The Ancient Order of the Mystic Magnetic Pickup

Innovation. Amplified.
Chapter 5
The Ancient
Order of the
Mystic
Magnetic
Pickup
by
Hartley Peavey
T
he Ancient Order of the Mystic Magnetic Pickup
The Beginning
Interestingly, here in the new millennium there is
The invention of the telegraph (in the mid 1800’s)
still more mystery, BS, and misunderstanding regardenabled long distance communication for the first
ing guitar and bass pickups than almost any other astime. These early telegraphs had no means to make a
The
Ancient
Order
of the Mystic
Magnetic
Pickupsound, except through the use of an electromagnetic
pect
of musical
instruments.
Because
pickups seem
“mysterious,” many players tend to attribute “super“clicker,” that attracted a small metal bar when a current
erestingly,natural
here inabilities”
the new
still more
mystery,
BS,flowed
and through the telegraph wire into the
to millennium
what really isthere
a fairlyissimple
device
(signal)
standing regarding
guitar
bassconfigurations
pickups thanand
almost
of these telegraph “receivers” were
(that can be
madeand
in many
fromany
a other
clickeraspect
coil. Since
nstruments.number
Because
pickups
seem
“mysterious,”
many
players
tend
to
of different materials). The basic principles reBeginning
incapable of making any sound, other than The
a “click”,
a
“supernatural
abilities”
to what
a fairly
simple device (that
can be
made
main
exactly the
same really
as the is
very
first pickups.
primitive
“digital
format” was invented by Samuel
configurations and from a number of different materials). The Morse.
basic principles
Obviously,
I’m referring
what most
The invention
of the to
telegraph
(inpeople
the mid 180
xactly the same
as
the
very
first
pickups.
The so-called “electric guitar” has been around far lonknow
as
“Morse
code”
(consisting
of
long
and
short telegra
communication for the first time. These early
ger than most guitar players are aware. Even very few
periods
of
current
flow
often
called
“dots
and
dashes”).
sound, except through the use of an electromagnetic
he so-calledmusic
“electric
guitar”
has been
around
than most
guitar
industry
veterans
are aware,
that far
the longer
first known
In
order
for this
longadistance
to through
work,
metal
bar
when
currentcommunication
(signal) flowed
the
re aware. patent
Even very
music guitar”
industry
veterans
aware, that
the
first
for anfew
“electrified
was
issued toare
George
both
the
sender
and
the
receiver
had
to
know
the
Since these telegraph “receivers” were incapable
of
atent for anBreed
“electrified
issued
Breed
the United
(of theguitar”
United was
States
Navy)toonGeorge
September
2, (of“Morse
code,” and to be able to send and receive the
“click”, a primitive “digital format” was invented by Sa
avy) on September
2, 1890
(US Patent
number
of this code
patent
1890 (US Patent
number
435,679)!
A copy435,679)!
of this pat- A copy
appropriate
for numerals and the letters of the
referring to what most people know as “Morse code”
The Beginning
is attached for your perusal.
ed for your ent
perusal.
alphabet.
periods of current flow often called “dots and dashes
communication
to technology
work,
the sender
and the rece
The invention of the telegraph (in theAs
mid
1800’s)
longboth
distance
soon
as thisenabled
basic
became
widespread
and
to
be
able
to
send
and
receive
the
appropriate
c
communication for the first time. These early
telegraphs
had no that
means
make a electrical
(and
people realized
longtodistance
the alphabet.
communication
was that
possible)
a worldwide
sound, except through the use of an electromagnetic
“clicker,”
attracted
a small search
beganthe
for ways
to electrically
transmit
human
voice
metal bar when a current (signal) flowed through
telegraph
wire into
the the
clicker
coil.
As
soon
as
this
basic
technology
became
wid
over
wires.
Instead
of
relying
on
the
“Morse
code”
Since these telegraph “receivers” were incapable of making any sound, other than a
long
distance
electrical
communication
was
possible
(wherein
the message
hadObviously,
to be codedI’m
by the sender
“click”, a primitive “digital format” was invented
by Samuel
Morse.
and
then
decoded
by
the
operator
at
the receiving
ways
to
electrically
transmit
the
human
voice over wi
referring to what most people know as “Morse code” (consisting of long and short
end)
they
wanted
to
transmit
VOICE
down
the
code”
hadwires.
to be coded
periods of current flow often called “dots and“Morse
dashes”).
In (wherein
order for the
thismessage
long distance
There
isoperator
some debate
about
who actually
invented
by
the
at
the
receiving
end)
they
wanted to
communication to work, both the sender and the receiver had to know the “Morse code,”
what
we
now
call
the
telephone,
but
most
agree
that
it
There iscode
some
about
and to be able to send and receive the appropriate
fordebate
numerals
andwho
theactually
letters ofinvented w
was
Alexander
Graham
Bell
(who
patented
the
first
most agree that it was Alexander Graham Bell (who
the alphabet.
practical
telephone).
He invented
the telephone
in and w
telephone).
He invented
the telephone
in 1874
1874 and was granted a patent on his invention in
invention in 1876.(and
In order to realized
do this, he had to inven
As soon as this basic technology became
1876. widespread
In order to do this, people
he had to invent athat
way to
current and
to change search
this varying
signal
into a soun
long distance electrical communication was modulate
possible)
a
worldwide
began
for
an electrical current and to change this
ways to electrically transmit the human voicevarying
over signal
wires.intoInstead
on the
a soundof
at relying
the receiving
end.
“Morse code” (wherein the message had to be coded by the sender and then decoded
by the operator at the receiving end) they wanted to transmit VOICE down the wires.
There is some debate about who actually invented what we now call the telephone, but
most agree that it was Alexander Graham Bell (who patented the first practical
telephone). He invented the telephone in 1874 and was granted a patent on his
invention in 1876. In order to do this, he had to invent a way to modulate an electrical
current and to change this varying signal into a sound at the receiving end.
