Radial Engineering JDV Mk5 User manual

True to the Music
www.radialeng.com
®
True to the Music
®
User Guide
JDV Mk5
Active Direct Box
www.radialeng.com
Radial Engineering Ltd.
1588 Kebet Way, Port Coquitlam
British Columbia, Canada, V3C 5M5
tel: [phone] • fax: [phone]
email: [email protected]
™

JDV™ Mk5 Active Direct Box
True to the Music
®
Radial Engineering Ltd.
Radial JDV Mk5
Active Direct Box
™
®
Table of Contents Page
Feature set ..............................................................................................................1-2
Overview.....................................................................................................................3
Pickup or instrument source options ..........................................................................4
Making connections.................................................................................................5-6
Selecting channels .....................................................................................................7
Using the JDV.............................................................................................................8
Blending the two channels..........................................................................................9
Setting the output controls........................................................................................ 10
Rackmounting kit...................................................................................................... 11
Specications ........................................................................................................... 11
Block diagram........................................................................................................... 12
Warranty .................................................................................................... Back Cover
Thank you for purchasing the Radial JDV Mk5 Super DI. We are condent that you will nd
it to be one of the most enjoyable pieces of equipment you will ever use and it will likely
become a mainstay for all of your recordings and live gigs.
This next generation JDV retains the natural tone of the original while adding many new
features that will enhance the performance and open up creative new options. Before you get
started please take a few minutes to read through this manual. Inside you will discover why
certain features have been implemented which in turn will make using the JDV a lot more fun.
If after you have read the manual, you nd yourself asking questions... please visit the FAQ
page on the JDV web site. This is where we post questions from users and the latest updates.
If you do not nd what you are looking for, please send an email to [email protected] and
we will do our very best to reply to you in short order.
Now get ready to experience natural sound like never before!

Radial Engineering Ltd. JDV™ Mk5 Active Direct Box
True to the Music
®
FRONT PANEL FEATURE SET
1
1. LEVEL A: Fully variable control, used to set the input sensitivity for channel-A.
2. ON/10M: Sets the load to 10MΩ for piezo or variable drag for magnetic pickups.
3. DRAG: Used to retain the natural feel of the instrument by adjusting the load for
passive pickups.
4. 48V: LED Indicator lets you know 48V phantom power is activated on the MIC IN.
5. HPF: Variable high-pass  lter rolls off low frequency resonance that can cause
feedback or muddy up the sound.
6. AB: Channel selector toggles between A and B inputs with LED status indicators.
7. LEVEL B: Fully variable control, used to set the input sensitivity for channel-B.
8. LOAD: Switches the input impedance from 10MΩ for piezo transducers to 220kΩ for
magnetic pickups.
9. SIG/OVD: LEDs show signal presence and if you are exceeding the maximum input level.
10. PHAZER: Adjusts the relative phase between channel A and B to time align
fundamentals for a more natural sound.
11. 0/180º: Shifts the Phazer's range from 1º~180ºto 181º~360º.
1
12 13 14
7 82 43 9 10 11
A
A
5 6
12. MIC 48V: Turns on the 48V phantom power at the MIC IN.
13. BLEND: Combines input-A with input-B and lets you mix the
two sources using the front panel level controls.
14. AUX OUT/DIRECT: Lets you introduce an isolation transformer
into the stage amp output signal path to reduce hum and buzz
caused by ground loops.

JDV™ Mk5 Active Direct Box
True to the Music
®
Radial Engineering Ltd.
REAR PANEL FEATURE SET
2
15 16 17 19 20 21 22 23 24 2518
15. POWER: Locking 4-pin XLR connection for the external power supply.
16. OUTPUT: Balanced XLR output connects to the PA or recording system. Transformer
isolated to eliminate hum & buzz caused by ground loops.
17. 180º POLARITY: Inverts the signal polarity by fl ipping pins-2 and pin-3 on the XLR
output. Used to reduce resonant peaks that cause feedback.
18. GROUND LIFT: Disconnects pin-1 at the XLR out to reduce hum and buzz caused by
ground loops.
19. ISO: Introduces an isolation transformer into the XLR signal path to help eliminate hum
and buzz caused by ground loops.
20. +20dB: Increased output to line level for direct recording.
21. TUNER OUT: Always-on, hi-Z output used to connect an electronic tuner.
22. JR•2: For optional JR•2 remote footswitch. When connected, this lets you select the
input channel or mute the JDV for silent tuning.
23. THRU: Unbalanced ¼" thru-put used to feed the stage amp.
24. MIC IN: Balanced ¼” TRS input for condensor or dynamic microphone.
25. INPUTS A & B: Unbalanced ¼” input jacks used to connect instruments to the JDV.

