Latency

For Audio Devices

For Dante audio devices, variation in latency in the network is compensated for at the receiver. Each receiver has a device latency setting. This setting defines the latency between the timestamps on the incoming audio samples and when those samples are played out.

The typical default latency for a Dante audio device is 1 msec. This is sufficient for a very large network, consisting of a Gigabit network core (with up to 10 hops between edge switches) and 100 megabit links to Dante devices. Smaller, Gigabit-only networks can use lower values of latency (down to 150 µsec for very fast devices, such as PCIe cards). Recommended latency settings are displayed in Dante Controller, and may also be found in the documentation accompanying the product.

Latency is set on the receiver. However, when a subscription is made, there is an automatic negotiation process between the receiver and the transmitter, to ensure that the latency for the subscription is high enough to prevent packet loss.

For example, Ultimo devices support a minimum of 1ms latency. If a faster device (such as a PCIe card) is set to 0.25ms latency, and is then subscribed to an Ultimo transmitter, the latency used for the subscription will be 1ms, which is the minimum supported latency for the subscription. Subscriptions to other devices (such as a Brooklyn II device) will be set at 1ms (or whatever latency the receiver is set to). This effectively makes the device latency setting a 'default' latency, which is used unless the transmitter doesn't support it.

Note:  The minimum latency available for a device connected to a 100 Mbps network port is 1 msec.

Using a latency lower than 1 msec over a 100 Mbps link will result in a subscription error, with the tooltip 'Tx Scheduler Failure'.

Latency Monitoring

Dante Controller provides latency monitoring for supported devices. For more information, see Latency Tab.

Latency and Dante Virtual Soundcard

Dante Virtual Soundcard allows a standard Apple Mac or Windows PC to function as a Dante device. Because Dante Virtual Soundcard runs on a general purpose computer without special hardware to support Dante timing requirements, additional latency needs to be added to connections received from a Dante Virtual Soundcard transmitter.

Dante Virtual Soundcard is configured with custom latency values for reliable operation. Dante devices with Rx channels that are subscribed to Tx channels from a Dante Virtual Soundcard transmitter will automatically configure themselves to use these higher latency values for those channels only. The latency on all other subscriptions on the receiver is unaffected.

Latency in DDM Networks

Devices that are enrolled in a Dante domain may support extra latency values, to accommodate larger network topologies.

If a device is un-enrolled while it is set to one of these latency values, its latency will be automatically reset to the default value for the device.

For Video Devices

For video (Dante AV) devices, the Device Latency setting in Dante Controller applies to the audio channels only.