Telephone Carbon Mic
Telephone Carbon Mic
Bell discovered that if he used a flexible diaph
of carbon particles, the pressure on the diaphragm w
As you might imagine, over the many decades since
s you might imagine, over the many decades since then, pickupgranules;
technology
hascausing the current through the conn
thus,
then, pickup technology has gone in many directions
many directions using both magnetic and so-called “Piezo,” pronounced
pi-Á-zo
movement
of the diaphragm. Essentially, Bell discov
using both magnetic and so-called “Piezo,”
zo!). This type
of
pickup
uses
a
crystal
or
ceramic
element
that
produces
resistor” controlled by the movement of a thin diaphr
pronounced pi-Á-zo (not pie-zo!). This type of pickup
y when the uses
element
is “stressed”
or bent
in some
a crystal
or ceramic
element
that way.
produces
amplification devices during that time, Bell discovere
Telephone
Carbon
Telephone
“Receiver”
electricity when
the element
isMic
“stressed” or bent in
Telephone
“Receiver”
of electricity at
the
audio
rate by utilizing a diaphragm
some way.
electrically conducting carbon granules. This was th
2 led to the telephone. It was understood by the 1880s
Bell discovered that if he used a flexible
diaphragm pressing
against a “capsule”
2
coil could
move
a piece
of magnetic
material in direc
of carbon particles, the pressure on the diaphragm
would
variably
compress
the carbon
patent on this on January 20th 1874. The rest is history, and innovation is continuing to
the present.
Bell discovered that if he used a flexible diaphragm
pressing against a “capsule” of carbon particles, the
pressure on the diaphragm would variably compress
the carbon granules; thus, causing the current through
the connecting wires to vary with the movement of the
diaphragm. Essentially, Bell discovered a way of
making a “variable resistor” controlled by the movement
of a thin diaphragm. Since there were no known
amplification devices during that time, Bell discovered
a novel way of controlling the flow of electricity at the
audio rate by utilizing a diaphragm to vary pressure on
the electrically conducting
carbon
granules.
Thisjust
wasa variation of the telegraph “receiver”, except that the
The first
speakers
were
the first practical
microphone,
which
led
to
the
moving part of this device was connected
to a diaphragm capable of moving air. Once
telephone. It Mr.
was Bell
understood
by the his
1880s,
that a
demonstrated
“telephone”,
inventors realized that sound could be
varying current
flow in a coil
could move
a piece
of
reproduced
through
electrical
means.
At about the same time, Ernst Siemens
magnetic material
in
direct
proportion
to
the
amount
of
(Germany) thought up the idea of a “dynamic” (moving) coil transducer. He filed a US
current flowingpatent
through
coil.
onthe
this
on January 20th 1874. The rest is history, and innovation is continuing to
the present.
The first speakers were just a variation of the telegraph
Most instruments, up until the first part of the 20th Century, were so-called
“receiver”, except that the moving part of this device
“acoustic” instruments (brass and woodwind “horns”, and a wide variety of string or
was connected to a diaphragm capable of moving air.
percussion instruments that depended on natural resonance or “horn loading” to
Once Mr. Bell demonstrated his “telephone”, inventors
achieve
their
The reason for the above discussion on the first microphones is
speakers
were
just aoutput).
variation
realized The
that first
sound
could be
reproduced
throughof the telegraph “receiver”, except that the
because,
the first “guitar
pickups” WERE
various
formsair.
of MICROPHONES
attached t
moving part
of this
wassame
connected
to a diaphragm
capable
of moving
Once
electrical
means.
At device
about the
time, Ernst
conventional
acoustic
instruments
(such
as
pianos
or
guitars).
Breed’s
patent
utilized
Mr. Bell(Germany)
demonstrated
his
inventors realized that sound could be
Siemens
thought
up“telephone”,
the idea of a “dynamic”
battery
coilAtto
energize
the strings
which were attached to a
reproduced
through electrical
means.
about
time, themselves
Ernst Siemens
(moving)
coil transducer.
He
filed aand
US apatent
on
this the same
traditional
acoustic
resonator
(since,
at
that
time,
there
wasano
(Germany)
thought
uprest
theisidea
of and
a “dynamic”
USsuch thing as vacuum
on
January 20th
1874. The
history,
innovation(moving) coil transducer. He filed
th amplify the sound generated by the string). The Siemens’ loudspeaker was,
tubes
to
on this
onpresent.
January 20 1874. The rest is history, and innovation is continuing to
ispatent
continuing
to the
the present.
likewise, THEN impractical except through the use of a “carbon microphone.”
A Hot Idea
As most people know, Thomas Edison was the first to invent a practical
incandescent light bulb. The so-called “Edison bulb” had a Tungsten filament, and the
glass bulb itself contained a Most
vacuum
that enabled
thethe
Tungsten
“white hot”
instruments,
up until
first parttoofglow
the 20th
(without destroying itself through
instant
oxidation).
Century, were so-called “acoustic” instruments (brass
and woodwind “horns”, and a wide variety of string or
percussion
instruments
that were
depended
on natural
Most instruments, up until the first
part of the
20th Century,
so-called
resonance
or
“horn
loading”
to
achieve
their
“acoustic” instruments (brass and woodwind “horns”, and a wide variety of stringoutput).
or
reason resonance
for the above
discussion
on tothe first
percussion instruments that depended The
on natural
or “horn
loading”
microphones
is because,
the first
first microphones
“guitar pickups”
achieve their output). The reason for the
above discussion
on the
is
WERE various forms of MICROPHONES attached to
because, the first “guitar pickups” WERE various forms of MICROPHONES attached to
conventional acoustic instruments (such as pianos or
conventional acoustic instruments (such
as pianos or guitars). Breed’s patent utilized a
guitars). Breed’s patent utilized a battery and a coil to
battery and a coil to energize the strings themselves which were attached to a
energize the strings themselves which were attached
traditional acoustic resonator (since, at that time, there was no such thing as vacuum
to a traditional acoustic resonator (since, at that time,
tubes to amplify the sound generated by the string). The Siemens’ loudspeaker was,
there was no such thing as vacuum tubes to amplify
likewise, THEN impractical except through
the use of a “carbon microphone.”
the sound generated by the string). The Siemens’
Most instruments, up until the first part of the
20th Century,
so-called
loudspeaker
was,were
likewise,
THEN impractical except
“acoustic” instruments (brass and woodwind “horns”,
and
a
wide
variety
of
string
or
through the use of a “carbon microphone.”
