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True to the Music ™ Radial Engineering Ltd. Passive Direct Box 1845 Kingsway Ave., Port Coquitlam, BC V3C 1S9, Canada Tel: 604-942-1001 • Fax: 604-942-1010 User Guide Email: info@radialeng.com...
The Radial JDI is the latest version of the highly acclaimed JDI and is without a doubt the finest passive direct box available today. The JDI is very unique in that it does not color or alter the sound in any way. This ensures that natural tone and harmonic balance is retained, bringing out the very essence of the instrument.
True to the Music Part 2 – The JDI Feature Set (8) Double sided PC board - military grade circuit board (1) 15dB PAD switch - a -15dB pad can be introduced to features a full ground plane for maximum protection reduce the input voltage and ensure a clean, distortion- against stray magnetic fields and RF noise.
–15dB pad should be used to reduce the input level to the transformer. If you hear distortion, simply depress the –15dB pad button. If you intend to use the JDI in parallel with a speaker load, it is important that you read the details on this application in the ‘Part 5 - Features and Functions’...
Balanced signals inherently cancel noise and due to their lower impedance, can travel much further without degradation. Balanced signals are the norm in professional recording, broadcast and live sound. By properly matching the impedance you will enjoy better sound, less noise and an extended frequency response. Radial Engineering User Guide ™...
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XLR output, it is converted to a balanced 150 Ohm low impedance signal. This allows long cable runs without introducing noise into the audio signal path. It is important to note that the output of the Radial JDI is a mic level signal. This allows the JDI to be used along side other microphone signals without introducing cross-talk or causing transformer saturation when driving the signal through the mic bridging transformers of a splitter.
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1kHz, but as the frequency dropped, the ‘ugly truth’ started to appear. One popularly used DI was almost 20º out of phase at 20Hz while another was almost 40º out of phase! The JDI tested at less than 4º off the mark, making it the most phase accurate DI on the planet.
The ¼” INPUT and THRU connectors out to mixer The JDI features two ¼” jacks on the input panel. These are designed to accept instrument inputs from basses, guitars, keyboards, drum machines, etc. The left ¼” input jack is normally connected to the source instrument.
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The JDI is designed to handle these signal levels without fear of overloading and is one of the main advantages you will enjoy with your JDI. However, you may occasionally encounter devices with extremely high output levels such as from CD players, a mixer output or even a headphone out that can overdrive the circuit or saturate the transformer.
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Note that when you are ‘going direct’ by connecting a bass or acoustic guitar to the Radial JDI without using the thru-put, the ground switch should be set in the outward position so that the JDI is grounded at the mixing console. If you are using the thru-put to your personal amp, then your amp and the mixer will have ground paths and lifting the ground would then be considered.
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The JDI's parallel speaker connection feature lets you do this by connecting the JDI directly to the speaker cabinet. It is important to note that the JDI is NOT a load box; you must have a load such as a speaker connected to the amplifier, as connecting the JDI directly without a load could cause severe damage to the equipment.
The Radial JDI can be used ‘backwards’ to convert a low-impedance mic level signal back to a high-impedance guitar signal. Simply connect the output from the recorder to a mixer and the mixer's output to the JDI's XLR output using a female-to- female XLR turn-around adaptor.
Passive direct boxes are often chosen as they are ‘plug & play’ easy to use. When equipped with a high quality transformer, they can handle exceptionally high signal levels without harmonic distortion and a good one like the JDI will process the signal without introducing artifacts such as phase distortion.
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DIs' performed at 20Hz. One popular direct box was 40º out of phase, while another was 20º out! The Radial JDI tested at less than 4º. We spend thousands of dollars on PA systems to ensure they are time...
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Q: If my JDI ever fails, what do I do? A: In the past 10 years the JDI has been so reliable that it is a rare occurrence when we need to repair one. If however something goes bad, a switch for example, simply call Radial and we will issue a return authorization number for you to send it back to us for repair.