A__mic8 / A__digital8 User Guide
Version: 10.0.0/4
35/66
11. The RAVENNA Web UI
11.11.3
Editing the Payload Parameters
To define the payload, either choose a preset from the drop-down menu, or select
Custom
to edit the parameters
manually:
Payload Presets
Custom Payload Parameters
When editing the parameters manually, the payload is determined by three parameters:
·
Frame Size
= the number of samples per channel per network packet. The smaller the frame size, the
more often the sender transmits packets. This results in a lower sending latency, but also a higher
demand on the network's bandwidth. In Lawo devices, the Frame Size limits the number of TX streams
which can be created by each device.
·
Codec
= the encoding method used for the digital audio. For example:
L16
= 16-bit Linear PCM;
L24
=
24-bit Linear PCM;
AM824
= 24-bit Linear PCM + 8-bit metadata, a non-standard format commonly used
in AES/EBU.
·
Channel count
= the number of channels to be encoded: mono, stereo, 8-channel, etc.
It is the
Payload
which forms the bulk of the RAVENNA network packet size. In short, the more channels per
stream, the bigger the payload.
The other
Custom
parameter fields are:
·
DSCP
- assigns a DSCP (differentiated services code point) or quality class to the stream. The default
value =
46
.
·
Payload ID
- describes the format of the transported content. The default value =
98
.
·
TTL
(Time To Leave) - can be used to prevent data packets from circulating indefinitely. The default value
=
31
.
AES67 Compliance
An AES67-compliant stream requires the following parameters:
·
Bits per sample
= 24
·
Frame size
= 48
·
QoS (DSCP)
= 46 (=EF).
The simplest way to create an AES67-compliant stream is to choose the
AES67
preset.
