Focusrite Clarett+ OctoPre 8-Channel Mic Preamp with ADAT Expansion

An Eight-Channel Preamp And Converter Built To Expand Any ADAT-Compatible Interface

The Focusrite Clarett+ OctoPre is an eight-channel microphone preamp and analog-to-digital converter designed to add substantial input and output capacity to an existing audio interface without requiring a full system replacement. Rather than functioning as a standalone recording interface, this unit connects to any manufacturer's ADAT-equipped interface, adding eight additional mic preamps and eight additional line outputs through optical ADAT connectivity, along with 24-bit, 192 kHz AD/DA conversion. Building on several generations of the OctoPre concept, this Clarett+ version brings Focusrite's proven Clarett+ preamp architecture into the mix, delivering a clean, transparent signal path with low noise and generous headroom rather than the deliberately colored sound of vintage-style analog preamps. For studios that have outgrown their current interface's input count but don't want to abandon a system that otherwise works well, this OctoPre offers a flexible, scalable way to add the channels needed for larger sessions, live tracking, and multi-microphone recording setups.

Eight Clarett+ Preamps With Classic Air Emulation

This unit is built around eight of Focusrite's Clarett+ microphone preamps, engineered specifically for a clean, low-noise signal path that preserves a microphone's natural character rather than imposing an artificial tonal signature. Each channel includes Focusrite's switchable Air circuit, an analog emulation of the company's celebrated ISA 110 preamp design, which introduces a gentle, sloped high-frequency boost starting around 100 Hz and reaching approximately plus 4 dB by 10 kHz. Engaging Air also alters input impedance to recreate the transformer resonance effect associated with that classic ISA design, giving engineers the option to add a touch of vintage analog character on top of the preamps' otherwise transparent baseline sound.

Substantial I/O Expansion Through Dual ADAT Ports

This OctoPre adds eight microphone preamps and eight line outputs to a connected interface, distributed across dual ADAT optical ports that handle 8 channels of digital audio transfer. At standard sample rates, this dual-port ADAT connection carries the full 8 channels, while S/MUX operation at higher sample rates allows the unit to maintain multichannel capability even when working at increased resolution. This kind of substantial I/O expansion is particularly valuable for studios tracking live bands, multi-mic drum setups, or any session requiring more simultaneous inputs than a primary interface offers on its own.

24-Bit, 192kHz Conversion With Excellent Dynamic Range

This unit delivers 24-bit, 192 kHz analog-to-digital and digital-to-analog conversion, giving engineers high-resolution recording capability well beyond standard CD-quality audio. With 118 dB of dynamic range and an equivalent input noise figure of negative 129 dBu, this OctoPre offers an exceptionally low noise floor, meaning even gain-hungry microphones like ribbon mics or distant room mics can be pushed hard without introducing objectionable hiss or noise into the signal. Independent testing has measured this unit's frequency response as nearly flat, within roughly plus or minus 0.05 dB between 20 Hz and 20 kHz, reflecting genuinely precise, accurate conversion rather than a colored or compromised signal path.

Flexible Insert Points And Instrument-Ready Inputs

Every channel on this OctoPre includes a switchable insert point, giving engineers the ability to route individual channels out to external hardware processors, such as compressors or EQs, before the signal continues into the recording chain. Two of the input channels double as Hi-Z instrument inputs using advanced JFET technology, allowing electric bass, guitars, and keyboards to be plugged in directly and captured with the kind of natural amp-like character that a proper instrument input provides, rather than requiring a separate DI box. This combination of insert flexibility and direct instrument input capability gives the OctoPre genuine versatility across vocal, instrument, and full-band recording scenarios.

Line Outputs Fed From Either Conversion Or Preamps Directly

This unit's eight line outputs can be fed either from its internal digital-to-analog conversion or directly from the connected preamps, giving engineers flexibility in how they route signal depending on their specific monitoring or outboard processing needs. Word clock input and output are also included, allowing this OctoPre to stay precisely synchronized with other digital audio equipment in a larger studio setup, an important detail for maintaining sample-accurate timing across multiple connected digital devices.

Universal 48V Phantom Power And Broad Interface Compatibility

All eight inputs on this OctoPre supply 48V phantom power, ensuring compatibility with the condenser and active ribbon microphones commonly used across professional recording sessions. Because this unit connects to any manufacturer's interface via standard ADAT optical connectivity rather than requiring proprietary Focusrite hardware on the other end, it works as a universal expansion solution regardless of which specific interface brand a studio has already invested in. This broad compatibility is a major part of what makes the OctoPre such a practical upgrade path, letting studios add significant preamp and I/O capacity without replacing equipment that already works well.

Who This Preamp And Converter Is Built For

Recording engineers, project studio owners, and mobile recording professionals who need to expand their existing interface's input count without a full system overhaul will find the Clarett+ OctoPre built specifically for that purpose. It's particularly well suited to studios that regularly track live bands, multi-mic drum kits, or larger ensembles requiring more simultaneous inputs than a primary interface can handle alone. For anyone who has found real value in their current interface but simply needs more channels, this OctoPre offers a clean, professional-grade way to grow a studio's capabilities.