Radial Engineering Ltd. JDV™ Mk5 Active Direct Box
True to the Music
®
3
OVERVIEW
The Radial JDV is more than a direct box. It is a dual input DI box, mic preamp, two-channel
mixer and phase adjustment tool all in one. This means it can be used for all types of instru-
ments including:
What is particularly cool about the JDV is that it packs all of this in a relatively small box.
This means that you have to start by understanding the many features and then apply them
according to how you intend to use it.
There are two inputs and one output. You can set each input to suit a particular instrument
and then send the unbalanced output to a stage amp, while sending the balanced signal to a
recording workstation or PA system. You can switch between the inputs using the front panel
switch or via an optional remote footswitch. You also have the option of blending both chan-
nels together so that they play simultaneously.
• Passive electric bass with magnetic pickup
• Active electric bass with built-in preamp
• Acoustic guitar with built-in preamp
• Piezo equipped upright bass
• As a microphone preamp for an instrument mounted mic
• For direct recording or live performance
• Any combination thereof

JDV™ Mk5 Active Direct Box
True to the Music
®
Radial Engineering Ltd.
4
PICKUP OR INSTRUMENT SOURCE OPTIONS
If you review all of the various instrument pickups or music sources that are in use today,
one can actually break them down to ve major categories. The JDV is designed to accom-
modate all of them.
Magnetic pickup
This is the most common type of pickup found on a Gibson®
Les Paul electric guitar or Fender® Jazz bass. To accommo-
date them, the JDV is equipped with Drag™ control load cor-
rection. This lets you adjust the load from 1MΩdown to 10kΩ
to set the tone as if connected directly to a tube amplier. Set
the Drag control to 12 o’clock and then adjust to suit.
Buffered instrument
A buffer is basically a unity gain amplier. An active bass or
acoustic guitar with built in electronics can be grouped into
a category called a buffered source. These – usually battery
operated devices – produce a louder signal than a passive
magnetic pickup. Since they are already amplied, chang-
ing the load using the Drag control will have very little effect.
However, you can reduce the suceptibility by lowering the input
impedance by rotating the Drag control fully counter-clockwise.
Piezo transducer
For years artists and engineers have complained that piezo
pickups tend to sound harsh and peaky. During the develop-
ment of the Radial Tonebone PZ-Pre™, we discovered that
by elevating the impedance, you can dramatically widen the
frequency response and smooth out the tone. Like the PZ-Pre,
the JDV sports a 10MΩ option for piezos that extends the re-
sponse so well we actually had to incorporate high-pass lters
to control the excessive bottom end! The lter is particularly
effective at ‘sizing’ the instrument so that when you connect an
acoustic guitar or a mandolin, you can set the lter so that it coincides with the instrument in use.
Line level instrument
Although connecting a high output keyboard or drum machine to the JDV is somewhat over
the top, it will occasionally occur. This is where the internal rail voltage will come in handy.
Unlike most direct boxes that have a rail voltage of about 3 to 5 volts, the JDV is able to handle
signal levels in excess of 16 volts!
Microphone
Many acoustic musicians use a clip-on microphone to capture nuances that may be lost when
using a magnetic pickup. The JDV is equipped with a balanced input that may be used with a
dynamic or a condensor mic by activating the 48V phantom power. As a safety measure, the
48V phantom power must be turned on each time the JDV is being used.
As you gain familiarity with the JDV, you will discover that the channel-A feature set is slightly
different than channel-B so you can use any of the above, in whatever combination works
best for you.

