eMotion LV1 Tutorial 1.7: I/O Sharing


Learn how to share the same stagebox between multiple eMotion LV1 mixers, by setting up eMotion LV1's I/O sharing option.

This short video tutorial will show you how to set up stagebox sharing between multiple eMotion LV1 mixers.

In this video, we’ll discuss:

  • Connecting multiple eMotion LV1 mixers to the same SoundGrid network
  • Enabling stagebox sharing
  • Patching shared I/O channels
  • Clocking in a shared system
  • Scenarios and behavior during failure
  • Shared pre-amp control

Let’s start with the basics:

An eMotion LV1 system consists of a host computer, an Ethernet switch, at least one SoundGrid server, and a least one SoundGrid I/O device. These elements communicate through a SoundGrid SOE network. All connected I/O devices within this system can be assigned and patched to the eMotion LV1 host.

Multiple eMotion LV1 systems can be linked by connecting their Ethernet switches. This enables hosts within this “super system” to build private networks from all connected I/Os, servers, and drivers. These assignments are exclusive—devices assigned to a host are available only to that host until they are un-assigned. Other users will see the devices in their System Inventories, but they will be grayed out and unavailable.

An eMotion LV1 system does not need the permission of other systems to assign an available device to its Inventory.

All devices in a super system—whether assigned to a host or not—are displayed in the Device menu of each independent system’s Inventory. Each connected host’s local driver is also shown.

A device assigned to a host’s inventory is the manager of the device. When a device is removed from a host, it becomes Free and can be assigned by any other host, which in turn becomes its manager.

For example, a 128-input MGB patched to four hosts will use up the 1 Gb network capacity of the SoundGrid network. In this case, the device will output 128 x 4 channels=512 channels (at 48 kHz).

Servers and drivers cannot be shared.

To set up device sharing, find the assigned device you wish to share and click its Sharing icon. The device is now sharable. Sharing can also be enabled from the Device menu. Only the manager of a device can activate its sharing.

Other systems can now assign the I/O device to their Inventories and patch available I/O channels. Output I/O channels patched by the manager cannot be shared with other systems until the device’s manager releases the patches or removes the device from its inventory.

All I/O devices assigned to a system need to be synced to the same clock source.

In this example, device A-IOS is shared with eMotion LV1 system B. This means that the device is now assigned to two independent systems (A and B) that must be synchronized to the same master clock device. In this scenario, A-IOS becomes the clock Master of System B—all other devices become SOE slaves.

It is possible to assign another device as the clock master while using a shared device, as long as all devices share the same clock.

Use each system’s Set Master menu to re-assign clock masters. Select the same device in both systems, if possible, and the clock will be common to both systems.

The shared device can now be a slave in the client system.

If the shared device cannot synchronize to the new clock, it will be unavailable for sharing by that host. Other eMotion LV1 hosts in the super system may be able to sync to the shared device if they can adjust their clocks accordingly.

A shared device can be a slave or the clock master of in its own SOE network, indicated by the M on the shared device’s icon. On the right, the device is still the SOE maser of the system it’s being shared with but is a slave within its own system.

When devices from more than two systems are assigned to a system’s inventory, all systems must be locked to the same master clock device.

Note that changing the master clock assignment in a system that includes shared devices will result in a clock reset in all associated systems. This results in a short audio dropout.

When a device is shared, all of its inputs are available to all users. The shared device appears in the Patch window with the non-shared devices.

Once assigned, a shared I/O device appears in the client’s Output Patch window. “IO Sharing, Remote Device” is shown on its icon. Patching shared I/Os follows the same conventions as patching unshared SOE devices.

As a client:

Select Remove from the Devices drop-down menu. Since the remote device is, by necessity, the local clock master, removing it will result in another device becoming the clock master. This prompt will appear. Once the device is removed, SOE clock will return to the previous master.

This may result in a short audio drop.

As the manager:

Deselect the Sharing icon, or uncheck Share in the Device menu, to end sharing for a device. If you attempt to remove a device that is being used by another system, this prompt will appear. You will not be able to un-share the device until it is not patched by other clients.

What happens if the sharing host becomes unavailable?

If the manager of a shared device fails: For example, if Ethernet connection is broken, computer stops working, computer is taken away), the shared device will continue to function. As long as the device is powered up and is connected to the manager’s SoundGrid network, it will pass audio. The device, however, is still owned by the missing host, so a client cannot access the device’s control panel.

To gain full control of the shared device, select “Manage Device” from the device’s menu. This, in essence, moves the device’s administrative privileges from the missing manager host to the client’s computer.

The device will now appear in the client’s inventory as a local SOE device. It can be designated as a clock master or slave of the SOE network.

If the absent manager system is sharing devices with yet other systems, this operation may interfere with some connections.

A device manager can enable all clients in a super system to adjust the preamp gain for a shared device. When Share Preamp Control is selected, any client host can adjust the preamp gain of any I/O channel of the device. All users sharing this device have equal control of preamp gain in any patched I/O channel.

For more information on how to control gain in multi-client environments and how to retain your gain structure while other users are controlling preamp gain, please refer to the eMotion LV1 manual.