Applies to:

• Scarlett 3rd Generation 4i4, 8i6, 18i8, 18i20

This article will explain how to use multiple inputs on your interface in Voice over IP (VoIP) applications that will only accept incoming audio in stereo (two-channel), by utilising the Loopback feature. For more information about Loopback, see this article. This can be useful for several practices such as video lessons, conference calls, podcasting and even live-streaming, where you are using more than two inputs. Another advantage of using the steps in this article to set up your audio interface is that you can have a separate mix of audio for what your VoIP audience hears, compared to what you hear in your headphones/speakers which is commonly referred to as a “Mix-minus”.

The steps below will work for most non-ASIO compatible VoIP applications that only accept audio from two inputs of external audio interfaces, such as Zoom, Skype, Teams, Discord and Teamspeak.

Requirements:

• Install the latest version of Focusrite Control from here.

Important: Before going through the method below, follow the steps in this article to enable access to different pairs of inputs in non-ASIO apps

Method:

1. To start, open Focusrite Control and then go to File > Restore Factory Defaults. Your screen should look like the screenshot below.

2. Under the Output Routing section, select Loopback 1-2.

3. In the grey box for Loopback 1-2 select Custom Mix in order to choose which audio you wish to send to this output (Note: Custom Mixes are disabled at 176.4 & 192kHz)

4. With Loopback 1-2 selected, Mute Software Playback 1-2* in this Custom Mix so the VoIP caller(s)/audience cannot hear themselves.

*If you wish the VoIP caller/audience to hear audio from any other applications on your computer, you can keep Software Playback 1-2 unmuted in the Custom Mix and instead select a different pair of outputs (say, Line Outputs 3-4) in the VoIP application's audio settings. You will then need to ensure those Software Playback channels are added to the Custom Mix and muted when Loopback 1-2 is highlighted. By default, audio from your computer will play through Software Playback 1-2.

5. Add any other inputs you are using into the Custom Mix, by clicking on the + icon, and label them accordingly by clicking in the box above the fader.

6. In your VoIP application, select your interface in the audio settings, noting the application may display the input device as a Microphone and the output device as a Speaker. Ensure you select “Loopback” as the input.

8. You can now use faders in the Custom Mix for Loopback 1-2 to mix the levels of the inputs while you are live on the call. For example, if one person or instrument is much louder than another, it can be useful to turn them down using the fader. In addition, by selecting the Output your headphones or speakers are connected to, and assigning a Custom Mix to them in Focusrite Control, you can adjust the volumes separately for what you are hearing, compared to what the VoIP audience is hearing.

For a guide on how to do this with Scarlett 2nd Gen and Clarett USB interfaces, please see this article.