A Hot Ideaor “horn loading” to
percussion instruments that depended on natural resonance
achieve their output). The reason for the above discussion on the first microphones is
As most
people WERE
know, Thomas
Edisonofwas
the first to invent
a practical
because, the first “guitar
pickups”
various3 forms
MICROPHONES
attached
to
incandescent
light
bulb.
The
so-called
“Edison
bulb”
had
a
Tungsten
filament,
conventional acoustic instruments (such as pianos or guitars). Breed’s patent utilized
a and the
A Hot Idea
As most people know, Thomas Edison was the first to
invent a practical incandescent light bulb. The socalled “Edison bulb” had a Tungsten filament, and the
glass bulb itself contained a vacuum that enabled the
Tungsten to glow “white hot” (without destroying itself
through instant oxidation)
hot filament and the anode (plate) connected to a high
voltage. These gentlemen created a kind of “electric
valve” which enabled control of the flow of electrons
through the vacuum, just as the earlier carbon
microphone controlled the flow of electrons by varying
the pressure exerted on carbon granules, thus,
changing its resistance in direct proportion to the
pressure applied.
dison’s bulbs
ushered
inushered
electricinlighting
and seemed
to work reasonably well
Edison’s
bulbs
electric lighting
and seemed
to work
well for
extended
periods,
withbulbs”
the tended to turn
ded periods,
with reasonably
the exception
that
these early
“light
exception
“light bulbs”
tendedtried
to turn
side the glass
bulb) that
overthese
time.early
Edison’s
laboratory
many approaches to
blackproblem
(inside through
the glassthebulb)
time. techniques;
Edison’s
s “blackening”
use over
of various
one of which was
Although there is some controversy about who actually
laboratory
tried many
approaches
to solve
this
a small metal
rod through
the glass.
The Edison
lab discovered
that when
this tube triode, most people on this
invented
thecontroversy
vacuum
Although
there
is
some
who actually invented the
“blackening”
problem
through
the
use
of
various
ing rod”bulbs
was attached
to electric
a POSITIVE
voltage,
electrons
wouldreasonably
flowofthrough
thecredit about
side
the
Atlantic
DeForest
that invention.
dison’s
ushered in
lighting
and
seemed
to
work
well
triode,
most
people on was
this side
of “the
the Atlantic creditfor
DeForest
for that inven
one of which
was inserting
a small
metal
of
theperiods,
bulbtechniques;
into
thethe
rod…Not
surprisingly,
this
new
phenomenon
called
Regardless
of
who
actually
invented
it
first,
the vacuum
ded
with
exception
that theseRegardless
early
“light
bulbs”
tended
to
turn
of
who
actually
invented
it
first,
the
vacuum
valve
made
possib
rod they
through
the
glass. The
lab discovered
that rectifier tube).
Effect”…What
had
created
wasEdison
a “vacuum
diode”
(AKA
valve
made
possible
electronic
amplification
and
thus,
side the glass
bulb)
over
time.
Edison’s
laboratory
tried
many
approaches
to
amplification
and thus, opened the way for AM radio, amplified instruments
when this “conducting rod” was attached
to a POSITIVE
opened
waywas
forpictures.”
AM radio, In
amplified
instruments,
s “blackening”
problem
through
the
use
of
various
techniques;
one of the
which
reinforcement,
and so-called
“talking
1911, Ed
Prindham and
voltage, electrons would flow through the vacuum of
sound
reinforcement,
and
so-called
“talking
pictures.”
a small metal
rod
through
the
glass.
The
Edison
lab
discovered
that
when
this
inventedthis
the new
first practical (and manufacturable) moving coil loudspeaker c
the bulb into the rod…Not surprisingly,
1911,
Ed Prindham
ing rod” was
attached towas
a POSITIVE
electrons wouldInflow
through
the and Peter Jensen invented the
“Magnavox”.
phenomenon
called “the voltage,
Edison
Effect”…What
firstwas
practical
of the bulbthey
intohad
the created
rod…Not
this new
called (and
“the manufacturable) moving coil
wassurprisingly,
a “vacuum diode”
(AKAphenomenon
rectifier
loudspeaker
called
the “Magnavox”.
Effect”…What
they had created was a “vacuum diode”
(AKA
rectifieroftube).
With the
invention
“amplification” and the availability of various typ
tube).
microphones, inventors
little of
time
in using these
microphones
With wasted
the invention
“amplification”
and the
availability and s
reproducing devicesoftovarious
amplifytypes
both of
voice
and music.
The advent
of sound
microphones,
inventors
wasted
pictures was the single
greatest
factor
in
accelerating
the
development
of s
little time in using these microphones and sound
systems. Obviously,reproducing
microphones
hadtotoamplify
be developed
order
to create m
devices
both voiceinand
music.
soundtracks and these
were
quickly
utilized
to
amplify
traditional
“acoustic
The advent of sound in motion pictures was the single
A minor variation of greatest
the microphone
what
called a “contact
m
factor in produced
accelerating
thewas
development
of
These devices weresound
attached
solidlyObviously,
to a guitar
or piano soundboard
systems.
microphones
had to be and th
developed
order to create
into amplification and
speaker insystems.
Thesemovie
typessoundtracks
of pickups and
were som
these
wereto
quickly
utilized to the
amplify
traditionalof the in
nce the “Edison Effect” was described in the
literature,
inventors
all had
over
the
because
the string
sound
be transferred
soundboard
“acoustic
instruments.”
A minor variation
of the
gan experimenting. Fleming in the UK and
DeForest
discovered
then
picked in
upthe
by USA
the
so-called
“contact microphones,”
then amplified.
microphone
produced
what
was
called
a
“contact
he same time) that the electron flow could be “modulated” by placing a third
devices
were attached
solidly to with so
e between the hot filament and the anode (plate) Rickenbacker
connected tomicrophone.”
awas
high
voltage.
one
of These
the first
manufacturers
to dispense
a
guitar
or
piano
soundboard
and
then
plugged
entlemen created a kind of “electric valve”“contact
which enabled
control and
of the
flow the
of vibrations DIRECTLY frominto
microphones”
sense
the string
Once
the
“Edison
Effect”
was
described
in
the
literature,
amplification
and
speaker
systems.
These
types
of
snce
through
the
vacuum,
just
as
the
earlier
carbon
microphone
controlled
the
flow
themselves.
