Radial Engineering PZ-DI User manual

TruetotheMusic
Radial Engineering Ltd.
1588 Kebet Way, Port Coquitlam BC V3C 5M5
Tel: [phone] Fax: [phone]
email: [email protected]
www.tonebone.com
PZ-DI™
Acoustic/Electric
PickupSelector,
BufferandDirectBox
UserGuide

TruetotheMusic
Radial Engineering Ltd. PZ-DI™User Guide
www.radialeng.com
Congratulations on your purchase of the Radial PZ-DI. The PZ-
DI is a truly unique product that enables you to select between
themagnetic pickup andpiezoacoustic transducer onyour guitar
for quick on-stage transitions without having to take your hands
off the fingerboard. Hopefully, this will open doors to creative
new ways to use your guitar which in turn will spur on exciting
new musical ideas.
In developing the PZ-DI, we have incorporated flexibility both at
the input and the output. You will find the signal routing to be ef-
ficient and quiet while delivering the most natural tone. And like
all Tonebone pedals, the PZ-Pre is designed to be ‘plug & play’
easy to use. But as with any product, taking the time to read
through the manual will unlock secrets that we know will help
deliver the very best results. So please take a minute to give this
document a read.
If you have any questions feel free to send us a note at
[email protected] and we will do our very best to get back to
you promptly. You should also consult the FAQ section on the
web page as this is where we post the latest notes, questions
and updates.
Now get ready to bring both matter and anti-matter together in
perfect harmony!
Radial Engineering Ltd.
RadialPZ-DI™
AcousticInstrumentPreamp
UserGuide
Table of Contents Page
Introduction.................................................................. 1
Feature Set.................................................................. 2
System Setup.............................................................. 3
Using the PZ-DI........................................................... 4
Using The PZ-DI With Two Instruments...................... 6
Using The PZ-DI With Effects...................................... 7
Frequently Asked Questions ....................................... 8
Block Diagram.......................................................4 & 9
Specifcations............................................................... 9
Warranty................................................................Back Cover
1

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Radial Engineering Ltd. PZ-DI™User Guide
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1. POWER SUPPLY (15VDC-400mA): connection for the
included 15 volt DC, center pin positive power supply. Use
only with Radial power supply #R800-9407.
2. EFFECTS LOOP (PIEZO CHANNEL): ¼” TRS insert jack
allows effect pedals to be placed in the acoustic piezo signal
path. (Tip=Send / Ring=Return)
3. BALANCED DI OUT: balanced mic-level XLR output sends
acoustic piezo signal to the PA or recording system.
4. TUNER OUT: buffered and always on ¼” output sends
magnetic and piezo pickup signals to an electronic tuner.
5. DRAG CONTROL: recessed control adjusts the amount of
load on the magnetic pickup. Full clockwise is max input
impedance (approximately 1MegaOhm) and produces a
bright tone. Turning counter-clockwise will increase the load
on the pickup and darken the tone.
6. ELECTRICPICKUPINPUT: ¼” inputfor the guitarsmagnetic
pickup.
7. ACOUSTIC PIEZO INPUT: ¼” input for the guitars acoustic
piezo pickup. NOTE: This input may also be fed from the
electric input jack by using a TRS (Tip Ring Sleve) ¼” phone
jack where the ring conducts the acoustic pickup.
8. ACOUSTIC PIEZO FOOTSWITCH: used to activate the
guitars acoustic piezo pickup channel.
9. ELECTRIC PICKUP FOOTSWITCH: used to activate the
guitars magnetic pickups channel. NOTE: Both PZ-DI
channels and pickups may be active at the same time.
10. ACOUSTIC PIEZO OUT: ¼” output connects the acoustic
piezo pickup to the on-stage acoustic amplifier. This output
is transformer isolated to block ground loops between your
electric and acoustic amplifiers.
11. ELECTRIC PICKUP OUT: ¼” output connects the magnetic
pickup signal to the on-stage amplifier.
FEATURES AND FUNCTIONS
10
11
9 8
1 2 4 53
6
7

