Radial USB PRO Stereo DI for USB Source Level Control/Mono Sum
The Radial USB-Pro is a high-resolution stereo digital audio converter (DAC) and direct box that is designed to connect to any computer system to seamlessly transfer digital audio to analog. A stereo pair of balanced XLR audio outputs with adjustable level control then feeds the signal to a microphone preamplifier, PA system, mixing console or even a powered speaker! Made for plug and play simplicity, the USB-Pro will automatically be listed as an available sound card in the audio settings in all popular operating systems including Windows XP, Windows 7/8/10, and Mac OSX.
Connection to a computer is accomplished through a standard USB type-B port. Digital-to-analog conversion can be monitored on headphones through the 3.5mm analog output to check signal quality and level before connecting to a sound system. A mono-sum switch may be engaged to check for phasing or for connection to a mono system. Should hum or buzz caused by ground loops be encountered, two recessed side-access switches allow the user to insert isolation transformers into the signal path. To further reduce susceptibility to noise, this is augmented with a ground lift switch that lifts pin-1 on both XLR jacks.
As with all Radial products, the USB-Pro is designed to handle the rigors of professional touring. Our unique book-end design creates protective zones around the switches, connectors and controls to keep them out of harm's way. Inside, our time-tested I-beam construction assures the sensitive internal PC board will not torque, which could cause premature part failure. Finally, a full bottom no-slip pad provides mechanical isolation and electrical insulation to ensure quiet operation.






- High performance 24bit digital audio converter
- Ready to use without the need of a driver
- 3.5mm analog headphone output to check signal
- Balanced Lo-Z outputs with switchable isolation
- Designed to handle the rigors of professional touring
- No-slip pad provides mechanical isolation and electrical insulation
Product Specificatons
General
- Audio circuit type: Custom decoder with analog line drive
- USB compliance: USB 1.1 full speed
- Bit depth: 24bit (16bit capable)
- Sampling rate: 44.1kHz / 48kHz / 96kHz auto sensing
- Sound file compatibility: WDM, MME, CoreAudio, DirectSound, WASAPI and .WAV
- Software compatibility: Windows XP/Vista/Win7/Win8/Win10 and Mac OS
- Frequency response: 5Hz ~ 40kHz (30Hz ~ 18kHz with isolation)
- Dynamic range: >90dB
- Noise floor: -90dB
- Maximum gain: +8dBu
- Total harmonic distortion: 0.01%
- Stereo separation: 75dBu
- Output impedance: 250Ω nominal
- Digital input: USB connector B-type
- Analog output: Stereo balanced mic level (2 x XLR-M)
- Headphone output: 3.5mm TRS
- Level control: Variable, works on headphone and XLR outputs
- Isolation: Switchable for each channel
- Mono switch: Sums left & right inputs to mono
- Ground lift: Lifts pin-1 on both XLR outputs
- Power: USB bus powered 500mA maximum
- Finish: Durable powder coat
Physical & Dimensions
- Height: 48mm
- Width: 127mm
- Depth: 84mm
- Weight: 1.5lb