RME’s Next-gen UCX II with Femtosecond Clock

The RME Fireface UCX II packs exceptional performance into a rugged half-rack USB audio interface. Offering 20 inputs and 20 outputs, it features two reference-quality microphone preamps along with extensive analog, digital, MIDI, and word clock connectivity for seamless integration into virtually any studio setup. SteadyClock FS femtosecond technology delivers ultra-stable clocking, while DC-coupled outputs allow CV/gate control for modular synthesizers and other studio hardware. TotalMix FX provides complete routing, mixing, and latency-free effects without the need for an external hardware mixer, complemented by comprehensive onboard metering, DURec direct USB recording, and optional ARC USB remote support.

20-in / 20-out Power in a Half-Rack Design

Despite its compact half-rack footprint, the Fireface UCX II delivers remarkable flexibility and control. It includes two digitally controlled mic preamps, eight channels of balanced line-level I/O, line/instrument inputs, ADAT, AES, and S/PDIF digital I/O, MIDI connectivity, word clock I/O, and a dedicated headphone output. DC-coupled outputs expand creative possibilities for synth and control voltage workflows, while onboard peak and RMS metering ensures accurate gain staging. All of this is housed in a clean, space-saving design that looks as good as it performs.

DURec Direct USB Recording

The rear-panel DURec port enables direct recording and playback of up to 40 channels of audio to a USB thumb drive or external hard drive with capacities up to 2 TB. Powered by RME’s advanced internal hardware, DURec delivers reliable performance even with slower or multi-partitioned drives. Time-stamped recordings are made possible via an internal real-time clock, and advanced playback functions support efficient standalone operation without a computer.

Ultra-Stable SteadyClock FS Technology

Borrowing the same SteadyClock FS circuitry found in RME’s flagship ADI-2 Pro, the Fireface UCX II achieves extraordinarily low jitter performance. An upgraded analog PLL design, combined with Direct Digital Synthesis and a low-phase-noise quartz crystal reference, allows jitter levels that rival master clock operation—even while running in PLL mode. With jitter measured in femtoseconds, the UCX II delivers pristine timing accuracy for uncompromising audio fidelity.

TotalMix FX: Latency-Free Mixing and Effects

TotalMix FX equips the Fireface UCX II with a dual-DSP architecture, dedicating one processor to monitoring while freeing the second for real-time effects and processing. The mixer provides 20 hardware inputs, 20 software playback channels, and 20 hardware outputs, each with access to a 3-band parametric EQ, low-cut filter, compressor, expander, reverb, delay, echo, and auto level control. This allows artists and engineers to monitor and record with professional processing—completely latency-free.

Optional ARC USB Remote Control

For hands-on control, the optional ARC USB remote connects via USB and integrates seamlessly with TotalMix FX. It features 15 freely assignable illuminated buttons, a rotary encoder, and a footswitch input, offering intuitive desktop control over monitoring, mixing, and routing functions. Plug-and-play operation ensures instant recognition by TotalMix FX as soon as it is connected.

What RME Says...

The Fireface UCX II is a highly integrated pro audio solution designed for both studio and live recordings, delivering advanced features in an ultra-compact half-rack format. It continues RME's legacy of building compact yet feature-rich interfaces, condensing what would typically require multiple 19-inch panels into a single, portable unit.

Powerful & Portable USB Audio Interface

Capable of transferring analog and digital audio directly to Windows and Mac computers, the Fireface UCX II uses the latest Plug and Play technology for effortless installation. A well-designed Settings dialog and integrated routing solution provide fast, efficient operation, while the front panel features two mic/line XLR combo preamps, two digitally controlled line/instrument inputs, a headphone jack, control buttons, display, and main volume knob. The rear panel offers ten balanced line inputs and outputs, MIDI I/O, ADAT, AES/EBU, S/PDIF, USB 2.0, and switchable word clock I/O.

SteadyClock FS & Femtosecond Jitter Reduction

The Fireface UCX II utilizes RME’s SteadyClock FS technology, featuring femtosecond-level clocking and advanced jitter rejection. This ensures all analog-to-digital and digital-to-analog conversions maintain ultra-low jitter, delivering pristine audio quality across all digital formats.

Full Stand-Alone Functionality

All device states can be controlled directly from the front panel, allowing full stand-alone operation without a computer. Four keys, an encoder, a high-resolution color display, and a well-structured menu allow quick access to all settings. The internal memory stores up to six different unit states, enabling the Fireface UCX II to transform into different devices with a single button press. TotalMix FX can also be controlled via MIDI in stand-alone mode.

DURec – 40-Channel Mobile Recording

The integrated DURec digital recorder allows direct recording and playback of up to 40 channels to USB thumb drives or external hard drives up to 2 TB. Powered by the internal DSP, DURec operates independently from a connected Windows or Mac computer. This functionality converts the UCX II into a stand-alone field recorder or multichannel live player, ideal for virtual sound checks, live concerts, rehearsals, or spontaneous jam sessions.

TotalMix FX & DIGICheck

TotalMix FX provides comprehensive routing, monitoring, and latency-free effects, allowing multiple monitor mixes with EQ, dynamics, reverb, and delay for main outputs and headphone mixes. The optional TotalMix Remote offers real-time control via iPad or Windows/Mac. RME’s DIGICheck analyzer enables precise measurement and analysis of digital audio data for both recording and playback, ensuring professional-grade audio monitoring and troubleshooting.

DC-Coupled Outputs for CV/Gate Control

All line-level outputs are fully DC-coupled, allowing the sending of control voltages (CV) or gate information to modular synthesizers and other studio hardware. This is particularly useful in modular setups, providing stable low-frequency signals for pitch, LFO, and other control functions.

Class Compliant Audio & USB Connectivity

The Fireface UCX II operates in two modes: driver-based USB 2 and Class Compliant, making it compatible with Windows, macOS, and Linux systems without requiring proprietary drivers. Class Compliant mode provides basic operation, while full features are available using RME’s dedicated driver.

Reference-Quality Clocking & Room EQ

Featuring SteadyClock FS for reference-class digital clocking, the UCX II delivers excellent performance with ultra-low jitter and high-quality analog conversion. Room EQ in TotalMix FX provides optimized 3-band PEQ handling, 9-band PEQ, volume calibration, and crossfeed functions, allowing precise tuning of monitoring environments.