Focusrite ISA C8X 26-in/28-out USB-C Audio Interface with ISA Preamps

The First ISA Audio Interface

The Focusrite ISA C8X is a 2U rackmount, 26-in/28-out USB-C audio interface that builds the classic ISA transformer preamp into a complete studio front end for the first time. It combines the trademark ISA sound with eight preamps, extensive analog and digital I/O, routing, and full session recall, housed in anodised aluminium finished in Focusrite's original blue. An audio interface is the hub that converts analog microphone and instrument signals to digital for a computer and back again, and the ISA C8X does so at up to 24-bit/192kHz. For a modern studio that wants heritage tone with total control, it unites both in a single unit.

Two ISA Transformer Preamps

Channels one and two are genuine ISA preamps built around the Lundahl LL1538 transformer, the same transformer chosen for the ISA design in 1985, offering up to 79dB of gain. A transformer-coupled preamp passes the signal through an input transformer before amplification, delivering the warm, rich character that has defined ISA on decades of recordings. These two channels add switchable impedance, balanced inserts, and high-pass filtering, and for the first time in ISA's history they are fully remote-controllable. A vocalist or a key instrument can be tracked through reference-grade transformer preamps set from across the room.

Six Ultra-Low-Noise Preamps

Alongside the two ISA channels sit six Focusrite ultra-low-noise microphone preamps, each providing up to 69dB of detailed gain. These preamps add an analog Air mode for extra presence and a variable Drive control for harmonic saturation, giving every channel its own tonal options. With eight preamps in total, the interface captures a full drum kit, a band, or a multi-microphone ensemble in one pass. An engineer tracking a live session gains eight capable channels without reaching for an outboard rack.

All-Analog Console and 430 Air Modes

Two relay-switchable, entirely analog tone circuits give the ISA C8X its Console mode and 430 Air mode. Console mode introduces warm saturation and low-end punch through a variable soft-clip circuit, while 430 Air, lifted directly from the ISA 430 MkII, adds high-end shimmer via an inductor-based high-shelf filter. Because both are analog rather than digital emulations, they shape the signal before conversion with full-bodied, musical results. A mix engineer can print character to a track at the source rather than adding it later in the box.

Converters Shared with RedNet

Conversion runs at up to 24-bit/192kHz with as much as 125dB of dynamic range, using the same AD/DA converters found in Focusrite's flagship RedNet range. Analog-to-digital and digital-to-analog conversion, or AD/DA, is the pair of processes that translate analog audio to digital for recording and back to analog for monitoring, and wide dynamic range preserves both the quietest details and the loudest peaks. High-resolution conversion of this calibre means nothing is lost between the preamp and the DAW. Producers and mastering-minded engineers gain the resolution to capture, monitor, and mix with confidence.

Transformer DI Inputs and Auto Gain

Two front-panel instrument inputs route through the Lundahl transformers for a true console feel, with selectable impedance to preserve the natural tone of guitar and bass. A direct input, or DI, matches a high-impedance instrument to the interface so its signal records cleanly, and here it also passes through Console and 430 Air for added warmth. Multichannel Auto Gain sets optimal levels across all eight preamps at once, which is invaluable when time is short on a drum or multi-mic session. A band tracking live can be levelled in seconds rather than channel by channel.

Comprehensive Analog and Digital I/O

The rear panel carries eight fixed-gain balanced line inputs, twelve balanced line outputs across three monitor groups, and two class-AB headphone outputs with independent level control. Eight fixed-gain line inputs let outboard gear be patched once and left in place for permanent installations, while twelve outputs support monitoring from mono up to immersive 7.1.4. Two ADAT ports add up to sixteen channels of expansion, and S/PDIF, MIDI, and word clock make the unit a clock and MIDI hub. A studio can grow its channel count and drive multiple speaker sets from one interface.

Remote Control with Focusrite Control 2

Focusrite Control 2 for desktop and mobile lets you adjust every ISA C8X setting from the mixing position or anywhere in the studio. The software controls the preamps, Auto Gain, analog tone modes, routing, and monitor mixes on macOS, Windows, iOS, and Android, and it can save and recall complete session setups. Remote control keeps an engineer in the sweet spot rather than walking to the rack for every gain change, and recallable settings speed up recurring sessions and rotating rooms. Producers, studio owners, and installers gain repeatable, remote-managed workflows.

Standalone Operation, Software, and Ideal Users

Standalone operation lets the interface pass audio even when it is not connected to a computer, and it draws a maximum of 40 watts from AC mains rather than USB bus power. It ships with the Hitmaker Expansion software collection, including the bx_console Focusrite SC emulation of the ISA 110 and 130 modules and Oxford Reverb, with further Sonnox bundles available. Because it combines eight preamps, immersive-capable output, digital expansion, and full remote control, the ISA C8X suits professional tracking studios, immersive mix rooms, and permanent installations. It is a heritage-voiced interface designed to run an entire modern studio.