Focusrite AMS-ISA-828-MKII 8-Channel Mic Preamp Heritage Edition

The Focusrite ISA 828 MkII Heritage Edition is an eight-channel rackmount microphone preamplifier built around the revered ISA preamp topology. At the heart of each channel sits a Lundahl LL1538 input transformer, delivering the transparent-yet-characterful sound that has made the ISA series a studio staple for decades. With switchable input impedance — including the original ISA 110 setting — engineers can shape the tonal interaction between mic and preamp before the signal even hits EQ or processing. The variable high-pass filter (16–420Hz) per channel provides further control, letting you clean up low-end rumble at the source.

Beyond its eight mic inputs, the ISA 828 MkII offers dedicated line inputs with front-panel switching and instrument-level DI inputs on the first four channels, making it a flexible front end for tracking full bands or large ensembles. Each channel features a calibratable six-segment LED meter for precise gain staging. For studios that need digital output, an optional A-D converter card slots into the rear panel, providing Dante, ADAT, and AES3 connectivity at sample rates up to 24-bit/192kHz — along with switchable insert points that allow external processing to be patched in before conversion. The result is a professional-grade, high-channel-count preamp that bridges analog warmth and modern digital workflows.