Focusrite ISA 828 MK2

The essentials to know about the Focusrite ISA 828 MkII microphone preamplifier

• 8 classic ISA preamps inspired by the Focusrite ISA 110 module, each input featuring a Lundahl LL1538 transformer for a rich and controlled sonic signature.
• Massive gain up to 80 dB (60 dB + 20 dB continuously variable trim): ideal for very sensitive recordings to demanding sources, from ribbons to soft vocals.
• Total studio versatility: dedicated mic and line inputs, plus 4 front-panel DIs for guitar, bass, or synth without external boxes.
• Designed for rack integration: front-panel switchable inserts, per-channel high-pass filters, LED metering per channel, and extendable via optional ISA ADN8 card for Dante, ADAT, and AES3 up to 24-bit / 192 kHz.

A revisited ISA heritage: the continuity of Focusrite sound in MkII version

Building on the design spirit of the Focusrite ISA 110 microphone preamp from the "Studio" console, the ISA 828 MkII continues the legacy of ISA preamps appreciated for their combination of transparency, gain reserve, and musicality. This MkII version preserves the sonic DNA (notably thanks to Lundahl transformers on each channel) while enhancing studio ergonomics and reliability for intensive rack use, featuring a switch-mode power supply designed to improve efficiency, reduce heat, and maintain silent operation.

Who the ISA 828 MkII is for: studios, live recordings, and permanent racks

The Focusrite ISA 828 MkII is designed for setups requiring eight channels of consistent quality: drum recording, acoustic ensembles, multi-mic setups, voice-over, or live capture with a reliable rack. Thanks to dedicated mic and line inputs, it is particularly suited for "always wired" installations: microphones ready to record, external preamp outputs, or processor returns, without needing to rewire the studio each session.

Key features: ISA impedance, inserts, filters, and digital expansion

Variable input impedance: a true color-shaping tool

Each channel offers a switchable input impedance to adapt the microphone load and explore nuances in tone, dynamics, and low-end response. The "ISA 110" setting restores the iconic impedance associated with the original preamp, useful for achieving a familiar feel on vocals, overheads, or acoustic instrument recordings.

Gain reserve, high-pass filter, and per-channel metering

The very wide gain range (up to 80 dB total) facilitates capturing low-level sources without unnecessarily raising noise floor. The per-channel high-pass filter, with a variable cutoff frequency from 16 to 420 Hz, helps clean up vibrations, proximity noise, or mechanical hum before processing. To maintain precise control during tracking, each channel includes a six-segment LED peak meter, individually calibratable, to align levels between microphones, musicians, and work environments.

Switchable inserts and external processing workflows

The front-panel switchable inserts make the ISA 828 MkII especially convenient with line-level processors such as compressors or equalizers: hardware processing can be integrated into the tracking chain without patching gymnastics, while maintaining a clear channel-by-channel architecture.

The MkII novelty: switch-mode power supply and ISA ADN8 expansion options

Compared to previous generations, the MkII version adopts a switch-mode power supply for better efficiency, reduced heat generation, and reliable, silent rack operation. For hybrid studios and networked setups, the ISA 828 MkII can also be expanded via the optional ISA ADN8 card, providing eight outputs in Dante, ADAT, and AES3 protocols, up to 24-bit / 192 kHz, allowing easy integration of the preamp into a modern digital environment.

Technical specifications

Type and architecture

• 8-channel microphone preamplifier
• Lundahl LL1538 input transformer
• 4 front-panel DI inputs
• Switchable input impedance, including classic ISA 110 setting
• Per-channel high-pass filter
• +48 V phantom power switchable per channel
• LED peak meter per channel
• Front-panel switchable insert
• Expandable with optional ISA ADN8 card

Connectivity

• 8 microphone inputs: XLR
• 8 line inputs: 6.3 mm jack
• 4 DI inputs
• 8 line-level outputs: Sub-D25

Gain and filters

• Up to 60 dB gain with an additional +20 dB continuously variable trim (up to 80 dB total)
• High-pass filter: variable cutoff frequency from 16 to 420 Hz

Format

• Chassis format: 19-inch rack - 2U

Expansion option (ISA ADN8 card, optional)

• Eight outputs with Dante, ADAT, and AES3 protocols
• Rates up to 24-bit / 192 kHz