Many
(wrongly)
believe
the
so-called
“frying
pan”
lap
steel to
the “Edison
Effect”
was the
described
in the literature,
inventors
all
over
the
inventors
all
over
world
began
experimenting.
pickups
were
somewhat
limited,
because
the
string
ons
varying the pressure
exerted
on and
carbon
granules,
thus,
changing
its the very first electric guitar (though som
“electric”
guitar.
As
we
now know,
ganby
experimenting.
Fleming
inDeForest
the UK
DeForest
in the
USA
discovered
Fleming
in the
UK
and
in the
USA discovered
sound
hadMr.
to be
transferred
soundboard
of the Rick
ce
in
direct
proportion
to
the
pressure
applied.
impractical)
was
invented
by
Breed
some to
40the
years
earlier (1890).
he same time)
thatthe
the
electron
flowthe
could
be “modulated”
a third
(about
same
time) that
electron
flow could beby placing
instrument,
then
picked
up
by
the
so-called
“contact
guitar
was
certainlytoone
of the
earliest commercial electric guitars utilizing a
e between “modulated”
the hot filament
and the
anode
(plate)
connected
a high
voltage.
by placing
a third
electrode
between
the
microphones,”
then amplified.
pickup,
the
BASIC
principle
of
which
entlemen created a kind of “electric valve” which enabled control
of the flow of is much the same as the pickups on to
4
guitars.microphone controlled the flow
s through the vacuum, just as the earlier carbon
Rickenbacker was one of the first manufacturers to
dispense with so-called “contact microphones” and
sense the vibrations DIRECTLY from the strings
themselves. Many (wrongly) believe the so-called
“frying pan” lap steel to be the first “electric” guitar. As
we now know, the very first electric guitar (though
The process is started by pulling a trigger, which
somewhat impractical) was invented by Mr. Breed
“stresses” a Piezo element, thus, causing rapid
The process is started by pulling a trigger, which “stresses” a Piezo element,
some 40 years earlier (1890). Rickenbacker’s guitar
generation of electricity, which is fed to a small “spark
thus, causing rapid generation of electricity, which is fed to a small “spark gap” in the
was certainly one of the earliest commercial
electric
in Some
the nozzle
of the
gasuse
outlet.
Some“Piezo
cigarette
nozzle of the gasgap”
outlet.
cigarette
lighters
the same
effect” (ditto
guitars utilizing a magnetic pickup, the BASIC
principle
lighters
thegas
same
“Piezo effect” (ditto some ignition
some
ignition systems
inuse
small
engines).
of which is much the same as the pickups on today’s
systems in small gas engines).
In addition to the Piezo effect briefly described above, electricity can be
guitars.
generated by solar energy or chemically in a battery or in a fuel cell. This type of
In addition to the Piezo effect briefly described above,
electrical “generator” is only capable of producing so-called “direct current” and is not
electricity
can bedevice
generated
solar
really useful for any
kind of sensing
(pickup)by
which
is theenergy
topic of or
the present
chemically
in a battery
orgenerators
in a fuel utilized
cell. This
type o extremely
discussion. There
are also various
forms of
to produce
high voltages, which
are also
totally outside
thecapable
realm and
of thissopaper.
electrical
“generator”
is only
of scope
producing
called “direct current” and is not really useful for any
Almost allkind
the electrical
energy
created
in ourwhich
societyisutilizes
some
of sensing
device
(pickup)
the topic
ofvariation of
“magnetic generation”. Invariably, this involves magnetic fields. It has been known for
thethat
present
discussion.
There
arean
also
various
forms (wire)
hundreds of years,
electricity
is generated
when
electrical
conductor
generators
utilized
to produce
high(in relation to
moves through aofmagnetic
field. It
really doesn’t
matter ifextremely
the wire moves
voltages,
also totally
the“operative”
realm andword here is
the magnet) or the
magnetwhich
movesare
in relation
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Before
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generated
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which are“battery-less”
also totally outside the
realm and scope
of this devices
paper.
ng into any meaningful discussion of guitar and bass pickups, one high voltages,
producing
a guitar
pickup
incorporate a form of electrical generator that creates
hat there thus,
are several
ways tosound…Conversely,
generate an electrical signal
by sensing
all the electrical energy created in our society utilizes some variation of
bject (be itsenses
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of thediaphragm,
strings and
converts that
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As far
asalso
our discussion
here, we’re hundreds of years, that electricity is generated when an electrical conductor (wire)
energy,
it is
a “transducer.”
Essentially, there are two types of these; one type is
d in the kinds of transducers used on guitars and basses. Please moves through a magnetic field. It really doesn’t matter if the wire moves (in relation to
powered
by moves
a rotary
generator
activated
by aword
gear
ed “transducer” is ANY device that CONVERTS one form of energy the magnet)
or the magnet
in relation
to the wire.
The “operative”
here is
Almost
all
electricity
is
generated
by
a
“magnetic
MOTION,
which
is,
of
course,
is
an
indicator
of
ENERGY
being
expended.
mechanism,
which
translates
a
squeezing
motion
udspeaker IS a “transducer,” because it converts electrical energy into
process.”
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there
are
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produce
ne/diaphragm,
thus, producing
sound…Conversely,
guitartopickup
Piezo Mic
Pickup
into
rotary
motion,
thus,“battery-less”
generating
the electricity.
Most
of us
are aware
of the so-called
flashlight.
These devices
he stringselectricity,
and converts
thatas
into
electrical
energy, thus,
it is also
a
such
the
aforementioned
Piezo
elements
incorporate
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generator that
creates
electricity
by converting
MOTION
Another
type
today,
is the
so called
into
ELECTRICITY. Essentially, there are two types of these; one type is powered by a
that
generate
electricity
when
the isPiezo
element
isfire
An
example
of this type
of electricity
generation
those “snap
action”
“forever flashlight” pictured below.
starters or
candle lighters
that ignite
a small
gasorjettwisted).
used to light candles orrotary
fires. generator activated by a gear mechanism, which translates a squeezing motion
stressed
(such
being
bent
lectricity is
generated
by a as
“magnetic
process.”
