Streams

Distribution of data is done via UDP in an IP-based network. The maximum number of streams in a network is depending on the network infrastructure and also in the stream settings and can not be generalized. This page gives a brief summary of the technologies used.

The maximum number of streams depends on packet time configuration.

Without 52-8541 license

Packet Time	Packet samples (48 kHz / 44.1 kHz)	Maximum number of streams	Notes
125 microseconds	6	16	Compatible with class A AVB transport
250 microseconds	12	32	High-performance, low-latency operation
333 microseconds	16	32	Efficient low-latency operation
1 millisecond	48	32	Required common packet time for all devices according to AES67 standard

With 52-8541 license and redundancy disabled

With 52-8541 extended feature upgrade AES67 license and redundancy disabled.

Packet Time	Packet samples (48 kHz / 44.1 kHz)	Maximum number of streams	Notes
125 microseconds	6	32	Compatible with class A AVB transport
250 microseconds	12	64	High-performance, low-latency operation
333 microseconds	16	64	Efficient low-latency operation
1 millisecond	48	64	Required common packet time for all devices according to AES67 standard

With 52-8541 license and redundancy enabled

With 52-8541 extended feature upgrade AES67 license and redundancy enabled.

Packet Time	Packet samples (48 kHz / 44.1 kHz)	Maximum number of streams	Notes
125 microseconds	6	16	Compatible with class A AVB transport
250 microseconds	12	32	High-performance, low-latency operation
333 microseconds	16	32	Efficient low-latency operation
1 millisecond	48	32	Required common packet time for all devices according to AES67 standard

The AES67 RAVENNA interface uses Zeroconf and SAP (Session Announcement Protocol) for service discovery and stream advertisement.

The AES67 RAVENNA interface supports the following codecs as RTP payload formats, in which audio is digitalised and formatted:

Codec	Description	Defined in
L16	16 bit linear	RFC 3551
L24 - (Default)	24 bit linear	RFC 3190

Tip
The AES67 RAVENNA interface additionally supports AM824 codec for decoding on RX side.

DHD Series 52 devices generally support sample rates of 44.1 kHz and 48 kHz. For more information on sample rates within RAVENNA AES67 interfaces, see Synchronisation.

Maximum Stream Channels

The AES67 RAVENNA interface calculates the maximum stream channels by packet time and encoding format. Another factor that must be considered is network MTU (Maximum Transmission Unit). The AES67 RAVENNA interface has a DSP limit of max 32 stereo channels per stream.

To overview and edit streams, go to Streams page in the web interface. Here you can enable streams and change settings on the TX side and on the RX side. To switch between TX and RX side, click TX STREAMS or RX STREAMS on top of the page. On touch enabled devices, you can also swipe with one finger to the left or to the right.

Note
This page is PIN protected, if PIN protection is enabled. See Installation and Maintenance for information on how to set up PIN protection.

Status colors for streams

The first column of the TX STREAMS and RX STREAMS table shows the number and the status of each stream. A stream status will only be shown if the stream is enabled. The following stream status indications are available: