RME Fireface UCX II – 40-Channel Advanced USB Audio Interface

The Fireface UCX II is RME's most feature-dense compact interface, a half-rack unit that packs in what would typically require two or three full 19" panels of equipment. Designed for professional studio and live use, it combines a comprehensive analog and digital I/O set, fully standalone operation, direct USB recording, and RME's TotalMix FX routing engine into a single portable package.

Build and Format

The UCX II occupies just half a rack unit, making it practical for both desktop studio use and live rigs where space is at a premium. The front panel houses mic/line preamps, instrument inputs, a headphone output, and a full colour display with direct controls, while the rear provides balanced line I/O, digital connections, and word clock.

Audio Performance

The UCX II delivers professional-grade conversion throughout. Line inputs achieve an SNR of 112 dB (115 dBA), with THD below -110 dB. The mic preamps offer a 75 dB gain range with an EIN of -128 dBu, clean enough for ribbon microphones and any other low-output sources. Line outputs reach a dynamic range of 112 dB with output levels switchable between +19, +13, and +4 dBu. The headphone output delivers up to 210 mW into a 32 Ohm load.

Preamps and Inputs

The two front-panel XLR combo mic preamps feature individually switchable 48V phantom power and a 75 dB gain range. The two front instrument/line inputs accept both balanced TRS and unbalanced TS, with a 1 MOhm input impedance for direct instrument connection. At the rear, six balanced TRS line inputs provide extensive connectivity for outboard gear or additional sources.

SteadyClock FS

The UCX II incorporates RME's full SteadyClock FS circuit, providing jitter suppression exceeding 50 dB across all clock modes. The dedicated BNC word clock I/O makes it suitable for larger studio setups where multiple digital devices share a single master clock.

Standalone Operation

The UCX II can operate entirely without a computer. Six device states can be stored in internal memory and recalled directly from the front panel, making it practical as a live stage interface, standalone preamp and converter, or fixed install device.

DURec - Direct USB Recording

A dedicated rear USB port allows the UCX II to record all inputs and outputs directly to a USB drive or hard disk, completely independently of any connected computer. This DSP-driven recording can capture up to 40 channels simultaneously to drives up to 2 TB, and the same port supports playback for virtual soundchecks.

DC-Coupled Outputs

All line outputs on the UCX II are fully DC-coupled, meaning they pass CV and Gate signals directly to Eurorack and other modular formats, allowing the UCX II to bridge a DAW and a hardware modular system without additional hardware.

TotalMix FX

The UCX II ships with TotalMix FX, running on the unit's own FPGA chip, providing fully independent routing of every channel to any output with per-channel 3-band parametric EQ, 9-band Room EQ, dynamics, reverb, and delay. TotalMix Remote allows full wireless control from a tablet or second computer via Wi-Fi.

Key Features

• 40-channel, 192 kHz USB 2.0 interface in a half-rack form factor
• 2 x XLR combo mic preamps, 75 dB gain range, EIN -128 dBu, 48V phantom
• 4 x Analog inputs (front panel) + 6 x balanced line inputs (rear)
• 6 x Balanced line outputs, level switchable +19/+13/+4 dBu
• Headphone output: 210 mW @ 32 Ohm
• AES/EBU, ADAT, SPDIF coaxial, and word clock I/O
• SteadyClock FS with word clock BNC I/O
• Full standalone operation, 6 storable device states
• DURec: direct multitrack recording to USB drive, up to 2 TB, no computer required
• DC-coupled outputs for CV/Gate use with modular synthesizers
• TotalMix FX with 9-band Room EQ, dynamics, reverb, delay
• TotalMix Remote via Wi-Fi
• Class Compliant mode for driverless operation
• ARC USB remote control compatible
• RME in-house drivers, regularly updated with long-term OS support

AD — Line Inputs 5–8 (Rear)

• Resolution: 24-bit
• SNR: 112 dB RMS unweighted, 115 dBA
• THD: < -110 dB / < 0.00032%
• THD+N: < -104 dB / < 0.00063%
• Channel separation: > 110 dB
• Input: 6.3 mm TRS jack, electronically balanced
• Input impedance: 8 kΩ unbalanced / 12 kΩ balanced
• Input sensitivity: switchable +19 dBu / +13 dBu
• Variable gain: 0 to +12 dB
• Frequency response @ 44.1 kHz: 5 Hz – 20.8 kHz (-0.1 dB)
• Frequency response @ 96 kHz: 3 Hz – 45.8 kHz (-0.5 dB)
• Frequency response @ 192 kHz: 2 Hz – 92 kHz (-1 dB)

