LAWO POWER CORE - Configuration Example

Power Core User Manual Version: 6.6.0/3 79/539
9. Audio IO
9.3.3 Configuration Example
In the example described below, the network topology shall be a single Layer 2 switch using hitless merge with an
external PTP GrandMaster clock, and four connecting Power Cores on two announcement rings. For the first
Power Core the Sat Receiver inputs will be available to all other systems, whereas the Codec inputs will be
available to the first two systems only. There are four parts to the configuration:
Ø Step 1 - Configure the Output Streams for each Power Core
Open the "Audio Output -> RAVENNA" branch of the 'Tree Definition', select the RAVENNA Out 1-64 tab, and
edit the parameters as follows.
Group
Give each Power Core a descriptive and recognizable Group name, such as CORE1..4. The Group name
can be up to 8 characters, and shall start with an alpha character and not a numeral.
Name
Each outgoing stream for the Group shall also be given a descriptive name, e.g. SatRx01..08, Codec01..06,
etc. Remember, as above, to keep to the 8 character limit.
Default Audio
In this example the “baseband” inputs are being converted to AoIP streams and each should ideally receive a
default audio route from the corresponding input card. Double click on the pink cell and select the relevant
input.
Stream Size
In this example we are going to be using stereo streams. To optimize the packetizing process, 8 channels
streams could be selected or even larger to reduce overhead.
Codec
L24 = linear 24 bits, is a good standard to use.
Samples per
Frame
32 or 48 is typical for stereo streams. Do not exceed the MTU of 1500 bytes otherwise the packets will most
likely get fragmented by the switches (jumbo packets). 24 bit stereo samples with 48 samples per frame =
288 bytes. For example an 8 channel stream would have 1152 bytes.
Devices
The requirement for Hitless Merge means ra0 + ra1 should be selected. The stream will be transmitted on
both NIC’s and the SDP will let the receiver know that it’s a redundant stream.
Multicast
Address
The default range of multicast addresses will be used. The octets take a portion of their address from the
Ravenna NIC’s, namely the 3rd and 4th and are arranged as follows: 239.3rdoctet.4thoctet.x, where x
increments for each output stream starting from the first.
Discovery
The design called for two announcement rings. As this is a L2 network, mDNS Channels 1 and 2 shall be
used. Obtain (from network admin) and configure the multicast addresses according to the design. To do
this, open the "System -> Definition" branch of the 'Tree Definition', select the Ravenna tab and edit the
"Stream Announcement" settings. In CORE1..4 enable Channel 1 and in CORE1..2 enable Channel 2.
Return to the "Audio Output -> RAVENNA" and RAVENNA Out 1-64 tab. For the streams associated with
SatRx01..08, tick the mDNS checkboxes 1 and 2. For Codec01..08, tick mDNS 2 only.
Enable
Enter a True in the logic Enable field to ensure the streams get broadcast after startup.
Ø Step 2 - Configure the Input Streams for each Power Core
Open the "Audio Input -> RAVENNA" branch of the 'Tree Definition', select the RAVENNA In 1-64 tab, and edit
the parameters as follows:
Group
Give each Power Core a descriptive and recognizable Group name, such as CORE1..4. The group shall
start with an alpha character and not a numeral.
Name
Each input will receive a stream from the network and the question is whether to tie them permanently to the
input or give the input a generic name. In this example the input will be given a generic name, e.g. In001..032
and be made stereo to correspond to the streams on the network.
Stream Size
In this example we are going to be using stereo streams. To optimize the packetizing process, 8 channels
streams could be selected or even larger to reduce the overhead.
Default Stream
Include the stream name in the event that these inputs will always be connected to the relevant network
stream, e.g. CORE1:SatRx01
RAVENNA
Connect /
Stream Control
Instead of using the Default Stream position to enter a default stream, the RAVENNA Connect element
could be used for triggered subscription to streams, or the RAVENNA Stream Control element could be used
should there be Primary and Backup streams associated with the input.