Admittedly, there areinto rotary motion, thus, generating the electricity. Another more common type today, is
the so called “forever flashlight” pictured below.
uce electricity, such as the aforementioned Piezo elements that
y when the Piezo element is stressed (suchAn
asexample
being bentoforthis
twisted).
type of
electricity generation is
those “snap action” fire
starters or candle lighters
that ignite a small gas jet
used to light candles or
fires
7
Piezo Mic Pickup
e of this type of electricity generation is those “snap action” fire
5
8
This unit consists of a coil of wire, a very strong
magnet that is free to “slide” inside the coil, and a
small energy storage device called a CAPACITOR.
This unit generates electricity when the operator
rapidly “shakes” the unit so that the moving magnet
slides through the internal coil of wire. Because the
magnet slides through a coil of wire with multiple
turns, the magnetic field changes at the same rate as
the motion (energy) of the magnet. As the lines of
magnetic force “cut” thorough the coil, electricity is
generated. Simply put, this type flashlight translates
motion into electrical energy by moving a magnetic
field through the coil. It would work just as well if the
coil moved and the magnet was stationary, but this
would cause problems in terminating the coil’s output
leads.
attraction/repulsion is the basic principle of operation
of electric motors, loudspeakers, and many other
magnetic devices that we use and encounter in
modern life.
By definition, a magnet has two opposite poles.
Extending from all magnets is a magnetic “force,”
also known as a “magnetic field.” Generally, this field
radiates from the magnet’s North pole and its South
pole as illustrated above. This magnetic “field” is also
called “flux” or magnetic “lines of force.” The field
extends from one pole to the other as illustrated
above.
We’ve already mentioned that an electrical signal
(voltage) is generated when a conductor is moved in
relation to a magnet, or when a magnet is moved in
relation to a conductor (wire). This is also true if both
the conductor and the magnet are STATIONARY
when something “disturbs” (changes) the magnetic
field (which is the equivalent of motion). In the case of
a magnetic guitar pickup, the steel guitar strings are
capable of “disturbing” (changing) the magnetic field
of the stationary magnet. In magnetic guitar pickups,
the steel strings are placed in close proximity to the
magnetic poles and the adjacent coils of wire “sense”
the disturbance of the magnetic field caused by the
vibrating steel strings.
Permanent magnets have been known to science for
many centuries. The first magnets were called
“lodestones.” These were naturally occurring pieces
of iron that had become magnetized in their
environment. These types of materials were the
primary working elements of early compasses. Most
of us know that the Earth itself has an easily detectable
magnetic field, and that utilizing a permanent magnet
mounted to some kind of “pivoting arm” constitutes a
compass (because the magnetized indicator will
always “point” in the direction of the Earth’s North
and South poles). Magnets must have “polarity” in
order to be magnets. Traditionally, the “poles” of a
magnet have been called either North (N) or South
(S). Magnetic “poles” (as with many things in nature)
are attracted to the “opposite polarity.” In other words,
a magnet’s North pole will be “ATTRACTED” to
another magnet’s South pole while, the second
magnet’s North pole is REPELLED from the first
magnet’s North pole. Simply put: “OPPOSITE”
polarities ATTRACT, like polarities REPELL. This
Since the string is activated in some manner (by
being plucked, struck with some kind of hammer, or
“bowed”) the vibration of the string disturbs the
6
for strings; however, these tend to be utilized on
guitars with “non-magnetic” pickups, such as the
Piezo sensors described above or some kind of
“contact microphone” that senses changes in pressure
either under the “bridge” or the soundboard of the
instrument.
magnetic field at whatever frequency the string is
tuned to. It’s important to note, that the energy
imparted to the string causes the string to move in a
somewhat predictable manner and the motion of the
steel string causes the magnetic field to vary which, in
turn, induces a signal into the adjacent coil of wire at
the SAME RATE that the STRING is VIBRATING.
As referenced below, the “frying pan” guitar was
among the earliest commercial “electric guitars” to go
in production. Its pickup system utilized relatively
inefficient Tungsten/steel magnets of the period. Two
“U-shaped” magnets enclosed the pickup coil with
iron polepeices AND the STRINGS! In this early
design, the strings AND the coil were “inside” the
magnets; a relatively inefficient and ergonomically
poor approach, since the so-called “horseshoe”
magnets were on top of, as well as, under the strings
that had to pass THROUGH them. Other companies
utilized variations on this “pass through” scheme,
especially on so-called “lap steels.” Later, pickups
were placed under the strings (as opposed to around
the strings) and we still see that configuration on most
electric guitars today.
The energy imparted to the string by the player is
converted into an electric signal by the steel string’s
ability to change the pickup’s “MAGNETIC FIELD.”
As stated above, any device that changes one form of
energy (motion) into another form of energy (electricity)
is called a “transducer.” A guitar pickup changes
motion into electricity. While at the opposite end of the
“audio chain,” a loudspeaker changes electrical
energy into motion (sound) thus, completing the
process that we recognize as “electric guitar sound.”
It should be noted, that so-called “electric guitars”
must have strings made of materials that are capable
of causing a magnetic influence on the pickup’s
magnetic field. Generally, nickel and steel are used for
electric guitar strings. Nylon and bronze are also used
7
In the mid 30’s, production of “electric” Spanish guitars was introduced by a major American manufacturer using an odd combination of cobalt steel magnets. Though relatively inefficient, this pickup gained
considerable interest and is often called the “Charlie
Christian” pickup. While this was better than the previous “pass-through” variety that used “horseshoe”
magnets, the efficiency of the “Charlie Christian” pickup was marginal and was soon replaced by more efficient permanent magnet designs. This pickup is significant, because it was probably the first truly viable
Spanish guitar pickup to receive market acceptance
(which is the only reason we mention it here).
The very simplest form of magnetic pickup utilizes
a single so-called “magnet loaded” coil. Simply put,
this is a coil wrapped around a single “bar” magnet or
multiple “rod” magnets. This type of pickup has been
used on many guitars and is exemplified by so-called
“lipstick” pickups, as well as, numerous other pickups
used on many brands of guitars. Even today, so-called
“single coil” pickups are widely available on electric
guitars from many manufacturers. These pickups do
a reasonably good job of picking up the signal from
the strings, but often exhibit excessive “hum” when
in proximity to magnetic devices such as fluorescent
lighting, neon signs, and even the magnetic field from
the power transformer in guitar amps.
