The Focusrite Scarlett 18i20 is rackmountable 24-bit 96 kHz USB 2.0 audio interface with eight Focusrite transparent, low-noise, low-distortion microphone preamps and a total of 18 inputs and 20 outputs including six combo XLR/jack microphone / line inputs plus two front-panel XLR/jack microphone / line level/ Hi-Z instrument DI inputs with 10 dB pad buttons, 10 analogue line level outputs, two independent headphone outputs on the front panel, and ADAT 8-channel I/O and S/PDIF digital stereo I/O, plus MIDI I/O and Word Clock out for digital synchronisation when required. The ADAT interface can be used to input digital sources or to add an extra eight microphone preamps such as Focusrite’s OctoPre Mk II.