How do I use all inputs on my Focusrite audio interface

Applies to all Focusrite audio interfaces with digital inputs

There are several types of inputs on Focusrite audio interfaces. These can be split into two main categories: analogue inputs and digital inputs.

Analogue inputs include microphone, instrument, and line-level. You can use these to connect audio devices directly. To learn more about the different types of analogue inputs on your audio interface, see:

What are the differences between mic, line, and instrument level?

Digital inputs include S/PDIF and ADAT inputs, you can connect digital audio sources such as another audio interface or an external preamp with digital outputs, such as an OctoPre.

The S/PDIF connection can send two channels of digital audio into the interface via the coaxial RCA connector (shown below) on the back of the unit.

You can use the optical port (shown below) on the back of the interface to receive an additional eight channels of digital audio when running at single-band sample rates (44.1kHz/48kHz) over ADAT. On some models, you can configure the optical ports to receive two channels of optical S/PDIF instead.

The number of inputs varies based on which interfaces you're using and how you configure your interfaces. For the full input listing, see the user guide for your interface.

Focusrite Downloads

For example, on the Scarlett 18i20 4th Gen, there is a maximum of 26 inputs at 44.1 kHz or 48 kHz. These are