Focusrite ISA 428 MkII Professional 4-Channel Microphone Preamplifier with Lundahl Transformers (AMS-ISA428MK2)

Focusrite ISA 428 MkII Professional 4-Channel Microphone Preamplifier with Lundahl Transformers (AMS-ISA428MK2)

The Focusrite ISA 428 MkII is a professional four-channel microphone preamplifier designed to deliver exceptional audio quality, flexibility, and classic Focusrite sound character for studio recording and professional production environments. Based on the legendary ISA110 microphone preamp design originally created by Rupert Neve, the ISA 428 MkII combines transformer-based circuitry with modern features to provide clean, detailed, and highly adaptable signal processing.

Featuring four renowned ISA preamps with Lundahl LL1538 input transformers, selectable input impedance, and dedicated front-panel instrument inputs, the ISA 428 MkII allows engineers and producers to capture vocals, instruments, and other sources with outstanding clarity and tonal versatility. Its 2U rackmount design includes four line inputs, switchable insert points, variable high-pass filters, and accurate LED metering for precise control during recording sessions. With an optional eight-channel A/D converter available, the ISA 428 MkII provides seamless integration with modern digital audio workflows, making it an ideal solution for professional studios, producers, and recording engineers.

Key Features

Four Premium ISA Microphone Preamps

• Includes four transformer-based Focusrite ISA preamps for exceptional clarity, warmth, and detailed audio capture.

Lundahl LL1538 Input Transformers

• Features high-quality Lundahl input transformers based on the original ISA design for classic analog character and superior signal integrity.

Selectable Input Impedance

• Provides multiple impedance settings, allowing compatibility with a wide range of microphones and enabling creative tonal shaping.

Four Front-Panel Instrument Inputs

• Offers direct instrument connections for guitars, basses, and other sources without requiring external DI boxes.

Professional 2U Rackmount Design

• Compact rackmount enclosure provides four channels of premium preamplification in an efficient studio format.

Dedicated Analog Insert Points

• Includes switchable inserts on each channel for integrating external processors such as compressors and equalizers.

Variable High-Pass Filters

• Features adjustable high-pass filtering to control low-frequency content and reduce unwanted rumble or noise.

Accurate LED Channel Metering

• Equipped with dedicated 6-LED meters on every channel for precise monitoring of input levels.

Expandable Digital Conversion

• Supports an optional eight-channel A/D converter with 122 dB dynamic range for high-quality digital recording integration.

Flexible Recording Applications

• Ideal for professional studios, vocal tracking, instrument recording, overdubbing, and high-end audio production workflows.