8
Today’s magnets are almost universally processed
using what is called “centerless grinding.” This process produces a fairly smooth and uniform surface,
ELIMINATING the desirability of using the beginning
(start) of the coil as ground. As mentioned above,
single coil pickups suffer from “noise problems” from
external devices, which is recognized as a very unmusical “buzz” at the frequency of the electrical mains.
A very simple way to minimize this involves changing
the traditional method of “polarizing” single coil pickups that need all the help they can get in “shielding”
the coil. Substantial improvements over “traditional”
methods can be gained by making the OUTSIDE (finish) of the coil GROUND and taking the OUTPUT off
the INSIDE (start) of the coil. By doing so, the OUTSIDE of the coil is literally at ground potential (i.e.,
shielded), while the INSIDE (start) part of the coil is
“shielded” and is the output. With today’s “centerless
ground” magnets and vastly improved electrical insulation for the wire, the old problems with wire shorting
out against the rough magnets are long past …YET,
most of Peavey’s competitors STILL do it the old way
and most STILL don’t use SHIELDED WIRE for the
output of the pickups or to wire up
the controls, etc, etc…Go figure???
“We Have Always Done It That Way”
An interesting note here is that the guitar and pickup
industry is unfortunately “plagued” by many “traditions” handed down from the guitar pioneers. Sadly,
these traditional practices are often NOT “good engineering” and SHOULD be changed!
As stated above, every magnetic pickup has a coil.
Every coil has a “start” and a “finish” as it is wound on
the coil former (sometimes called a “bobbin”). Many
of the early single coil pickups used “sandcast” magnets that had a fairly rough texture on their outside. For
economy’s sake, many of these single coil pickups
created the coil form itself by utilizing two “punched
fiber” pieces (often called “flatwork”) as the “ends”
of the coil former with the magnets themselves forming the central portion. Then, small gauge wire was
wound DIRECTLY on the magnets. Because the magnets themselves were crudely produced by a simple
“sandcasting” process, the outside of the magnets
were somewhat rough and could cause problems
when winding the old type “plain enamel” magnet
wire around the magnets themselves. In the early
days, it was thought that the “ground side” of single
coil pickups should be at the “START” of the coil, so
that IF the wire “shorted out” to the rough sides of the
magnet, such a “fault” would be “close to ground”
and therefore, minimally objectionable. Incredibly,
this early tradition has “lingered on” until today.
While on the topic of “strange old habits” that seemingly won’t die, another of our major competitors
STILL wires their guitars so that when BOTH pickups
are selected, turning down the volume on one pickup
causes the volume on the OTHER pickup to go down
too…Dumb! But after more than 40 years, they’re
STILL doing it that way! Another example of “tradition” winning out over “common sense” and good
engineering practice. Again, one can only wonder
WHY!
To Hum or Not to Hum
As referenced above, single coil pickups (the least
expensive) are prone to picking up extraneous noises buzzes, hums, electrostatic interference, etc, etc.
These problems plague nearly all single coil pickups
to some degree. There have been numerous methods
used to shield pickups from the two major forms of interference “MAGNETIC” (as we’ve discussed above)
and another troublesome type of interference
called “ELECTROSTATIC” (which is usually generated by some type of gas discharge lighting such as
florescent lights or neon signs). Electrostatic noise
can be effectively blocked by properly shielding the
pickup with a conductive substance such as a nonmagnetic metal (such as brass) or even a conductive
paint. Magnetic hum on the other hand, is somewhat
9
more difficult to prevent. One of the best methods yet
found, is to use very low impedance pickups (having
as little as one turn) which unfortunately require use of
a matching transformer (which in many cases defeats
the advantages of low impedance pickups both from
a technical and a cost standpoint).
“hum canceling” guitar pickup works in a somewhat
similar manner, using two coils that are 180° out of
phase.
If two pickup coils are mounted in a guitar, any magnetic interference coming in from the OUTSIDE will induce the SAME interference in BOTH coils! Because
the coils are connected out of phase, the interference
coming in will be canceled simply because the coils
are connected (180°) out of phase. I.e. if the interference induced into each coil is one volt, one of the
coils will produce 1 volt positive (+1V) while the other
produces 1 volt negative (-1V). When you add a positive 1 to a negative 1, the sum is ZERO! While this is
an overly simplistic explanation, it is exactly what happens in a “hum canceling” pickup. Because the coils
in most “hum canceling” pickups are arranged in series, the hum cancellation is not total (but is far better
than single coil pickups). Given that the coils for the
“hum canceling” pickups are out of phase and therefore, cancel each other out, one would naturally ask
how the pickup could work given that the coils cancel
each other…Good question, and one which very few
understand. The answer is fairly simple, but somehow
seems to “escape” many players and “guitar buffs.”
Early guitar amplifiers were relatively low powered,
used inefficient speakers, and featured just enough
gain to allow the guitar to function. Though noise,
hum, and buzz were problems; these negative effects
were not big problems. Later, as music demanded
louder performances, amplifiers became larger, more
powerful, and had more gain. Guitar builders were
searching for ways to make their product better and
they learned about “hum canceling” techniques utilized for decades by the telephone companies; who
used so-called “balanced coils” to cancel (buck) hum
induced into their telephone lines by adjacent electrical power lines. The so-called “hum canceling” guitar
pickup was introduced in a major way in the 1950s.
Incredibly, most players (and even most dealers)
don’t understand the basic principles of the so-called
“hum canceling” pickup. Balanced lines have been
used in the telephone industry (and in the broadcast
and recording industry) since their beginnings. The
same techniques were applied to guitar pickups and
this is why “hum canceling” pickups generally have
at least two coils. These coils are usually arranged so
that each coil is directly out of phase (180°) from the
other.
As described above, “hum canceling” pickups have
coils that are out of phase canceling any kind of EXTERNAL interference (magnetic fields, etc, etc.) which
comes into EACH of the two coils “in phase” or, as
engineers put it, in a “COMMON MODE.” This means
that the interference is COMMON (i.e. the same) in
both coils. Since the coils themselves are out of phase,
any “COMMON MODE” interference is canceled. Engineers call that effect “common mode rejection.”
Understanding the way this works is “half the story.”
The other half is simply that the MAGNETIC FIELDS in
each coil of the pickup are ALSO 180° out of phase.
