J48™ Specifications

The Radial J48 has gained a tremendous following through the professional audio community. With significantly more headroom, lower distortion and unmatched durability, it is no wonder that the J48 has become the most specified direct box on stages around the world. As you will note with the specifications below, the J48 is exceptionally linear when tested both under laboratory conditions and when placed under the extra stress of 100 meters (300 feet) of cable. In the lab, the high frequency response actually exceeds 40kHz! This makes the J48 a perfect candidate for the most demanding studio recording while being the obvious choice for the artist on stage.

Radial J48 Block Diagram

Radial J48 Block Diagram
Radial Blue Report
The Radial Blue Report
In effort to provide the more discerning audio engineer with all of the technical support materials to make a proper and informed decision, we have produced the Radial Blue Report. This provides in-depth distortion tests and analysis of four popular direct boxes....

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Specifications  
Specifications are subject to change without notice.
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: 220kΩ - ¼" input
Output impedance: 200Ω - XLR output
Features  
Merge function: IN and THRU jacks are summed to mono
Input pad: -15dB
Polarity: 180º signal polarity reverse switch
Low-cut filter: -3 dB @ 80Hz
Ground lift: Disconnects pin-1 at XLR output
XLR configuration: 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
Warranty: Radial 3-year, transferable
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Radial J48 FFT
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