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Radial Engineering Ltd. PZ-DI™User Guide
3
PIEZO CHANNEL CONTROL SECTION
12 13 14 15 16
12. ¼” GROUNDLIFT: disconnectsthe ground connection at the
ACOUSTICPIEZO¼”outputtoreducehumandbuzzcaused
by ground loop between amplifiers.
13. XLR GROUND LIFT: disconnects the pin-1 ground connection on
the XLR output to reduce hum and buzz caused by ground loops.
14. XLR 180º POLARITY: reverses signal polarity at the XLR
output to help with phase and feedback problems.
15. LO-CUT FILTER: three position switch removes low
frequencies from the acoustic piezo signal.
Position 1 = Flat (bypassed).
Position 2 = Cuts low frequencies below 75Hz.
Position 3 = Cuts low-mid frequencies below 220Hz.
16. HI-CUT FILTER: three position switch removes high
frequencies from the acoustic piezo signal.
Position 1 = Flat (bypassed).
Position 2 = Cuts high frequencies above 2.8kHz.
Position 3 = Cuts very high frequencies above 7.2kHz.
TYPICAL SYSTEM SETUP

TruetotheMusic
Radial Engineering Ltd. PZ-DI™User Guide
USING THE PZ-DI
The Radial PZ-DI is pretty much ‘plug and play’ easy to use.
There are only a few little extras that one needs to be aware of to
take full advantage of the PZ-DI’s feature set.The easiest way to
understand the PZ-DI is to follow the basic block diagram:
Therearetwoinputseachofwhichdrivesaseparatechannel:one
for the magnetic (electric pickup) and one for the piezo (acoustic
pickup). Because both of these sources are very different, they
are treated individually to maximize performance.
Making Connections
As with any audio system, always make your connections with
your equipment turned off or levels set to zero. This will avoid
transients that can damage speakers. There is no power switch
on the PZ-DI. As soon as you connect the 15VDC power supply
it will turn on. To check powering, simply depress one of the two
footswitches and the LED indicator will illuminate.
Most combination magnetic-piezo guitars have either stereo ¼”
TRS output or are equipped with separate ¼” outputs for each
pickup type. When you connect to the PZ-DI with a TRS cable,
the tip of the connector feeds the electric channel and the ring
feeds the acoustic. If your guitar is not set up this way, you simply
need to reverse the connections at the output end of your cable
to accommodate. The PZ-DI will break out each signal internally
and send it to the appropriate channel.
4

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Radial Engineering Ltd. PZ-DI™User Guide
5
The Magnetic Electric
Start by connecting the electric guitar amp using a standard ¼”
cable. Turn the amp on, turn up the volume a bit and test to make
sure it works by depressing the electric footswitch. The LED on
the PZ-DI should illuminate and you should hear sound.
To keep the purist happy, the magnetic (electric pickup) signal
pathhasbeenpurposelykeptextremelyclean.Wehaveemployed
Radial’sawardwinningclass-Abufferingcircuitand Drag Control
load correction to ensure a natural sounding, noise free connec-
tion is delivered to your amp. Set the Drag Control to 12 o’clock
using a guitar pick as a screwdriver. This ‘set & forget’ control
is recessed so that once you have decided on where you like it
- your setting will not accidentally get changed.
DragControl reintroduces theload on thepickup to replicatehow
the guitar sounds when connected directly to a tube (valve) amp
through a length of cable. Because the PZ-DI is buffered, the
signal will likely be too clean if set to full. The 12 o’clock position
replicates the sound of a Fender Stratocaster® connected to a
tube amp. Try it, it will blow you away.
The Piezo Acoustic
For the piezo (acoustic pickup) source, you actually have two
outputs to choose from: the stage amp and the direct box. Start
by connecting the stage amplifier following the same process
as described previously. Testing the signal is merely a matter
of depressing the footswitch, checking the LED to make sure it
goes on and then turning up your amp. The piezo output is also
transformercoupled so thatit can beelectrically isolated fromthe
guitaramp on stage.Thishelpstremendously in eliminating buzz
and hum caused by ground loops. If, after you connect, you still
hear hum or buzz this can usually be eliminated by switching the
¼” ground lift switch to the upward position.
The piezo channel is equipped with two filters. The hi-cut (low
pass) filter is designed to roll off the high end from the piezo as
these can often sound harsh or edgy. There are three settings:
Start by setting it to bypass (flat) and listen. Then move the
switch to the first and second filter set to select the position you
find sounds best. The lo-cut (high-pass) filter employs the same
functionality only this time; it is used to roll off excessive bottom
endtoprevent resonant feedback.Thisis particularly useful when
sending the acoustic signal to a full range PA system.