AD — Line/Instrument Inputs 3–4 (Front)

• Additional gain stage: 0 to +24 dB
• Input impedance: 1 MΩ (instrument) / 13 kΩ balanced, 9 kΩ unbalanced (line)
• Max input level (+19 dBu, Gain 0 dB): Line +19 dBu / Inst +13 dBu
• Max input level (+13 dBu, Gain 12 dB): Line +1 dBu / Inst -5 dBu
• Input mode: Line balanced (TRS) / Instrument unbalanced (TS)

AD — Microphone Inputs 1–2 (Front)

• Input: XLR, electronically balanced
• Input impedance: 5.4 kΩ
• Gain range: 75 dB
• EIN: -128 dBu A-weighted (60 dB gain, 150 Ω, 20 Hz – 20 kHz)
• Max input level (Gain 0 dB): +18 dBu
• Max input level (Gain 75 dB): -57 dBu

AD — Line Inputs 1–2 (Front, TRS)

• Input: TRS, electronically balanced
• Input impedance: 10 kΩ balanced / 5 kΩ unbalanced
• Max input level (Gain 0 dB): +24 dBu
• Max input level (Gain 75 dB): -51 dBu

DA — Line Outputs 1–6 (Rear)

• Resolution: 24-bit
• Dynamic range: 112 dB RMS unweighted, 115 dBA
• THD: < -108 dB / < 0.0004%
• THD+N: < -104 dB / < 0.00063%
• Channel separation: > 110 dB
• Maximum output level: +19 dBu
• Output: 6.3 mm TRS jack, servo-balanced
• Output impedance: 75 Ω
• Output level: switchable +19 dBu / +13 dBu / +4 dBu
• Frequency response @ 44.1 kHz: 0 Hz – 20.8 kHz (-0.5 dB)
• Frequency response @ 96 kHz: 0 Hz – 45 kHz (-0.5 dB)
• Frequency response @ 192 kHz: 0 Hz – 89 kHz (-1 dB)

DA — Headphone Output (Channels 7–8)

• Output: 6.3 mm TRS jack, unbalanced
• Output impedance: 1 Ω
• Max output level @ 0 dBFS (High): +19 dBu
• Max output level @ 0 dBFS (Low): +4 dBu
• Max power per channel @ 32 Ω, 0.1% THD: 210 mW

MIDI

• 1 × MIDI I/O via 5-pin DIN jacks
• Galvanically isolated via optocoupled input
• Hi-speed mode: jitter and response time typically below 1 ms
• Separate 128 byte FIFOs for input and output

Digital — Clocking

• Clock sources: Internal, ADAT, AES, SPDIF, word clock
• Jitter suppression of external clocks: > 50 dB (> 1 Hz)
• Effective clock jitter influence on AD/DA conversion: near zero
• PLL ensures zero dropout at up to 100 ns jitter
• Supported sample rates: 28 kHz – 200 kHz

Digital Inputs — AES/EBU

• 1 × XLR, transformer-balanced, galvanically isolated (AES3-1992)
• Accepts Consumer and Professional format
• Lock range: 27 kHz – 200 kHz
• Jitter suppression: > 50 dB (> 1 Hz)

Digital Inputs — SPDIF Coaxial

• 1 × RCA (IEC 60958)
• Accepts Consumer and Professional format
• Lock range: 27 kHz – 200 kHz
• Jitter suppression: > 50 dB (> 1 Hz)

Digital Inputs — ADAT Optical

• 1 × TOSLINK
• Standard: 8 channels, 24-bit, up to 48 kHz
• Double Speed (S/MUX): 4 channels, 24-bit, 96 kHz
• Quad Speed (S/MUX4): 2 channels, 24-bit, 192 kHz
• Lock range: 31.5 kHz – 50 kHz
• Jitter suppression: > 50 dB (> 1 Hz)

Digital Inputs — Word Clock

• BNC, internal termination 75 Ω (switchable)
• Level range: 1.0 Vpp – 5.6 Vpp
• Lock range: 27 kHz – 200 kHz
• Jitter suppression: > 50 dB (> 1 Hz)
• Overvoltage protection

Digital Outputs — AES/EBU

• XLR, transformer-balanced, galvanically isolated (AES3-1992)
• Output level: Professional 4.5 Vpp / Consumer 2.6 Vpp
• Sample rate: 28 kHz – 200 kHz

Digital Outputs — SPDIF Coaxial

• 1 × RCA (IEC 60958)
• Output level: Professional 1.2 Vpp / Consumer 0.6 Vpp
• Sample rate: 28 kHz – 200 kHz

