In this article, I’ll be covering a feature of Pro Tools called Satellite Link. Satellite Link allows you to link multiple Pro Tools systems over an ethernet network. Once linked, you can cue, play, and stop the transports, make play selections, and solo tracks across any of the systems from any linked workstation. Why would you want to do this? Well, there are two main scenarios:
Running the video on a separate machine to free up resources on the main computer which is running the audio. This is called Video Satellite, and the satellite machine can either be a Pro Tools system with a video file running in a session, or it can be an Avid Media Composer system. Using Media Composer as a Video Satellite means that you can run full quality video straight from the edit without having to export it as a single video file for use in Pro Tools. Running the video separately not only frees up resources on the main system, but it also allows the video to be run on a separate screen, giving you more space for the edit windows and plug-ins etc on the main system.
Linking multiple Pro Tools systems for audio playback. When it comes to huge post sessions, such as the kind which run to thousands of tracks for major film mixes, it can be advantageous, and in some cases completely necessary, to run audio from multiple systems. For example, you may have the multi-track music score running from one machine, with foley on a second, dialogue on a third and SFX on a fourth computer. Maybe there would also be a 5th machine acting as a layback system where you’d record all of the bounces.
For Satellite Link, a Pro Tools Ultimate system has to act as the ‘administrator’ computer. Additional systems can be linked to this as ‘satellites’. When not using Avid HD series hardware with a sync peripheral, a single satellite can be connected. Due to the lack of a synchronisation device, the satellite won’t run with sample accuracy, but it will be about frame accurate, which is good enough for a Video Satellite. With Avid hardware, and where all systems have a connected sync peripheral such as Sync HD or Sync X, up to 11 satellites can be linked to the administrator machine, for a total of 12 synchronised Pro Tools systems.
Granted, satellite linking several Pro Tools systems together for audio playback is not something which most of us have a need for, but Video Satellite in particular is certainly something which can be handy. Doing this of course requires not only two computers, but also a Pro Tools iLok licence for each one. If you have, for example, a main computer and a laptop, the laptop can be used for full-screen video playback while the main machine runs the session and audio. Let’s take a look at how to set this up.
Configuring A Video Satellite
It’s fairly easy to setup a Video Satellite and I’ll give a brief overview of the process here. In the configuration I’ll describe, one computer will be the main Pro Tools machine running the session with all of the audio (but no video) and the second computer will also run a session, but purely for video playback. The two sessions need to have the same start timecode and frame rate. Once this is configured, we can actually start setting up Satellite Link.
Both computers need to be on the same ethernet network. In a simple setup, this can be achieved by just connecting them to an ethernet hub. Next, on the machine which is to act as the administrator, go to Setup>Peripherals and click on the Satellites tab. Ensure that the mode is set to Administrator and also select this under System 1. The screen shot below shows how this looks when Avid hardware is used. We have the option of a total of 12 linked machines.
Or, if your administrator machine doesn’t have Avid hardware (ie, you’re using third party audio interfaces and no sync peripheral), you can still set the machine to be the Administrator, but only one satellite can be set. This is fine when the satellite is purely going to be running video.
How Do I Set The IP Address For Pro Tools Satellite Link?
It’s important that the Interface is set to the IP address of the ethernet network. Be sure that this is not set to the IP of your wi-fi, as this won’t work. The TCP/UDP port can usually be left at the default of 28282, but this can be changed if that port number is already in use elsewhere on your network, or in the unlikely event that you have more than one Satellite Link network operating on the same ethernet network.
Next, go into the same Satellites tab in the Peripherals page of the machine which you’ll be using as the Video Satellite. Configure this as a Satellite. This will grey out the Administrator section. Once again, be sure to select the correct IP address in the Interface section at the bottom. The TCP/UDP port should be set the same as that of the administrator machine.
Once this has been setup, go back into Peripherals>Satellites on the administrator machine and designate System 2 as your satellite.
We’re almost there now. In the Transport window of both machines, make sure that the Synchronisation controls are shown. A Link button allows you to link or unlink a machine from the satellite network. Other machines can be linked or unlinked by clicking their respective link buttons. The screen shot below shows a Satellite Link configuration with multiple machines running in a large post-production setup. If you’re only running a single Video Satellite, you would of course just see the administrator and satellite computer represented in the transport window.
Once linked, the machines will play in unison, responding to the transport controls on the administrator machine. You can choose to transmit and/or receive play selections using the orange and green arrow buttons in the transport window.
How I Use Video Satellite
For me, running my laptop as a Video Satellite means that I can keep my main computer purely for audio, and offload the video playback to my MacBook Pro. This has a number of benefits. Firstly, it means that I have more screen space for other things such as plug-ins and general edit window views on the main computer. Secondly, the screen size of the laptop is larger than I’d practically be able to run the video window if I was doing it all on one computer. Thirdly, I can disable the Avid Video Engine on the main system, which frees up some RAM and general system resources.
Summary
Satellite Link is a powerful feature, which allows Pro Tools systems to be synchronised over ethernet. I’ve focused on Video Satellite in this article because this is a feature which I use and find very useful in my own work. Satellite Link goes beyond this though, allowing for up to 12 machines to be linked for audio playback, as long as they all have Avid hardware and a sync peripheral for sample accurate synchronisation. For large post-production facilities running complex mixes, Satellite Link facilitates the playback of colossal sessions. Given that the Pro Tools HDX Hybrid Engine allows for 2048 voices, this would mean a potential maximum of 24576 voices in a system with 12 machines all running audio!
We’d be interested to know how many of the Production Expert community use Satellite Link. Do you run a Video Satellite, or perhaps even have multiple systems linked for audio playback? Let us know in the comments.