Focusrite Scarlett 18i20 Audio Interface

This unit may show signs of heavy wear but is in good working condition.

The Focusrite Scarlett 18i20 Audio Interface is a USB audio interface for connecting microphones, instruments, line-level sources, and digital audio to a Mac or Windows computer via USB. It lets you route physical inputs into your recording software (DAW) and send your DAW’s monitor or playback mixes back out to the unit’s analogue and digital outputs for monitoring and outboard integration.

Connectivity for Recording and Expansion

With 18 inputs and 20 outputs total, the Scarlett 18i20 supports multitrack recording, hardware synths, and hybrid studio setups. The 8 analogue inputs handle mic, instrument, and line sources, while ADAT (8 channels) and S/PDIF (2 channels) provide straightforward digital expansion for additional preamps and converters.

Routing, Monitoring, and Studio Control

A fully assignable 18-in/16-out mixer gives flexible routing for creating monitor mixes, sending headphone feeds, or setting up outboard processing loops. MIDI I/O (5-pin DIN) supports common controllers and external instruments, and word clock output (BNC) helps maintain stable sync when integrating other digital gear.

Audio Performance and Supported Sample Rates

The interface supports sample rates of 44.1 kHz, 48 kHz, 88.2 kHz, and 96 kHz, with A-D dynamic range rated at 105 dB CCIR-RMS (all inputs) and D-A dynamic range rated at 103 dB CCIR-RMS (line outputs). Clock jitter is specified at < 250 ps.

Connections and Physical Specs

• Inputs (18): analogue (8), S/PDIF (2), ADAT (8)
• Outputs (20): analogue (10), S/PDIF (2), ADAT (8)
• ADAT I/O: 2 x TOSLINK optical connectors; 8 channels @ 44.1/48 kHz
• S/PDIF I/O: 2 x phono (RCA)
• USB: 1 x USB 2.0 Type B
• MIDI: I/O 2 x 5-pin DIN
• Word clock output: BNC
• Dimensions: 482 mm x 265 mm x 45 mm (1U)
• Weight: 6.6 lbs / 3kg