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Dante Audio Over IP - What Is It And Why Should I Care?

Since its introduction in 2006 Dante has become the most popular AoIP technology. To place it in the AoIP landscape it is proprietary, owned by Australian Company Audinate. It operates on Layer 3. It differs from AVB/TSN in that AVB/TSN operates on Layer 2 and is an open standard. It is similar to RAVENNA in that it operates on layer 3 but differs from RAVENNA in that RAVENNA is open rather than proprietary. Because it operates at layer 3, it works over standard switches, unlike AVB/TSN. Dante can use 100 meg networks (with QoS), though the channel count is restricted to 32 each way. On a modern Gigabit switch channel counts of up to 512 each way are supported as are sample rates of up to 192kHz.

Audinate Hardware

While Dante Via offers the possibility of software only Dante networks, to get the lowest latency performance Dante uses proprietary hardware. I think of this as being like graphics processing. You can do it on your computer’s CPU but performance is much faster using dedicated hardware. Audinate don’t make consumer hardware, the business of bringing Dante equipped hardware to market is done through partner brands developing products using one of Audinate’s hardware modules - Audinate provide the bit which talks to the Dante network and partner brands build a product around it. The standardised network interface in all Dante equipped hardware is what gives the predictable performance. In terms of network performance Dante uses best-effort delivery using quality of service (QoS) to prioritise clock and audio data on mixed-use networks. It doesn’t have the deterministic behaviour of AVB/TSN but Audinate argue that the reserved bandwidth for guaranteed delivery model of AVB/TSN is only necessary when traffic exceeds the available bandwidth on the network. If the network is properly designed its bandwidth will exceed the maximum demand it will have placed on it and if this isn’t the case then the network isn’t properly designed.

There are currently over 250 Dante licensed manufacturers. This is far more than the next most widely supported technology, probably because of the relative ease and speed with which manufacturers can incorporate Dante into existing products or design new ones knowing that because of the proprietary interface module supplied by Audinate, from the network’s perspective all Dante hardware is one of four pieces of hardware. The current products supplied to manufacturers by Audinate are:

  • Brooklyn (in rack gear) - 64/64 @48KHz, 32x32 @96KHz, 16/16 @192KHz - This hardware can support AES67 but this is dependent on the relevant manufacturer releasing the firmware. Not all have done so yet, including Focusrite.

  • Ultimo (in the AM2 headphone amp and similar products) - 4x4 @48KHz, 2x2 @96KHz

  • Dante HC (in high capacity hardware) - 512x512 @48KHz, 256x256 @96KHz, 128X128 @192KHz

  • PCI-R cards (Focusrite and Yamaha) - 128x128 @48KHz, 64x64 @96KHz, 32x32 @192KHz

44.1KHz, 88.2KHz and 176.4KHz are all supported too but are omitted from the list.

The latency figures for Dante depend on how you are accessing the network. For low latency performance using hardware nodes round trip latency is around 3ms@44.1kHz however point to point latency from one device to another is as low as 150µs. For a computer running Dante Virtual Sound Card latency is much higher at around 10ms@44.1kHz. Dante Via has a similar network transmit latency of around 10ms but auxiliary signal paths such as USB audio devices will introduce further latency on top of this figure.

Difference Between RedNet And Dante

Focusrite were very wise to get into AoIP as long ago as they did and I’m sure many of us heard of RedNet before we heard of Dante. While RedNet is a Dante system, there are some minor differences between RedNet and Dante though none of them relate to the networking technology itself, I’ll cover this in another article. The main thing to appreciate is that while RedNet is Dante, Dante is not RedNet (i.e. there are parts of RedNet which aren't common to other Dante peripherals but the converse isn’t true).

Interoperability

I see this as Dante’s key strength. Because a Dante network is a network of proprietary devices all produced by a single company, it just works. It's very similar to the compatibility advantages of using exclusively Apple hardware in that all hardware is a known quantity. All Dante equipment is produced by a single company because although clearly Dante equipment is produced by many, many companies, because all these partner brands use Audinate’s hardware as the network interface in their various products, from the network’s perspective all hardware is Audinate hardware but from the user’s perspective there is a rich ecosystem of hardware with guaranteed interoperability.

Why Is Dante Doing So Well?

It certainly is doing well. The survey conducted by RH Consulting, which we recently invited Pro Tools Expert readers to participate in, shows clear evidence that Dante has assumed a dominant position in the market. It has overtaken the older generation of networked audio products and of the current generation, its proprietary, layer 3 model has meant it is deployable across currently installed networks and it is relatively straightforward and, crucially, quick to develop and bring products to market. That doesn’t mean that Dante has is any way won the race to become the de facto standard for networked audio distribution, but being widely supported, simple to use and so well established so early is a great position to be in. RAVENNA has its native compatibility with AES67 as a big plus, though Dante equipment running Brooklyn hardware is capable of supporting AES67 too. AVB/TSN has always been held back by its requirement for compatible switches. The switches issue is going to be less and less of an issue in the future as Cisco have finally begun production of AVB/TSN compatible switches.

Audinate’s approach to building market share is interesting because it illustrates a key difference in approach to the market. Dante is a product, not a standard like AVB/TSN. Because of this it is owned by a company who want it to do well, and offer support to manufacturers wanting to use their product. This support is part of the cost of implementing Dante but it supports manufacturers in supporting their customers and this offers direct access to live market feedback for product refinement and development. The difference between different AoIP technologies isn’t just technical, sometimes, like the difference between MacOS and Linux it is more than technical - it’s philosophical. The short term for Dante looks very positive as it offers ease of use and an excellent user experience. As for the long term - well who knows?

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