TruetotheMusic
Radial Engineering Ltd. PZ-DI™User Guide
6
The Built In Direct Box
The PZ-DI is equipped with a built-in active Radial DI box that
works exclusively with the piezo channel. This DI circuit is similar
to the popular Radial J48 in that it is active and able to handle
plenty of level without distortion. There are two dedicated slider
switches for the direct box: a ground lift that lifts pin-1 at the XLR
output connector and a 180º polarity reverse. The 180º polarity
reverse switch is recessed as a reminder that it can sometimes
causepopping when switched.To avoid popping,always turn the
volume levels down before setting the polarity.
The 180º polarity reverse is used to ‘phase align’ the output go-
ing to the PA so that it better mixes with the monitors and stage
amp sounds. Resonant feedback is often caused by the stage
amplifiers and monitors interacting with the PA system creating
‘hot spots’ called "modes" on stage. Reversing the polarity will
change the phase relationship between the speakers and move
the hot spot to a different location on-stage. Using the 180º po-
larity switch in this way can help reduce resonant feedback from
your acoustic guitar.
The Tuner Out
Thisis a separatelybufferedoutput that feedsan electronic tuner
with both magnetic and piezo pickup signals at all times. Tuners
areknown to sometimescause a faintclicking noise producedby
their clocking circuitry. Because the PZ-DI’s tuner out is buffered,
clock noise from the tuner is blocked from leaching back into the
signal path.
Using The PZ-DI With Two Instruments
The PZ-DI will undoubtedly find many fans with those that switch
between electric and acoustic instruments on stage. Hook up is
nodifferentthandescribedabove… just usetwoinstruments with
two cables and you are set to go!

TruetotheMusic
Radial Engineering Ltd. PZ-DI™User Guide
7
CONNECTING AND USING EFFECTS PEDALS
Using Effect Pedals With The Acoustic Piezo Channel
Another cool feature built into the PZ-DI is the effects loop. This
is dedicated to the piezo acoustic channel as a means of adding
effectstotheacoustic signal path.Thisway, youracoustic pickup
can have effects like reverb or a more radical EQ routed to both
youron-stageamp and to the PAandmonitor systems.ThePZ-DI
uses an "insert" type TRS ¼” jack for the effects loop where the
send and return are are combined into one jack.
Effect pedals connected to the acoustic piezo effects loop are
routed to the acoustic amplifier output and the DI output.
Using Effect Pedals With The Electric Magnetic Channel
Forthe electric-magnetic pickupsignalpath, pedals wouldsimply
beconnectedfromthe ¼” electric outputbeforegoingto the stage
amp. The PZ-DI will act as a buffer for the pedals which will quiet
them down and allow longer cable runs to 50 feet (15 meters)
without appreciable noise.
The electric-magnetic channel features a high-quality buffered output
that can drive long cables and true-bypass pedals. To introduce effects
on the electric-magnetic channel pedals are placed after the PZ-DI .

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Radial Engineering Ltd. PZ-DI™User Guide
8
FAQ
Can I use the PZ-DI with two electric guitars?
You could, but you may be better served with the lower priced
BigShot i/o. The PZ-DI is not designed to send the two pickup
signals to the same amp. So this may not work for your setup.
Why does the PZ-DI use a 15V volt supply - not a 9V?
Unlike guitar pedals that merely need to control electric guitars,
the PZ-DI also must control acoustic signals. These tend to have
radical transients with more dynamic range. This means it needs
moreheadroom. More headroom isaccomplishedwith more volt-
age, thus the reason we use a 15 volt supply.
Will the PZ-DI alter my electric guitar tone?
Yes and no. The PZ-DI will buffer your guitar and it will lower the
impedance. This lowers noise, allows you to run longer cables
and eliminates the popping when you switch pickups on and off.
To counter any effect that the buffers may have on the signal, we
have added a feature called Drag Control. This lets you adjust
the load on the pickup so that it sounds natural. Carlos Santana,
JohnPetrucci,andSteveLukatheralluseRadialbufferswithDrag
Control when they record. We think they would be just about as
picky as anyone else!
Can I use the Tuner out as a combined output?
Yes, but there is no way to turn it off. This output is always active.
Can I power the PZ-DI using 48V phantom from a mixer?
No. Phantom power does not have enough current to power the
PZ-DI. This is why the PZ-DI comes with a power supply.
Will turning on the phantom power hurt the PZ-DI?
No.ThePZ-DIisequippedwithDCblockingcapacitorsattheXLR
output connector to protect it from phantom power.
Can I leave the PZ-DI powered on when I'm not using it?
Yes. The PZ-DI is designed to work continuously and leaving the
powerconnected will notcause any harmto the PZ-DI or devices
connected to it.
Why does the 180º polarity switch sometimes cause popping?
Thishas to dowith DC offsetsatthe ins andouts of otherdevices
the PZ-DI is connected to. Theoretically the inputs and outputs
of an audio device should be exactly at zero volts. But due to
imperfections within the electronic components like op-amps
and capacitors, sometimes there can be several millivolts of DC
present. This small amount of DC voltage creates a potential for
current to flow and can cause a popping sound when it does.
While the PZ-DI is designed correctly to avoid DC offsets we can
not be sure about other devices it is connected to. Turning down
the volume before switching the polarity is a safe way to avoid
loud transients from reaching the loudspeakers.