Radial Engineering Ltd. JDV™ Mk5 Active Direct Box
True to the Music
®
5
MAKING CONNECTIONS
Before making connections always ensure levels are turned down or audio
systems turned off. This will avoid connection or turn-on transients that
could harm sensitive components such as the tweeters in your speaker
system. There is no power switch on the JDV. As soon as you plug in the
power supply the JDV will come to life. The JDV’s external power supply
will accommodate any voltage from 100V to 240V. Simply change the IEC
cable to suit. The 4-pin XLR provides a secure locking connection. Before disconnecting,
once again make sure the equipment that is connected is powered off or levels turned down.
As there are many connection options, we will use a simple bass guitar as the working example.
The same basic approach will work for most instruments. Begin by setting all of the controls
and switches in the start position as shown below.
Connect your instrument to input-A using a standard ¼” coaxial guitar cable and the XLR
output to a mic input on your mixing console. The balanced XLR male output employs the
AES standard with pin-1 ground, pin-2 hot (+) and pin-3 cold (-). Check to make sure the AB
selector is set to A (in the "out" position). Set the level control on the JDV to 12 o’clock and
increase the mixer volume until you reach a comfortable listening level. Always test at low
volumes to prevent damage to components should a connection be loose. If you like, connect
your stage amp using the THRU output. This buffered output is used to send the active signal
to the stage amp or effects pedals.
OFF
(OUT)
CHANNEL A
(OUT)
220K
(OUT)
OFF
(OUT)

JDV™ Mk5 Active Direct Box
True to the Music
®
Radial Engineering Ltd.
6
Using piezo transducers
In order to provide maximum fl exibility, both channels A and B are equipped with 10MΩinputs
for piezos. This enables two piezos to be used at once, a magnetic pickup with a piezo, a
mic with a piezo or any combination of the above. The bene t here is that you do not have
to use a secondary piezo preamp, simply connect directly to the JDV and it will work great.
Using a microphone with the JDV
Channel-1 on the JDV is equipped with a dedicated ¼” TRS balance mic input. Due to limited
space, this is unfortunately not a standard XLR. The good news is that music stores carry
XLR-F to ¼” TRS cables as a standard offering. Once connected, this switching jack will
automatically turn off the guitar inputs.
Since most instrument-mounted microphones are condensers, they generally require 48-volt
phantom power. The JDV is equipped with 48V phantom on channel-A. To turn on the phantom
power, simply depress the side access set & forget switch.
Caution! If you mistakenly connect your
pickup to the mic input when phantom
power is activated, it can seriously dam-
age your pickup. For this reason, the JDV
is equipped with a preventative measure
that requires turning on the phantom power
each time you power-on the JDV. To avoid
a loud pop always turn PA/amp levels off
before turning on phantom power.
¼” TRS
XLR-F

Radial Engineering Ltd. JDV™ Mk5 Active Direct Box
True to the Music
®
7
JR•2 remote footswitch
For quiet tuning on stage you can mute the JDV output using the optional
JR•2 footswitch. Two footswitches are on board to allow AB switching
and mute. When muted, the front panel MUTE LED will illuminate as
will the footswitch mute LED. When muted, all of the JDV outputs other
than the tuner will be turned off. The JR•2 may be connected using
either a TRS-TRS or TRS-XLR cable.
¼” TRS to TRS XLR-F to TRS
SELECTING CHANNELS
Using the AB select switch
You can now connect your second bass to input-B. To switch, simply depress the front panel
SELECT switch. You can also toggle the input by using the optional JR•2 footswitch. When
connected, the JR•2 derives its power from the JDV to illuminate the status LEDs. When
depressed, both the LEDs on the JR•2 and on the JDV front panel will follow suit. Set the
Channel-B level control to 12 o’clock and then switch back and forth between the two instru-
ments and adjust the levels so that they are relatively even in loudness.
Channel-A
Select
Channel-B
Select
Connect an electronic tuner
The JDV is equipped with a dedicated ¼” tuner output that is always on. This is separately
buffered so that the internal quartz clock will not introduce noise into the JDV or the audio
system. This output can also be used to feed a second amp.

