Focusrite ISA C8X 26-Input 28-Output 8-Preamp USB-C Audio Interface w/ 2 x ISA Preamps

Focusrite's ISA C8X is a 2U rack–mounted audio interface built around the company's signature ISA preamp topology, combining eight remotely controlled microphone preamps with comprehensive I/O and routing flexibility. The first two channels feature genuine ISA preamps with Lundahl LL1538 transformers and switchable impedance (800Ω, 1400Ω, 2400Ω, 7000Ω), while all eight channels deliver up to 79dB of gain and operate via front–panel control or Focusrite Control 2 software. This design targets studios and touring rigs that demand transparent, tonally refined preamplification alongside the practical infrastructure of a modern interface.

The ISA C8X provides 26 simultaneous inputs and 28 outputs through a 24–bit/192kHz converter with 116–117dB of dynamic range and noise floors below –127dB. Beyond the eight XLR microphone inputs with independent phantom power, the unit includes eight line inputs, two instrument inputs, 10 line outputs, two headphone outputs, dual ADAT pairs (16 channels at 44.1/48kHz, 8 at 96kHz), S/PDIF, MIDI, and word clock I/O. The two ISA preamps offer all–analogue Console and 430 Air modes for tonal shaping, whilst every channel includes 75Hz high–pass filtering at 18dB/octave, balanced inserts, and 16dBu maximum input levels at minimum gain.

Talkback and loopback functions enable practical studio workflows, and the interface connects via USB Type–C (USB 2.0 protocol) without bus power, drawing 40W maximum. This connectivity footprint suits both fixed installations requiring deep routing control and mobile setups that benefit from compact rack formatting. The combination of transformer–based microphone stages, extensive digital connectivity, and software recall makes it relevant for mastering, mixing, and multitrack recording environments where signal integrity and workspace scalability matter.

Features

• Eight remote–controlled microphone preamps with up to 79dB gain range
• Two ISA preamps with Lundahl LL1538 transformers and switchable impedance
• 26–input/28–output configuration at 24–bit/192kHz via USB Type–C
• Dual ADAT pairs (16 channels at 48kHz, 8 at 96kHz) plus S/PDIF connectivity
• Noise floor of –127dB EIN and –128dB input EIN (A–weighted)
• Console and 430 Air modes for analogue tonal shaping on all channels
• 75Hz high–pass filter at 18dB/octave on every mic input
• 2U rack–mounted form factor with talkback and loopback functions