If you look at the diagram on the next page, you will
see that the magnet in one coil has its NORTH pole at
the TOP, while the other coil has its SOUTH pole at the
TOP (i.e. the magnets are 180° out of phase also).
It is important to understand the concept of “phasing.” The simplest explanation is to think about flashlight batteries. If you have two flashlight batteries and
you connect the positive of one to the negative of the
other; then connect the negative pole of the second
battery to the positive pole of the first battery, each
battery will “cancel” the other (since they are 180° out
of phase). A voltmeter placed on these connected terminals (on either side) will read ZERO VOLTAGE simply because one battery is CANCELING the other! A
10
If the coils are out of phase, they CANCEL any interference coming in from the OUTSIDE. Because the
magnets are ALSO 180° out of phase, the result is
that 180°+180°=360° or 0. This simply means if you
reverse polarity once and then you reverse it again,
you end up EXACTLY WHERE YOU STARTED with
everything back IN PHASE as far as the INTERNAL
ACTION of the pickup (which is the only thing you’re
interested in feeding to your amplifier). Simply put, a
hum canceling pickup functions by combining TWO
180° out of phase systems. If you’re walking NORTH,
do a 180° turn, walk south, and then do another 180°
turn; you’re walking North again, just like when you
started walking North. That’s it! Nothing fancy, just
common sense. There are MANY VARIATIONS on
this theme however.
Total Tonality
Most of us recognize that different pickups produce
different tonalities. Almost everything about a pickup
influences the sound picked up from the strings. Because this is such a complex and contentious topic,
we’re going to discuss only the general principles.
Magnetic pickups “do their thing” using magnets
with an adjacent coil of wire. So far, we’ve seen several different configurations of pickups and the only
things common to all of these are magnets and a coil
of very fine wire; so before going further, we need to
understand a little bit about what happens when wire
is wound into a coil.
Most guitar players understand and accept that pickups produce different sounds; not only from single
11
coil and dual coil (hum canceling) but that the sound
also varies within these categories based on a number of factors. A most obvious factor is that a single
coil “senses” the string motion at one point (where the
pickup is located). It’s equally obvious (but not generally recognized) that a dual coil pickup senses the
vibration of the string at TWO locations on the string;
thus, contributing to the significantly different sound
of a hum canceling (dual coil) pickup from the tonality
of a single coil pickup.
fuse it with resistance. Without getting too complex,
suffice to say that impedance is “AC RESISTANCE”
and is measured in ohms. Resistance is DC and is
also measured in ohms. Inductance and capacitance
have virtually no effect in DC circuits, but have drastic
effect in AC circuits.
Coils of wire exhibit several important characteristics
that act together to influence the tonality of a pickup.
Everyone knows that wire has some amount of DC
resistance and many pickup manufacturers actually
specify the DC resistance of their coils (since this is
a very easy parameter to measure). When a wire is
wound into a coil, it creates two additional parameters that greatly effect tonality. A coiled wire exhibits
both INDUCTANCE and CAPACITANCE. The amount
of wire in the coil, the size of the wire, as well as the
coil’s geometry, greatly affect the inductance. Generally speaking, the more turns of wire in a coil, the
higher the inductance.
While guitar pickups are actually fairly simple devices, the variations in design and manufacture of guitar
pickups (and the reason that they sound the way they
do) is a most complex topic that we won’t attempt to
get into in this basic discussion of guitar pickups. It
is important to understand some of the “language of
electronics” to grasp the basic concepts. Essentially,
you should know that a coil of wire is (by definition)
an “inductor.” The schematic representation of an inductor is shown as figure A. In guitar circuits, inductors are usually used in conjunction with magnets or
polepieces, which are indicated in a schematic by the
inclusion of parallel lines next to the inductor symbol
(B). A capacitor is noted on a schematic diagram by
C (see below).
Another parameter, called capacitance, occurs when
conductors (wires) are placed in close proximity to
each other separated by an insulator. A coil (such as
used in a guitar pickup) exhibits both inductance and
capacitance, both of which play a big role in determining the pickup’s tonality.
Luckily, the only other component encountered in
most guitars are resistors, both fixed and variable
which are indicated by the symbols below, showing a
variable resistor (pot) and a fixed resistor. Obviously,
a variable resistor is nothing more than a fixed resistor arranged so that a sliding contact can change the
resistance as the center contact is moved. These controls are usually rotary, but can also be in a “linear”
form (slider).
Most of us understand, that speaker systems use socalled “crossover networks.” These frequency dividing networks utilize the bandpass characteristics of
both inductors and capacitors. Typically, capacitors
like to favor (pass) high frequencies, while inductors favor (pass) low frequencies. Most crossover
networks in speakers utilize combinations of capacitors and inductors to route the low frequencies to
the woofer and the high frequencies to the tweeter.
A “crossover network” does this by taking advantage
of the different bandpass characteristics of inductors
and capacitors.
Before going further, it’s important to know that the coil
of a guitar pickup is BOTH inductive AND capacitive.
This fact drastically influences the tonality of pickups.
Many people don’t understand impedance or con-
In a guitar pickup, many turns of small diameter wire
are utilized in order to generate enough signal (from
the vibration of the strings) to feed the amp. Every
magnetic pickup has a certain amount of inductance,
12
which is generally a “series” type phenomenon. Because the coil has a number of conductors wound
together, separated by the insulation on the wire, the
coil also has some amount of capacitance (which is a
parallel phenomenon).
“higher fidelity” and have more “bite” or edge than
so-called “induced magnet” pickups. Most hum canceling pickups tend to be of the “induced magnet”
type, while most single coils, tend to be of the “magnet loaded” type.
As in a crossover network, the inductance and the
capacitance work together to shape the frequency
response (bandpass) of the pickup. Inductors like to
pass lows, but not highs. Most pickups tend to have
some amount of high frequency degradation (rolloff) from its own inductance. The more inductance
(turns of wire) the more high frequency loss. At the
same time, the pickup coil’s capacitance also tends
to “shunt” (rolloff) high frequencies. Most players understand that if you put more turns of wire on a pickup
bobbin, you will get more output, but lose more high
end. The reason for this, is that more turns simultaneously gives you HIGHER INDUCTANCE AND HIGHER
CAPACITANCE (both of which tend to roll off the high
end).
