Description

SONOSAX SX-R4+ professional audio recorder, built around SONOSAX preamps, made for stand-alone field work

The SX-R4+ is designed around the world-renowned SONOSAX microphone preamplifiers: ultra low noise, high headroom, and the “natural” capture quality that SONOSAX is known for. It’s a true stand-alone 16-track production recorder compact enough for bag work, yet engineered as a serious location tool with disciplined metadata, redundancy, and professional sync.

A major part of the SX-R4+ appeal is that it delivers this performance in a machined aluminum chassis with a genuinely portable footprint (200 × 50 × 144.5 mm) and very low weight for its class (960 g without battery / 1.2 kg with 48 Wh battery).

The machine is also built for real set pace: it boots in 4 seconds and is ready to record immediately. Its 2.4″ pressure-based touchscreen remains usable in challenging conditions when gloves make capacitive screens impractical, you can still operate the UI reliably using a pen/stylus.

Fast operation and user-assignable shortcuts

• • Beyond raw audio performance, the SX-R4+ is built to stay fast on set. Key functions and the most-used menus can be assigned to quick-access “hot spots”, so the operator can jump straight to what matters without digging through layers.
  • Depending on the context, a simple press or a long press on a designated area of the touchscreen can trigger an action or open a specific menu. The same principle applies to the front-panel rotary/push control: press and long-press can be mapped to different functions for immediate access during takes.
  • This customizable action concept extends to compatible SONOSAX expansion accessories equipped with buttons and/or rotary controls, allowing operators to assign shortcuts and functions to external controls to match their workflow.

Recording, redundancy, and metadata

• • The SX-R4+ records up to 16 tracks as uncompressed BWF with iXML metadata.
  • It supports 44.1 to 192 kHz at 24-bit or 32-bit and offers 0.1% pull up/down for NTSC workflows.
  • For reliability on set, the SX-R4+ uses dual SD cards and can record to both simultaneously in Mirroring mode for instant redundancy.

Inputs & digital expansion including the 26-pin AES input connector

• • 4 × XLR-3F inputs, individually configurable as:
    • Analog mic/line (electronically balanced) with phase reverse, 48 V phantom, LF cut, and front-panel level control
    • Digital AES3 or AES42 (transformer balanced) with individual ASRC, plus phase reverse, LF cut, and front-panel level control
  • 2 × balanced line inputs on TA-3 with front-panel level control
  • TA-3 AES3 I/O (transformer balanced) that can be switched as input or output
  • 3M MDR 26-pin connector: 4× AES inputs + command bus
  • On the right side panel, the SX-R4+ includes a 3M MDR 26-pin multipin connector that carries 4 × AES3 inputs (AES 1–2 / 3–4 / 5–6 / 7–8) and the SX-R4+ command bus for system expansion.
  • Internally, the recorder implements four independent AES receivers, each with its own ASRC, allowing connection of non-synchronized digital sources. These AES receivers can be allocated either to the 26-pin AES inputs or to the XLRs when configured as digital (AES3/AES42).

Powering

• Removable 14.4 V / 48 Wh smart battery (SMBUS capable)
• External 9–18 V DC on Hirose 4-pin, SMBUS capable and electrically isolated
• 12 V regulated DC output for accessories (up to 7 W)

Expansion ecosystem 

• SX-AD8+ preamplifier: The SX-AD8+ expands the SX-R4+ input capability to up to 12 microphone inputs, enabling larger bag setups while keeping SONOSAX preamp quality across the rig.
• SX-LC8+ linear fader control surface + USB MIDI controller:  The SX-LC8+ adds 8 linear faders with function switches for more comfortable mixing control in the field. It also supports a USB MIDI mode for workflows/systems that accept MIDI control.
• SX-RC8+ front panel expansion + AES breakout + power distribution: The SX-RC8+ adds 8 rotary faders with function switches to extend mixing facilities. It also works as an AES breakout box for the SX-R4+ multipin AES input connector (providing 4 × TA-3 AES connectors for easier connection of AES sources such as digital wireless receivers). In addition, it provides power distribution (Hirose connectors), an additional headphone output, and a slate microphone capability.
• SX-RX8+ wireless-focused expansion module: The SX-RX8+ is an 8-channel HF extension module designed to integrate multi-channel wireless workflows with the SX-R4+. It includes a 98 Wh battery slot that can power the receivers and also help power the recorder, plus assignable encoders/push controls. Like the SX-LC8+, it can also be used via USB MIDI with other systems supporting MIDI control.

Options (choose one recorder configuration)

• Base (no option)
• 4-channel output module on XLR-5M (user-configurable output modes, including analog/AES combinations)
• Dante I/O (AoIP integration; PoE capable for single-cable power + audio)
• Sennheiser AMBEO VR mic on DIN 12-pin

Summary

Inputs / Outputs

• • • • 4x XLR-3F inputs, individually configurable as:
        – ANALOG: mic/line levels, electronically balanced, with phase reversal, 48V phantom, LF cut and level control on the front panel
        – DIGITAL: transformer balanced AES3 or AES42 with ASRC, phase reversal, LF cut and level control on the front panel
      • 2x Line inputs, electronically balanced on TA-3 with level control on the front panel
      • 4x AES3 balanced inputs on multi-pin connector
      • 1x AES3 balanced input with ASRC on TA-3 connector (shared with AES3 output)
      • 2x analog unbalanced line outputs on TA-3
      • 1x AES3 balanced output (user independent sampling frequency) on TA-3 connector (shared with AES3 input)
      • Up to 12x Mic inputs when connected to the SONOSAX AD8+
    • Optional audio over IP on RJ45 connector, such as Dante

Performance

• • • 135 dB (A-weighted) overall dynamic range from analog input to recorded file (114 dB (A-weighted) dynamic range with USA version)
    • 90kHz overall frequency response @192 kHz recording
    • 40 bits processing

Recording capabilities

• • • up to 16 tracks recording on 2x SD cards (SDHC, SDXC)
    • uncompressed BWF with iXML metadata
    • 44,1 up to 192 kHz @ 24bits or 32bits, Pull up/down 0.1% for NTSC world

User Interface

• • • Touch screen 2.4 » TFT color display
    • WiFi dynamic web-app interface

Powering

• • • Removable 14.4V 48Wh Lithium battery, SMBUS capable
    • External DC 9..18V on 4-pin Hirose, SMBUS capable, electrically isolated
    • 12V regulated decoupled DC output to power peripherals equipment up to 7W
    • Intelligent energy management with detailed on-screen information

Timecode

• • • Accuracy: 0.5 ppm
    • Independent in/out on Lemo connector
    • 23.976, 24, 25, 29.97DF, 29.97ND, 30DF, 30ND

Mechanical

• • Machined aluminum housing
  • Overall dimension: 200 x 50 x 144.5 mm (7.87 » x 1.96 » x 5.7 »)
  • Weight: 960g / 2.1lbs without battery, 1.2kg / 2.64lbs with 48Wh battery