The AX32 Dante Card brings the potential for a huge number of channels both in and out of an AX32. One of the AX32’s strengths, other than its impeccable audio quality, is the scale of systems it can support which can become very large indeed.
The unexpanded AX32 chassis already offers 64 channels of Dante and AES67 courtesy of a built in Audinate module but additional channels of Dante can be added in blocks of 128 channels by adding Dante cards giving a maximum of up to 1088 channels at 48KHz. The clever bit comes from the fact that, as an expandable chassis, the AX32 can accommodate up to 8 Dante cards and because each of the Dante cards is a separate Dante adapter with its own Audinate module they can operate and route audio between devices running at different sample rates, something which isn’t possible on a single Dante network.
Can You Run Devices At Different Sample Rates On Dante Network?
Yes, but you can’t route audio between devices running at different sample rates. What this means in practice is that while the discovery of devices doesn’t rely on devices running at the same sample rate, creating connections between those devices and audio transport between them does. So while you could run a mixture of 48K and 96K devices on a single network, you could only route audio between devices running the same sample rate. Various workarounds are used to get around this, including bridging between the two sample rates via analogue connections between hardware devices. While this works it fundamentally compromises the usefulness of a Dante environment because the routing flexibility at which it excels becomes very limited by these bridging connections.
How Can I Route Freely Between Dante Devices Running At Different Sample Rates?
Each 128 channel Dante card installed in the AX32 chassis, and the 64 channel module which is pre-installed, show up as different devices in Dante controller and as such can run at different sample rates and interface with other equipment on the Dante network running at the same sample rate. Using DADman the AX32 can interface freely between all of the connected devices in the same way as they can between AES/EBU, MADI, SDI or any other connected audio source. Point to point routing via the DADman routing matrix allows all the flexibility of a purely Dante workflow but without the major restriction imposed by mixed sample rates.
Who Needs To Mix Sample Rates On A Dante Network?
There are some commonly described examples of live events running Dante at 96K sharing audio with broadcasters running Dante at 48K and while these are definitely good examples which illustrate the problem, are there any examples which are more directly relevant to studio engineers?
One excellent example from this article about using the MTRX, which is essentially an AX32 with a mini Digilink connector for Pro Tools use, in the Powerstation to record Omar Hakim’s band with Frank Fillipetti. The issue they had in this case was that the Powerstation’s cue system uses an Allen and Heath ME-1 personal monitor system which is limited to 48KHz. I think we can safely assume Frank was working at at least 96KHz, so without the routing flexibility and sample rate conversion offered by the MTRX, or by an AX32, these using wouldn’t have worked together.
There are of course many personal monitoring systems, which can work at high sample rates but there are quite a few which don’t, examples include the Aviom D400, the Allen and Heath ME1 and the Hearback Octo. Because many studios had already installed personal monitor systems before moving the rest of their studios over to Dante it is good to know that these legacy monitoring systems don’t necessarily have to be replaced because of shift to a Dante workflow and with a system like this they can be more flexible rather than becoming less flexible because of point to point bridges between systems.