Fishman PREFIX PRO BLEND User Manual

User Guide

®

User Guide

Prefix Pro Blend

Acoustic Guitar System

Warning! We strongly recommend that you familiarize yourself with the

preamp's controls before you attempt to perform with this system.
Failure to do so can produce painful acoustic feedback (see Quick Start
on page 3). Please take a few minutes to read this guide and familiarize
yourself with the Pro Blend's controls.

Prefix -

Stereo Blender

Stereo Blender

Prefix -

Thank you for choosing a Fishman equipped instrument. Our goal is to provide you
with the finest acoustic amplification products available-systems that simply let you
sound your best. With our long-standing commitment to quality, you can feel confi­dent that your Fishman gear will provide great sound and trouble free performance
for years to come.

Your satisfaction is very important to us. If you have any questions, please contact
us on the web at [e-mail]; or by telephone at 978-988-9665.

Featured for the Pro Blend is the acclaimed Acoustic Matrix under-saddle pickup. It
delivers a clear, articulate sound with emphasis on string definition and attack. To
compliment and contrast this pickup, a miniature electret microphone (mounted to
the underside of the preamp chassis) captures the guitar's elusive natural ambi­ence and sound chamber resonance. Blend the pickup and Microphone together for
a powerful and cohesive acoustic guitar tone that is deeper and more "filled out",
than the sound of either the microphone or pickup alone.

The Prefix Pro Blend preamp module incorporates a unique flip-top battery compart­ment for easy access. Levels are set by the master volume and blend controls.
Traditional shelving-style bass & treble, plus a semi-parametric "Contour" EQ are
included so you can shape your guitar's tone exactly to taste. To complete the
package, we include a phase switch and an adjustable notch filter, both essential for
fighting feedback.

THE PICKUP

The system's under-saddle pickup is the industry standard Fishman Acoustic
Matrix. It is made with Fishman's exclusive co-polymer sensing material. This pro­prietary material reproduces your acoustic guitar sound with a sensitivity and
dynamic range that surpasses all other known materials (including piezo-ceramic
and so called "piezo-film" pickups).

2

2

SER

SER

G

G

UIDE

UIDE

U

U

At the heart of the pickup is a multi-layer sandwich of co-polymer strips. These
strips sense motion across the entire length of the saddle for unparalleled perfor­mance. Compared ceramic pickups with individual elements, the Acoustic Matrix'
"unitary" co-polymer design provides a more natural and balanced response, with
sensitivity to both the strings and the soundboard. The transducer is fully enclosed
in a shielded foil wrap for dead quiet performance and total EMI noise rejection.

THE MICROPHONE

This quality electret-condenser microphone will provide very high level sound repro­duction before feedback when used in conjunction with the unit's Phase, Notch and
Contour EQ (see page x). Conveniently shock-mounted to the underside of the pre­amp chassis, the microphone is strategically isolated inside the instrument. For
stage use, the Microphone's interior location affords you unprecedented freedom of
movement as well as minimal bleed through from other instruments.

QUICK START

We recommend that you preset the system EQ to locate and eliminate microphone

feedback before you mix in the under-saddle pickup.

1. Set all controls as follows:

2. Slowly increase the volume and play the notes from the open low E, up to the

•

Notch and Volume fully counter-clockwise

•

All EQ sliders at center position

•

Blend slider at lowest position (B = microphone)

fourth fret G sharp until the instrument starts to rumble or howl with feedback on
one or more of these notes. Adjust the Notch control until this feedback is elimi­nated (usually between one and two o'clock on the dial).

3

3

Prefix -

Prefix -

3. Increase the volume some more and play (on the low E string) the fifth fret A
and above. Flip the phase switch to the position that eliminates feedback in this
region.

4. Slowly increase the Volume again, until you start to hear a high squeal.

5. Lower the Contour slider all the way down and adjust the Frequency slider until

the squealy feedback is eliminated. Raise the Contour slider (if possible) to just
below the threshold of feedback.

6. Move the Blend slider up to mix in the pickup signal (A).

7. Adjust the Bass and Treble controls as desired. Note that these controls do not

affect the microphone signal.

8. Play your guitar as loud as you like.

Stereo Blender

Stereo Blender

See diagram on page 9

SETUP

Battery Compartment

Pull the small tab at the top of
the Onboard Blender™ toward
you. The body of the preamp
will swing out, revealing the
battery compartment. Observe
the polarity marks on the bat­tery clip and install a fresh 9V
alkaline battery accordingly.

4

4

SER

SER

G

G

UIDE

UIDE

U

U

Microphone Trim Control

A small circular potentiometer is located on the side of the preamp that faces the
back of the guitar. This control can be accessed by opening the battery compart­ment. Set the Blend slider to the center position and with a small slotted screwdriv­er and adjust the Trim Control until both the microphone and pickup levels are bal­anced to your taste.

Endpin Jack

When you plug into the endpin jack, the Prefix Pro Blend switches on. To conserve
the battery, remove the instrument cable from the endpin jack when the system is
not being used. It is a good idea to turn down your amp or mixer input before you
plug into the endpin jack. Doing so will protect your speakers (and your ears) from
loud pops.

Battery Low LED

Plug into the endpin jack and the Low Battery light will flash momentarily, indicating
that the power is on. When the Low Battery light stays on, it is time to change the
battery.

5

5

Prefix -

Prefix -

Stereo Blender

Stereo Blender

CONTROLS

Volume Control

This is a master volume control for both the pickup and the microphone. Set this as
high as possible (without distorting your amp or mixer) for the cleanest signal.