JDV™ Mk5 Active Direct Box
True to the Music
®
Radial Engineering Ltd.
8
USING THE JDV
Adjusting the DRAG Control
When you connect your bass to the JDV the signal will be buffered by a
unity gain ampli er. This can brighten your tone and enable much longer
cables (upwards to 15 meters or 50’) to be used without noise. Drag™ is
a load correction circuit that enables the user to replicate the tone and
feel as if connected directly to your amp using a regular 15' guitar cable.
To activate the DRAG control, push the set & forget switch inward. Start
by setting the Drag control to 12 o’clock and rotate it clockwise. You will
note the tone will become brighter. Now try turning it counter-clockwise
to darken the tone. Adjust to suit. Drag control has little effect on an
active bass or acoustic guitar with built-in electronics as the signal is
pre-buffered by the electronics inside the instrument.
When set in the outward position, the DRAG control is turned off and the input impedance
rises to 10MΩ to suit piezo transducers.
Using the high-pass fi lter
One of the most practical functions on the JDV is the high-pass  lter
(HPF). This fully variable control lets you adjust the cut-off point or low
frequency limit to eliminate resonance. What few realize is that by re-
ducing excessive low frequencies, instruments will  t more naturally into
the mix, enabling their levels to be louder without competing as much
for bandwidth. This ‘Nashville trick’ has been used for years to combine
various acoustic instruments such as upright bass, acoustic guitar, banjo,
 ddle and mandolin by sizing the instrument to suit.
Start by rotating the  lter clockwise until the low frequency cut-off
becomes audible. Then back off the control slightly. This will not only
clean up your mix, but also help eliminate weird modulations that can
creep into recordings.
When using two sources simultaneously, listen to each one individually as you adjust the low
frequency cut-off point and then remix the two channels (sources) to suit.
OFF
LOW CUT
MAX
LOW CUT
OFF MAX
LOW CUT
OFF MAX
LOW CUT
OFF MAX
LOW CUT
OFF MAX
LOW CUT
OFF MAX
LOW CUT

Radial Engineering Ltd. JDV™ Mk5 Active Direct Box
True to the Music
®
9
Using the Phazer
Combining two pickups or a mic with a pickup can often produce much
more realistic sounds than using a mic or pickup alone. Things really start
to shine when you combine the two sources using the BLEND function
and then introduce the PHAZER™ into the equation.
The Phazer is an analogue phase adjustment tool that is applied to
the primary source or that closest to the originating sound. This is then
‘fractionally delayed’ to time-align the fundamental frequencies so that
they play in phase.
Start by setting up two sources on a single instrument and set the relative volumes to the
same level. Keep in mind that if you use a mic, any movement or altering the distance of the
mic from the sound hole will change the relative phase and loudness. So you either have to
carefully remain in one place relative to the mic or use an instrument-mounted microphone
that will move with the instrument.
Set the phase control fully counter-clockwise. Activate the Phazer by pushing in the switch.
Now have someone rotate the control as you play. Altering the relative level between the mic
and pickup dramatically alter the tone of the instrument. Try changing the range using the
slider switch. Have fun. Note that there is no perfect setup. Phase is relative and cannot be
anticipated. Simply use your ears to  nd the most pleasing sound.
A - Condensor Mic
B - Pick up
Night
Phase Shift
Crest
0° 90° 180° 270° 360°
Amplitude
0dB
Time
Trough
Wave Length
Wave Cycle
Phase Corrected
A
B
Night
Phase Shift
Crest
0° 90° 180° 270° 360°
Amplitude
0dB
Time
Trough
Wave Length
Wave Cycle
Phase Corrected
A
B
BLENDING THE TWO CHANNELS
The JDV is also equipped with a BLEND function on the side
panel that allows both channels to be active at the same time.
This can be used to combine a piezo and a magnetic pickup
on an acoustic guitar, a mic and a piezo on a bass or to simply
have two instruments on all the time for practicality sake. The
BLEND is activated by depressing the set & forget switch
inward. You may  nd a slight drop in volume due to the mixing
process. Simply adjust the input level controls to compensate.

JDV™ Mk5 Active Direct Box
True to the Music
®
Radial Engineering Ltd.
10
SETTING THE OUTPUT CONTROLS
Using the 180° polarity reverse
The JDV is equipped with a 180° polarity reverse that
toggles pin-2 and pin-3 on the XLR output. This func-
tion was originally intended to connect older vintage
equipment that did not employ the AES standard with
new gear.
This handy switch can also perform other various func-
tions. When used with an electric bass in a small venue,
reversing the polarity can be used to better align low
frequencies from the on-stage bass amp with the PA
system. When used with an acoustic instrument, it can be used to alleviate feedback without
reverting to dramatic EQ curves. When sound from the PA system, the on-stage amp, moni-
tors and the venue itself combine, huge frequency bumps that can cause resonant feedback
or phase cancellation will often occur. Reversing the polarity on the JDV can often move the
problem out of the way.
Lifting the ground and isolating the output
If you encounter hum or buzz, you can lift the ground on the XLR output by depressing
the ground lift switch. This is recessed in order to prevent accidental use when reaching in
behind the JDV. Use a small screwdriver to depress the switch.
You can also address noise problems by introducing an isolation transformer to the signal
path. The XLR output can be isolated via the rear panel switch, and the AUX output via the
side panel switch. It is good practice to employ a power bar to connect all of your amps, ef-
fects and the JDV so that they share the same electrical ground.
Try isolating the XLR  rst, as this will disconnect the audio ground between the stage and
the PA or recording system. If you still hear hum, try reconnecting the XLR ground and then
isolating the AUX output. Ground problems can crop up for all kinds of reasons. Simply take
your time to try the various combinations until the noise goes away.
+20dB for direct recording
When recording direct, some players perfer to take the sound right off the JDV instead of
going through a mic preamp. Depress the +20dB switch to increase the JDV output from mic
level to line level.

