Radial Engineering SB48

Radial SB-48 is a 2-channel phantom power supply with balanced XLR inputs/outputs to provide switchable +48 V or +12 V phantom power to condenser microphones or active DI boxes. Powered via 15 V DC adapter (included) and features status LEDs and power clamps. Uses a non-radiating charge pump circuit to ensure a stable, interference-free power supply in live and studio applications.

Typical applications

• Live performance: stable phantom power for condenser or DI box microphones when the mixer does not supply +48 V.
• Studio and recording: external power supply for microphones in configurations with interfaces or preamplifiers without phantom.
• Special microphone compatibility: support for microphones requiring +12 V via dedicated switching.
• Patch box and active DI uses: powers DI boxes that require phantom power to function properly in professional signals.

Technical features

The SB-48 is designed to provide stable phantom power even in audio systems that do not provide +48 V power, allowing the use of condenser microphones and active DI boxes on mixers, interfaces or PA systems without built-in phantom. The phantom voltage can be switched between +48 V and +12 V via a recessed switch, making it suitable even for special microphones that require 12 V.

The power supply section employs a nonradiating charge pump circuit, which produces a clean, oscillation-free power supply ideal for professional audio applications. The device includes a power indicator LED and a cable clamp to prevent accidental disconnection of the power cord.