Digital Outputs — ADAT Optical

• 1 × TOSLINK
• Standard: 8 channels, 24-bit, up to 48 kHz
• Double Speed (S/MUX): 4 channels, 24-bit, 96 kHz
• Quad Speed (S/MUX4): 2 channels, 24-bit, 192 kHz

Digital Outputs — Word Clock

• BNC
• Max output voltage: 5 Vpp / 4.0 Vpp @ 75 Ω termination
• Output impedance: 10 Ω
• Frequency range: 27 kHz – 200 kHz

General

• Power supply: external PSU (included)
• Typical power consumption: 13 W
• Dimensions with rack ears (W × H × D): 258 × 44 × 155 mm (10.16" × 1.73" × 6.1")
• Dimensions without rack ears (W × H × D): 215 × 44 × 130 mm (8.5" × 1.73" × 5.1")
• Weight: 910 g (2.0 lbs)
• Operating temperature: +5°C to +50°C (41°F to 122°F)
• Relative humidity: < 75%, non-condensing

Digital Downloads (buying software)

All software marked as "serial download" or "digital download" will be delivered via email within normal office hours.

Simply add the software to the basket and at the delivery stage in the checkout please select "Digital Download - Software by email" as your delivery method

Delivery Charges (Main Products)

The cutoff for same-day dispatch is 3:30pm but can vary at busier times such as Christmas.

All orders over £99.00 will be delivered free via our standard delivery 2-3 days (UK Mainland)

If you need your item faster we also offer a Priority Tracked service at £3.99 (1-2 days) or Next Day Tracked £6.99

(please ensure you add a mobile number to your order for tracking)

Saturday delivery is available when ordered before 2pm (Mon-Fri)

All orders below £99.00 will start as low as £2.99 depending upon weight and qty(s) (UK Mainland) 

All Delivery options will be available at the delivery stage in the checkout

EU Delivery Times

Non UK Mainland Addresses please allow 1-3 Days
Delivery To Belgium / France / Germany please allow 3-4 Days
Music PC Systems - Please allow 5-7 Working Days build time (UK) 7-14 (Rest of the World)

French - Pour la Livraison s'il vous plaît permet en France 2-4 Jours
German - Für Lieferung Nach Deutschland erlaubt bitte 2-4 Tage

Delivery Notes
On delivery, you must inspect the goods carefully for damage as Inta Audio is unable to accept responsibility for damage in transit, shortage of delivery or loss of products unless the customer advises Inta Audio of such within three working days from the date of delivery.

Returns Policy

We ask that you follow these guidelines to help us process your return as quickly and efficiently as possible:

1. Please keep your order reference to hand. This confirms your original order and gives us the necessary details to authorise the product’s return.

2. Contact our Customer Services Team on 02476 369898 (or e-mail cs@inta-audio.com). We will then send you an RMA number and returns form which needs to be completed and sent back with the returned item(s).

3. (If the order has been unpacked) re-package it to ensure that it is being returned in its original condition. Please make sure all items relating to the product are returned, including manuals and cables.

4. When returning an item please obtain a ‘proof of postage’ receipt from the Courier.


Returned items must be mailed within 10 days of when the RMA Number has been issued. Items received with a post date 30 days after your requested return will NOT be eligible for refund.

Please note: Our returns policy is quite straightforward but there are a number of conditions that we ask our customers to comply with before applying:

1. It is your responsibility to request a return. If you don’t tell us you want to make a return, we don’t know. Once you do tell us, we will do everything we can to action it.

2. If you have not requested a return within 28 days of receiving an order, we will have assumed that you are intending to keep it and we will not authorise a return.

3. We always refund the payment according to how the original purchase was made and aim to do so within 72hrs of the return being received by us.

4. Returned goods are liable for a restocking fee of 15% towards handling and repackaging if the order is not returned in its original, unopened packaging. This charge will be subject to our inspection of the returned goods.

5. Delivery charges will not be refunded unless the delivered goods are faulty.

6. Replacement products are dispatched immediately after the returned goods have been received and accepted by Inta Audio.

7. Items that develop a fault within 30 days of delivery are eligible for a replacement or a refund. Delivery costs are also reimbursed for faulty items. Please contact our Customer Services Team on 02476 369898 if you believe your item has developed a fault.

Finally, please remember that notifying us of your intention to apply for a return, saving the delivery paperwork and keeping the order in its original packaging will help both you and Inta Audio to process the return quickly.

If you have any questions about our Returns policy please telephone us on 02476 369898 or email us at cs@inta-audio.com.