Radial J48 Stereo Active Direct Box

The Radial J48 Stereo Active Direct Box is a high performance active direct box designed for professional touring and studio recording. Featuring a unique internal switching supply that employs 48 volt phantom power and steps it up to increase the signal handling while it lowers distortion of all types, the Radial J48 Stereo is twice as good as the world's finest phantom-powered active DI!

The Radial J48 Stereo Active Direct Box features the same award-winning signal path that has made the single channel J48 the most specified active direct box on tour today. And with users as diverse as Paul McCartney, Tommy Emmanuel and Joe Chiccarelli, you can be sure it will meet the most demanding qualifications.

The design begins with a rugged 14 gauge steel construction and a bookend design that protects sensitive switches and connectors from damage. The internal I-beam construction ensures the fragile internal PC board will not torque, which in turn could lead to cold solder joints developing and premature failure. All connectors are made from glass-filled nylon and feature extra large nickel-silver contacts that will not tarnish over time.

Inside, a unique switching power supply converts the 48 volt phantom to AC, increasing the headroom for improved signal handling and lower distortion. This results in an exceptionally linear frequency response that spans from 10Hz to 40kHz while being able to handle high output instruments without choking. In addition, a -15dB pad may be engaged for extreme signal handling. This is supplemented with a high-pass filter that gently rolls off low frequencies below 80Hz to clean up mud and excessive resonance. A side-access 180º polarity reverse aids when using the Radial J48 Stereo with dual element pickups to either phase align the sources or eliminate acoustic hot spots that can cause feedback on stage.

A unique aspect of the power supply is the way that the Radial J48 handles buzz and hum caused by ground loops. The traditional solution is to lift the audio ground by disconnecting pin-1 at the XLR output. When this is done, the 48 volt phantom power from the console is shut off, forcing one to introduce a battery into the equation. Unfortunately, batteries are inconsistent, and when they begin to drop power, severely affect the available voltage and resulting headroom. Instead, the Radial J48 Stereo employs a DC to DC converter with a high frequency transformer that enables the audio ground to be lifted at the power supply. This does not shut off the phantom power and is invisible to the user.

The Radial J48 Stereo – Twice as good as the world's finest phantom-powered active DI!

Radial J48 Stereo Active Direct Box Features

• Ultra low distortion of all types
• Exceptional headroom & dynamic range
• Retains instrument's natural sound
• Powered by 48V phantom

Radial J48 Stereo Active Direct Box Applications

• Using the J48 Stereo with a keyboard - The Radial J48's active circuit and amazing signal handling makes it a great choice for both digital and old school analog keyboards. A built-in pad reduces the sensitivity if needed.
• Using the Radial J48 Stereo with two basses - The compact design makes it easy to connect two guitars using one direct box. The great sounding active circuit sounds as good as other DIs costing five times as much!
• J48 Stereo with two different instruments - Use the Radial J48 Stereo with two completely different instruments. The low crosstalk makes it a great choice when doubling between bass, acoustic guitar, fiddle, or mandolin.

Radial J48 Stereo Active Direct Box Specifications

• Technical Specs:
  • Audio Circuit Type: Proprietary analog circuit with low-noise op-amp
  • Frequency Response: 20Hz ~ 20kHz
  • Dynamic Range: 109dB
  • Noise Floor: -99dB below 0dBu
  • Equivalent Input Noise: -103dBu
  • Maximum Input: +10dBu
  • Phase Deviation: +10º at 20Hz | 0º at 1kHz | -1º at 20kHz
  • Total Harmonic Distortion: 0.002% @ -5dBu
  • Inter-modulation Distortion: 0.003% @ -3dBu
  • Input Impedance: 220k? - ¼" input
  • Output Impedance: 600? - XLR output
• Features:
  • Input Connectors: Dual 1/4" in and thru jacks
  • Input Pad: -15dB
  • Polarity: 180º signal polarity reverse switch
  • High Pass Filter (HPF): -3dB @ 80Hz
  • Ground Lift: Disconnects pin-1 at XLR output
  • XLR Output: Follows AES standard (pin-2 hot)
• General:
  • Power: 48V phantom - proprietary digital switching
  • Construction: 14 gauge steel chassis and outer shell
  • Finish: Durable powder coat
  • Size: 3.3" x 5.0" x 2" (84 x 127 x 48mm)
  • Weight: 1.55 lb (720 g)
  • FCC Approval: Complies with section 15 of the FCC Rules
  • Conditions: For use in dry locations only between 5°C and 40°C

Radial J48 Stereo Active Direct Box Includes

• Radial J48 Stereo Active Direct Box
• User Guide
• 3 Year Warranty