Focusrite Scarlett 18i16 4th Gen

The Focusrite Scarlett 18i16 is the largest desktop model in the Scarlett range — an 18-input, 16-output interface built around four mic preamps, ADAT optical expansion, and the 4th gen converter upgrade. It is the interface for producers and engineers who need to record multiple sources simultaneously, run a multi-room headphone setup, or integrate a full rack of outboard gear into a USB-connected studio.

The four 4th gen preamps match the quality of the smaller Scarlett models — 69dB gain range, Air mode per channel, Auto Gain, and Clip Safe. The additional inputs come from four fixed line inputs (for synths, drum machines, and hardware effects), eight channels of ADAT optical (for connecting an external preamp bank like a DigiMax or OctoPre at 44.1/48kHz), and two S/PDIF channels. The ADAT expansion is the headline feature: it transforms the 18i16 into a multi-mic recording interface capable of handling a full drum kit or a band tracking simultaneously, without needing a dedicated recording console.

The 4th gen update brought the RedNet-grade Cirrus Logic converters, improved 122dB dynamic range, and remote preamp control via Focusrite Control 2 software. The 18i16 is the only model in the 4th gen desktop range with four preamps — the 8i6 (still 3rd gen) has two.

Power is handled via USB-C, drawing up to 15W. Most modern computers supply this, but older or lower-powered USB ports may not — a 5V/3A power supply is included for machines that cannot deliver enough bus power.

On the used market the 18i16 is less liquid than the smaller Scarlett models given its more specialist use case, but it holds value reasonably well given the ADAT capability sets it apart from cheaper alternatives.

Who Is This For?

• Engineers recording live bands or drum kits who need more than four simultaneous mic inputs via ADAT expansion
• Project studios with existing outboard preamps who want to bring all channels into a DAW via ADAT
• Producers running complex hardware rigs needing multiple line inputs and outputs simultaneously
• Studios replacing a mixing desk with a DAW-centred setup requiring flexible I/O