cable. The data format allows for auxiliary data (which can be used for information
on signal characteristics) as well as the sampled audio data. The physical interconnection is defined by IEC
60958 Type I, which specifies three-conductor, 110-ohm twisted pair cabling terminated by an XLR connec-
tor.
The AES/EBU standard allows for multiple sampling rates and for resolutions of up to 24 bits. The PLM
Series accepts sampling rates from 44.1 to 192 kHz.

12.5.2 System Latency and Delay Compensation

It is important to note that all types of digital audio processing inherently involve some time delay, or latency.
If the processing chain does not involve analog-to-digital or digital-to-analog conversion, the amount of
latency is usually very small and often may be disregarded. However, in complex systems involving multiple
digital audio components and connections, enough delay may be generated to cause phasing problems.
Therefore, the least amount of latency is always preferred, and it is always important to consider system
latency delays when calculating and adjusting overall delay (as introduced by the Lake processor) when
time-aligning multiple loudspeaker systems.

12.5.3 Connections and cabling

12.5.3.1 Input and Link connectors

AES/EBU signal input is connected to the XLR-F connector designated "Input 1-2" in the AES/EBU input
section. An XLR-M connector, designated Link 1-2" is provided as loop-through output for daisy-chaining
multiple PLM units.
Note that the Input and Link connectors are identical for the analog and digital inputs, so care must be taken
when connecting PLM units, particularly when analog inputs are being utilized as a backup signal source.
Connectors should be clearly labeled to prevent confusion.
Never connect a digital signal source to an analog
input or an analog input to a digital signal source..

12.5.3.2 Interconnection options

When multiple PLM units will be receiving the same AES/EBU signal, connections may be configured in one
of two ways:
Daisy-chain – Connect the signal source (mixing console, "digital snake" or distribution amplifier) to the
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PLM Series Operation Manual rev 1.1.3
pinout