TruetotheMusic
Radial Engineering Ltd. PZ-DI™User Guide
9
Radial PZ-DI Specifications
Acoustic Piezo Input: ¼" Phone unbalanced,
10 Meg Ohm input impedance
LOW-CUTFilter: Low frequency cut-off at 75Hz and 220Hz
HI-CUT Filter: High frequency cut-off at 2.8kHz and 7.2kHz
Effects Loop (Acoustic
Piezo): ¼" TRS Phone unbalanced insert type Tip= effects send, Ring= effects return
Acoustic Output: ¼" Phone unbalanced,
10k ohm output impedance
Electric Pickup Input
Drag Control: ¼" Phone unbalanced, Variable 10k - 1 MegOhm input impedance
Electric Pickup Output: ¼" Phone unbalanced,
10k Ohm output impedance
Tuner output: ¼" Phone unbalanced,
10k ohm output impedance
XLR Output: XLR balanced 600 ohm mic-level,
pin-out (AES standard):
pin 1 ground
pin 2 hot (+)
pin 3 cold (-)
Power supply: 15VDC, 400mA(included), center pin positive
Size (W x D x H): 5.75"x 3.75”x1.99” (146 x 95 x 50mm)
Weight: 1.75 lbs. (0.8 kg)
Warranty: 3 Years, transferable
LOW-CUT
FILTER
HIGH-CUT
FILTER
BLOCK DIAGRAM

TruetotheMusic
1588 Kebet Way, Port Coquitlam BC V3C 5M5
tel: [phone] fax: [phone] email: [email protected]
www.radialeng.com
Tonebone PZ-DI Users Guide v1.0 - Feb. 2010 - Part #: R870 1237 00
Specifications and appearance subject to change without notice.
Copyright © 2010 Radial Engineering Ltd.
RADIAL ENGINEERING LTD.
3 YEAR TRANSFERABLE WARRANTY
Radial Engineering Ltd. warrants this product to be free from defects
inmaterialandworkmanshipandwillremedyanysuchdefectsfreeof
chargeaccordingtothe termsofthiswarranty.RadialEngineeringwill
repairorreplaceatitsoptionanydefectivecomponent(s)ofthisproduct,
excluding the finish, the tube, the footswitch (tubes and footswitches
are under warranty for 90 days) and wear and tear from normal use,
foraperiodofthree(3)yearsfromtheoriginaldateofpurchase.Inthe
eventthataparticularproductisnolongeravailable,RadialEngineering
reservestherighttoreplacetheproductwithasimilarproductofequal
orgreatervalue.Tomakearequestorclaimunderthislimitedwarranty,
theproductmustbereturnedprepaidintheoriginalshippingcontainer
(orequivalent)to Radial Engineering ortoan authorized repair centre
andyoumustassumetheriskoflossordamage.Acopyoftheoriginal
invoiceshowingdateofpurchaseandthedealernamemustaccompany
anyrequest for workto be performed under thislimited warranty.This
limited warranty shall not apply if the product has been damaged due
to abuse, misuse, misapplication, accident or as a result of service or
modification by any other than an authorized repair centre.
THEREARENOEXPRESSEDWARRANTIESOTHERTHANTHOSE
ON THE FACE HEREOFAND DESCRIBEDABOVE. NO WARRAN-
TIESWHETHEREXPRESSEDORIMPLIED,INCLUDINGBUTNOT
LIMITED TO,ANY IMPLIED WARRANTIES OF MERCHANTABILITY
OR FITNESS FOR A PARTICULAR PURPOSE SHALL EXTEND
BEYOND THE RESPECTIVE WARRANTY PERIOD DESCRIBED
ABOVE OF THREE YEARS.
RADIALENGINEERINGSHALLNOTBERESPONSIBLEORLIABLE
FORANYSPECIAL,INCIDENTALORCONSEQUENTIALDAMAGES
ORLOSSARISINGFROMTHEUSEOFTHISPRODUCT.THISWAR-
RANTYGIVESYOUSPECIFICLEGALRIGHTS,ANDYOUMAYALSO
HAVEOTHERRIGHTS,WHICHMAYVARYDEPENDINGONWHERE
YOU LIVEAND WHERETHE PRODUCT WAS PURCHASED.