Radial JDI – Jensen Equipped 1-channel Passive Instrument Direct Box

The Radial JDI passive direct box is the kind of premium-quality direct tool you need for great sound and rock-solid reliability on stages and studios anywhere. The Radial JDI features a Jensen isolation transformer to give you the best performance possible at all frequencies. This box can handle very high signal levels without distorting, and its passive design helps to eliminate 60-cycle ground loops. Great for everything from passive and active guitars and basses to analog and digital keyboards, the Radial JDI is a dependable, quality performer!

Radial JDI at a Glance:

• Jensen transformer-equipped passive DI
• 100% isolation eliminates ground loops
• Virtually zero phase & harmonic distortion
• Exceptional signal handling
• High common mode noise rejection
• Welded I-beam construction

Jensen transformer for optimum performance

The JDI’s Jensen transformer is the product of decades of experience in transformer production. This transformer delivers optimum audio performance offering outstanding linearity at all frequencies, combined with extraordinary level handling without introducing distortion.

The input panel features a 1/4″ instrument input and traditional thru-put. An innovative ‘merge’ function allows the thru-put to be converted to a second input to allow stereo to mono summing. This is often used to interface stereo sources such as keyboards or CD players in live shows where audio channels may be not always be plentiful. The JDI also sports a -15dB pad to interface with higher output levels.

The JDI’s output panel features balanced 600-ohm XLR connector with pin-2 hot following the AES specification. A polarity reverse switch toggles pin-2 and pin-3 to allow the JDI to interface with older non-AES equipment and for creative tinkering. The ground lift switch disconnects the XLR pin-1 ground from the JDI for 100% input-to-output isolation.

Finally, a second -30dB pad may be engaged that, when used in tandem with the -15dB input pad, allows the JDI to be connected in parallel with a speaker. This, for instance, allows the engineer to ‘tap’ the sound coming from a guitar amplifier speaker ‘post distortion’ thus adding another creative dimension. This unique function incorporates a speaker emulation filter circuit that rolls off highs and lows to more closely approximate the sound of a 12″ driver.

Construction

As with all Radial direct box, the Radial JDI is designed for use in abusive environments such as on fast-paced stages of concert touring. An innovative book-end design provides a protective zone around the switches and connectors that makes it practically impossible to damage these components.

The inner skeletal frame features a unique 14-gauge welded I-beam construction that makes it impossible to torque the PC board. Stress on the printed circuit board can introduce intermittent solder joints, which by all accounts is the primary cause of direct box failure.

An innovative full-bottom no-slip rubberized pad works double duty by assuring the J48 won’t slip and slide around when placed on an amplifier. The protective pad also ads an element of electrical shock resistance by providing a mechanical shield from guitar amp handles that are often directly coupled to the amp chassis.

Radial JDI Features:

• Welded I-beam construction makes it impossible to torque the PC board. This virtually eliminates cold solder joints – the No.1 cause of system failure in the field.
• An innovative ‘slide-in-place’ XLR trace makes it possible to use I-Beam girder construction.
• Jensen transformer for distortion-free performance.
• A military-grade PC board is employed for maximum wear and tear in abusive environments. Welded steel standoffs ensure the PC board will not shift.
• A -15dB pad allows super hot inputs such as that from a CD player to be connected and balanced for long runs.
• The Merge function turns the input and thru into a passive mixer to sum stereo feeds to mono at the XLR output. This saves valuable inputs on the mixer!
• The input connects to the instrument.
• The thru-put is connected to the instrument amplifier. The JDI has a high input impedance to reduce loading.
• Book-end design creates a protective zone around the switches & connectors for best protection!
• A heavy-duty baked enamel finish for excellent durability and great looks for years! 100% 14-gauge steel construction.
• The XLR balanced mic level output provides 100% isolation for runs to 1000 feet without appreciable noise.
• A polarity reverse switch flips the polarity from the AES standard Pin-2 to Pin-3 on the XLR and is used when combining sounds that may be out of phase.
• The ground-lift disconnects the ground path to the transformer at the XLR output. This is used when a ground path is made at the input side such as with a keyboard.
• The parallel speaker interface option introduces a second -30dB pad with band-pass filter to emulate a 12″ guitar speaker.
• A no-slip full bottom pad reduces mechanical vibration, improves electrical isolation and keeps the JDI from moving around on busy stages!

Why Buy From Marshall Music

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