Article applies to:
Focusrite Control (Scarlett 2nd Gen: 6i6, 18i8, 18i20. Clarett range)
Scarlett/Saffire Mix Control (Scarlett 1st Gen: 6i6, 8i6, 18i6, 18i8, 18i20. Saffire range)
Pro Tools has a feature called a "Hardware Insert" where you can use a piece of outboard gear similar to a plug-in, in the Insert Section of your Channel.
Pro Tools will only use a Hardware Insert with the same Input and Output number, so you will likely want to use a channel 3, 4, 5, or 6, as 1/2 Outputs are typically used to connect Studio Monitors, and 7/8 and 9/10 are tied to the headphone outputs so you will want to leave these for the Main Mix as well.
In this example we will use Channel 3.
First, lets make sure your outboard gear is connected properly. Connect Line Output 3 from your interface to the Line Input of your outboard gear. Then, connect the output of your outboard gear to Line input 3 of your interface.
In Pro Tools go to Setup > I/O and make sure your Hardware Inserts are set up. In the screenshot below you will see a named Insert for 3/4 Inputs "Lexicon" for a 2-channel Lexicon unit to be connected on Inputs 3/4.
Then in the Insert area of your Track you can add one or both channels. The session only has a Mono Audio Channel to be processed, so you will just see "Lexicon.L" which is the Left Channel plugged into Input 3. Pro Tools also allows you to use the drop down triangles to name the individual channels differently if you prefer, rather than in pairs.
When using Focusrite Control (Scarlett 2nd Gen: 6i6, 18i8, 18i20. Clarett range)
The DAW output channels will need to be routed to the Physical Line Outs. In the Output Routing section of Focusrite Control, find Line Outputs 3-4 and make sure they are set to receive signal from Playback 3-4 (see screenshot below).
We also want to make sure that output 3 is sending full Line Level volume. With the Clarett range and the Scarlett 18i20 2nd gen, the monitor dial is a digital encoder that can allow control over multiple outputs. If the monitor dial is set to control output 3, then output 3 may not be sending full line level volume. (Note: for the 6i6 and 18i8, there are no monitor control options, so you can simply adjust the volumes with the gray vertical level sliders).
To confirm the output is at full line level, go to the Device Settings section of Focusrite Control and make sure the Monitor Controls are set to adjust only outputs 1-2 (see screenshot below). This means that the monitor knob on your interface will only adjust outputs 1-2 and will not affect the additional line outputs. The additional line outputs available can be adjusted through the vertical slider if not already set to max (top most position).
Using Scarlett/Saffire Mix Control (1st Gen: Scarlett 6i6, 8i6, 18i6, 18i8, 18i20. Saffire range).
The DAW output channels will need to be routed to the Physical Line Outs. In Saffire/Scarlett MixControl, find Line Output 3 and set it to receive signal from DAW 3. Do the same for Line Output 4 and DAW 4 (see screenshot below).
We also want to make sure that output 3 is sending full Line Level volume. With the Pro40, Liquid Saffire 56, and Scarlett 18i20, the monitor dial is a digital encoder that can allow control over multiple outputs. This is identified by any line outputs set to “blue” with the H/W Control button engaged in the monitor section.
To confirm the output is at full line level, be sure to Shift+Click on the Monitor Enable Buttons for Channels 3 and 4 (turning them “grey”) just above the Monitor Knob on MixControl. This unlinks the desired channels from that large Monitor Knob and sends a full Line Level volume. Always be careful not to shift click if gear such as speakers are plugged in, or you aren't 100% sure yet about your routing, as in some cases, say if you had a Mix containing Input 3 sent to Output 3, you can create a sudden feedback loop which can be VERY loud.
You have now created a Hardware Insert on 3, and have 4 available for another channel in your session as well! Remember to set the input level appropriately for the input receiving the signal from the external hardware.
With the inset added in Pro Tools, the DAW will now send signal out on the desired channel and bring it back in on the same track.