Focusrite has announced the release of the ISA C8X, marking the first time its ISA preamp technology has been integrated into a complete USB audio interface. Released today, the ISA C8X expands the long-standing ISA range into a full studio hub, combining analogue design with modern digital control and connectivity.
The ISA series dates back over 40 years to designs created by Rupert Neve for AIR Studios. Those original concepts, including the use of Lundahl transformers, remain central to the ISA sound and are carried forward in this new interface. With the ISA C8X, that design is now part of a 2U rack-mounted unit built to handle recording, routing, and monitoring within a single system.
The ISA C8X features a 26-in, 28-out USB-C configuration, supporting both analogue and digital workflows. It is designed for studio environments where fixed installations, patchbays, and outboard equipment are part of the setup. Dedicated line inputs and a wide range of connectivity options allow for consistent routing without frequent reconfiguration.
At the input stage, the interface includes eight microphone preamps. Two of these are transformer-based ISA preamps using Lundahl LL1538 transformers, offering up to 79 dB of gain along with switchable impedance, inserts, and high-pass filtering. The remaining six preamps are ultra-low-noise designs with up to 69 dB of gain, designed for detailed signal capture and equipped with analogue Air processing and variable Drive DSP.
The ISA C8X also incorporates analogue processing options directly within the signal path. Console mode provides a variable saturation circuit that affects low-end response as the signal is driven, while 430 Air mode applies a high-frequency lift using an inductor-based filter design derived from earlier ISA hardware. These controls are available on the ISA preamps and instrument inputs, allowing tonal adjustments at the hardware level.
For conversion, the interface uses 24-bit, 192 kHz AD/DA technology derived from Focusrite’s RedNet systems, delivering up to 125 dB of dynamic range. Line inputs are designed with a direct path to the converters, bypassing preamps to maintain headroom and signal clarity.
Monitoring and output options are built to support a range of studio formats, including stereo and immersive setups. The unit includes twelve balanced line outputs, dual headphone outputs with independent control, and support for multiple monitor groups. Additional expansion is available via ADAT and S/PDIF, while MIDI and Word Clock connections allow integration into larger systems.
Control is handled through Focusrite Control 2, which enables remote management of gain, routing, and monitoring from desktop or mobile devices. The system also supports session recall and multi-interface setups. An Auto Gain function is included to set levels across all eight preamps simultaneously, supporting faster setup workflows.
With the release of the ISA C8X, Focusrite brings its established ISA preamp design into a fully integrated interface format, combining analogue circuitry, high channel counts, and modern control options within a single rack unit.