Radial Engineering Ltd. JDV™ Mk5 Active Direct Box
True to the Music
®
11
Frequency response................................................................. 30Hz ~ 20KHz
Gain (instrument input)............................................................. +25 dB
Gain (line level boost)............................................................... +20 dB
Gain (microphone input)........................................................... +25 dB
Dynamic range ......................................................................... 107dB
Equivalent input noise .............................................................. -90 dBu
Input impedance ...................................................................... 22k to 500k Drag on - 1/4” input: 10M Drag off
Output impedance at XLR ........................................................ 400 Ohms
Low-cut lter: ............................................................................ Variable from 25Hz ~ 500Hz (-3dB point)
Size (W, D, H) & weight............................................................ 5.75” x 8.25” x 1.75” (2.75” with handle)
146mm x 210mm x 45mm (70mm with handle)
Weight ...................................................................................... 3.95lbs. (1.80kg)
Power supply............................................................................ +/-16v (1600mA) 5-pin XLR power supply
*Specications are subject to change without notice.
SPECIFICATIONS
RACK MOUNTING THE JDV
For touring the JDV may be mounted into a standard 19” rack using the optional rack mount
kit. This three piece kit (part number: R800 2020 02) enables one or two JDV to be rack
mounted in a 1RU rack space.
Single unit mounting: Double unit mounting:

JDV™ Mk5 Active Direct Box
True to the Music
®
Radial Engineering Ltd.
12
BLOCK DIAGRAM
BLEND

www.radialeng.com
THREE YEAR TRANSFERABLE LIMITED WARRANTY
RADIAL ENGINEERING LTD. (“Radial”) warrants this product to be free
from defects in material and workmanship and will remedy any such de-
fects free of charge according to the terms of this warranty. Radial will
repair or replace (at its option) any defective component(s) of this product
(excluding  nish and wear and tear on components under normal use) for
a period of three (3) years from the original date of purchase. In the event
that a particular product is no longer available, Radial reserves the right
to replace the product with a similar product of equal or greater value. In
the unlikely event that a defect is uncovered, please call 604-942-1001
or email [email protected] to obtain an RA number (Return Autho-
rization number) before the 3 year warranty period expires. The product
must be returned prepaid in the original shipping container (or equivalent)
to Radial or to an authorized Radial repair center and you must assume
the risk of loss or damage. A copy of the original invoice showing date of
purchase and the dealer name must accompany any request for work to
be performed under this limited and transferable warranty. This warranty
shall not apply if the product has been damaged due to abuse, misuse,
misapplication, accident or as a result of service or modi cation by any
other than an authorized Radial repair center.
THERE ARE NO EXPRESSED WARRANTIES OTHER THAN THOSE
ON THE FACE HEREOF AND DESCRIBED ABOVE. NO WARRANTIES
WHETHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMIT-
ED TO, ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FIT-
NESS FOR A PARTICULAR PURPOSE SHALL EXTEND BEYOND THE
RESPECTIVE WARRANTY PERIOD DESCRIBED ABOVE OF THREE
YEARS. RADIAL SHALL NOT BE RESPONSIBLE OR LIABLE FOR ANY
SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LOSS
ARISING FROM THE USE OF THIS PRODUCT. THIS WARRANTY
GIVES YOU SPECIFIC LEGAL RIGHTS, AND YOU MAY ALSO HAVE
OTHER RIGHTS, WHICH MAY VARY DEPENDING ON WHERE YOU
LIVE AND WHERE THE PRODUCT WAS PURCHASED.
Radial®JDV™Mk5 User Guide - Part #R870 1005 10
Speci cations and appearance are subject to change without notice.
Radial Engineering Ltd.
1588 Kebet Way, Port Coquitlam BC V3C 5M5
tel: [phone] • fax: [phone]
[email protected] • www.radialeng.com