Notch and Phase

These controls work hand in hand to suppress two adjacent ranges of acoustic
feedback. When you set them properly, you can play your instrument as loud as
you like, feedback free.

Notch

Tune the Notch filter to scoop out the lowest range of feedback when you play
bass notes between the open low E string and (up to and including) the forth fret
G sharp on the same string. Low frequency "cavity resonance" feedback can
usually be squelched by setting the Notch control between one o'clock and two
o'clock on the dial. Note that for instruments that do not suffer from low fre­quency feedback, the notch can be defeated by moving the dial to the Off
(seven o'clock) position.

Phase Switch

Flip the Phase switch back and forth until you find the position that sounds best
and subdues mid-bass feedback. Mid-bass feedback generally occurs when you
play bass notes above the fourth fret G sharp on the low E string.

Bass

This control affects the under-saddle pickup signal only! A Boost here will add
depth and weight to the sound the instrument.

6

6

Lower Feedback Range

(E to G#)

Upper Feedback Range

(A and above)

U

U

SER

SER

G

G

UIDE

UIDE

7

7

Prefix -

Prefix -

Stereo Blender

Stereo Blender

Contour EQ

The Contour slider and the Frequency knob make up this EQ. The Frequency knob
lets you tune in on the specific range of sounds that you can boost/cut with the
Contour (level) slider.

With the Contour EQ you can boost or cut a wide range of frequencies, from gutsy
low midrange (250 Hz) to brilliant high treble (10 kHz). Often your instrument will
benefit from a slight midrange cut.

To cut mids, boost the Contour control and then sweep the Frequency control until
you find the band of frequencies that are brash and nasal sounding (usually around
the middle center of the Frequency knob's travel). Then move the Contour slider
below its detent to taste.

Treble

This control affects the under-saddle pickup signal only! A boost here will help
to "cut through the mix". Conversely, cutting the Treble will mellow and subdue your
amplified tone.

Blend Control

This control determines the balance between the two pickups. Move the slider left to
emphasize the Microphone (B). Move it right to hear more of the Pickup (A).

8

8

SUGGESTED EQ SETTINGS

Anti-feedback

See Quick Start on Page 3

SER

SER

G

G

UIDE

UIDE

U

U

Brilliance

If you are playing through a limited range
amplifier (like an electric guitar amp) or
have dead strings on the instrument, you
can brighten up your sound by setting the
Frequency knob all the way to the right
and raising the Contour (level) slider to
taste. If you plan to play at high stage
volume levels, dial in more pickup than
microphone to avoid feedback.

9

9

Prefix -

Prefix -

Suggested EQ Settings Cont’d ...

Stereo Blender

Stereo Blender

Mid-Cut

You can scoop out harsh midrange by
setting the Frequency knob at about
12:00 and the Contour (level) slider
cut to taste below the center detent.
Often the desired mid-cut will fall into
the same frequency range as poten­tial microphone feedback. You can
also cut midrange (pickup only) by
boosting the BASS and TREBLE slid­ers to realize an "implied" mid-cut at
800 Hz.

Fingerstyle

This setting will add fullness to the bass
and definition to the treble.

10

10

SER

U

G

U

SER

G

SPECIFICATIONS

Nominal Input Level: -20 dBV
Input Overload: (20 Hz - 20 kHz)-2 dBV
Pickup Input Impedance: 20 M Ohms
Output Impedance: Less than 3.5 k Ohms
Nominal Output Level: -12 dBV
THD: Less than .04 %, -20 dBV input
Signal to Noise Ratio: 77 dB

Current Drain: Less than 4 mA
Power Supply: 9V alkaline battery

Notch Filter Range: 20Hz - 300 Hz (-15 dB)
Bass Control Range: ± 12 dB at 60 Hz

Treble Control Range: ± 12 dB at 10 kHz

Contour Control Range: ± 12dB

All specifications subject to change without notice.

(A weighted referred to nominal

-20 dBV input)

(estimated 140 hours continuous use
with low battery indicator at 6.5V)

± 3 dB at 350 Hz

± 3 dB at 2.4 kHz

(adjustable from 250 Hz to 10 kHz)
Q = 0.5

UIDE

UIDE

11

11

Limited Warranty

®

Limited Warranty

The Fishman Prefix Pro Blend is warranted to function for a period of One (1) Year
from the date of purchase. If the unit fails to function properly within the warranty
period, free repair and the option of replacement or refund in the event that
Fishman is unable to make repair are Fishman’s only obligations. This warranty
does not cover any consequential damages or damage to the unit due to misuse,
accident, or neglect. Fishman retains the right to make such determination on the
basis of factory inspection. Products returned to Fishman for repair or replacement
must be shipped in accordance with the Return Policy, as follows. This warranty
remains valid only if repairs are performed by Fishman. This warranty gives you
specific legal rights and you may also have other rights which may vary from state
to state.

Return Policy

To return products to Fishman Transducers, you must follow these steps...

1. Call Fishman Transducers at 978-988-9665 for a Return Authorization Number
(“RAN”).

2. Enclose a copy of the original Bill of Sale as evidence of the date of purchase,
with the product in its original packaging and a protective carton or mailer.

3. Fishman Transducers’ technicians will determine whether the item is covered by
warranty or if it instead has been damaged by improper customer installation or
other causes not related to defects in material or workmanship.

4. Warranty repairs or replacements will be sent automatically free of charge.

5. If Fishman Transducers determines the item is not covered by warranty, we will

notify you of the repair or replacement cost and wait for your authorization to
proceed.

340-D Fordham Road Wilmington MA 01887 USA

F

ISHMAN

Phone [phone] • Fax [phone]

T

RANSDUCERS

www.fishman.com

009-089-005 1-01