As with most engineered products, there are usually
some exceptions and magnetic pickups have been
made in many, many different ways and have been
the subject of hundreds of patents. Generally speaking, most guitar pickups try to minimize excessive
inductance and “inter-winding” capacitance with different construction techniques in order to maximize
performance and minimize the detrimental qualities
of the inherent inductance and capacitance present
in all magnetic pickups. An example of this approach
is Peavey’s magnet loaded hum canceling pickup,
where we tried to maintain the “edge” or “bite” of a
single coil while maintaining the fullness and hum
canceling benefits of a dual coil pickup. These characteristics are further enhanced in Peavey’s magnet
loaded hum canceling pickup through the use of
Peavey’s patented pickup control system (US Patent number 4,164,163). This unique circuitry allows
the pickup to be operated in single coil mode or continuously changing to dual coil/hum canceling mode
through the unique use of a single pot (control).
Inductance is greatly affected by the physical structure of the pickup and adjacent magnetic metals,
polepeices, etc, etc. This is a major reason that pickup designers have come up with so many different
configurations of magnetic structures.
This circuitry was developed by Orville (“Red”) Rhodes, an old friend
of mine from California. This circuit
is exceptional because it doesn’t
use any active devices, batteries,
etc, etc; just a single capacitor and
a potentiometer put into the circuit
in a new and different way This circuit was so simple that most guitar builders (including myself) never
thought of it. Below are examples illustrating how a
single “pot” (control) changes the MODE of OPERATION from single coil continuously to hum canceling
(dual coil) to a high frequency rolloff. This circuit produces the WIDEST TONAL RANGE of any circuit we
have found, not using batteries.
Most players recognize the distinctly different tonalities available from single coil pickups compared to
the dual coil (hum canceling) variety. There are numerous reasons for this, but it is generally true that
so-called “magnet loaded pickups” tend to have extended high frequency response with an initial “edge”
on the attack that socalled “induced magnet pickups”
simply can’t produce.
If you compare a typical magnet loaded single coil
pickup to a typical induced magnet single coil pickup,
you will find that the induced magnet has a fuller “bell
like” quality, while the magnet loaded pickup tends
to have an “edgier” Hi-Fi type response. There are
reasons for this, which are complex and probably too
technical for this “primer” on guitar pickups. Generally speaking, magnet loaded pickups tend to have
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The advantage of this circuit (when used with
Peavey’s magnet loaded humbucker) is that in the
single coil mode, the “bite,” “edge,” and “attack” of
a magnet loaded single coil is easily obtained. As
the tone control (actually a mode control) is rotated
counter-clockwise, the “wiper” of the control (which
is grounded) moves further away from the “center
tap” of the pickup and therefore, the pickup gradually and CONTINIOUSLY becomes more and more of
a hum canceling dual coil pickup. Further rotation of
the tone/mode control results in high end rolloff similar to conventional guitar tone controls. Simply put,
in one unique pickup (accompanied by our patented
tone/mode control) we’re able to get the best of the
magnet loaded single coil sound through to (and including) the best hum canceling sound, using ONE
CONTROL that CONTINUOUSLY varies between
these operational modes. Many players resort to using different guitars to achieve these different tones,
but Peavey has succeeded in achieving this with a lot
of engineering and a little ORIGINAL thinking! This,
sadly, is somewhat rare in the field of guitar pickups.
Most pickup manufacturers (as well as guitar manufacturers) apparently concentrate most of their efforts on trying to duplicate “vintage” pickups from the
1950s. Peavey’s unique system has the best of the
old combined with the best of the new. We provide
this without batteries and without complications, while
allowing a smooth and CONTINUOUS change from
single coil to dual coil to high end rolloff. We believe
this system is the best available without having to use
on-board preamps, batteries, etc, etc. and is yet another reason we believe our guitars are the best!
Peavey Pickup Circuit Diagrams
Figure A shows the tone/mode pot in the single coil
mode. Please note, that the “center tap” between the
two coils (5) is effectively “grounded” by the wiper of
the tone/mode pot. With the “center tap” grounded, it
can be seen that coil “I” is essentially out of the circuit,
since its output is grounded, as is the bottom side of
the coil “II,” which is now operational in the SINGLE
COIL MODE because one end is grounded while the
other end provides the output. As the tone control is
rotated COUNTER-CLOCKWISE, the grounded wiper
moves further away from the center tap essentially
“un-grounding” that point; thus, PROGRESSIVELY allowing the coil “I” to operate as its output “sees” less
and less “loading” from the tone/mode pot. Because
the resistance of the tone/mode pot is high in relation to the impedance of the pickup, the LOADING
EFFECTS are continuously REDUCED as the pot is
rotated. At midpoint, the tone/mode pot ceases to
“load” the pickup and it becomes fully hum canceling (because both coils are now connected as a nor-
Although this system is very simple, I’ve found that it
helps greatly to explain how this simple circuit is able
to continuously vary the pickup from singe coil to
humbucking with a single pot. As you already know,
hum canceling pickups have at least two coils. These
two coils are almost always connected in series,
which means there is always a connection (jumper)
from one coil to the other. Since this “jumper wire”
is present in virtually every hum canceling pickup, it
provides an easy connection to the center of the two
coils often referred to as a “center tap.”
Peavey’s system utilizes the “center tap,” which is
brought out to one end (3) of the tone/mode pot. The
“wiper” (1) is grounded while the other end of the pot
(2) is connected to one side of a capacitor that is connected to the output.
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mal hum canceling pickup would be). Further rotation
of the tone/mode control brings the grounded wiper
closer to the tone cap (connected to the output) which
decreases high frequency response as in a conventional guitar tone control.
If you examine the operation of our tone/mode control, you can see that this fairly simple circuit has the
unique capability of continuously and incrementally
varying this unique pickup from a single coil, through
to a dual coil, to a high end rolloff. Previous circuits
have merely used a switch to ground the center tap,
enabling operation EITHER as a single coil OR a dual
coil. Our patented approach allows the player the option of singe coil, dual coil, high end rolloff, OR anywhere in between!
Incredibly, hundreds of books have been written about
guitars and dozens of books about amplifiers, but I’ve
never seen more than the most elementary discussion
about magnetic guitar pickups. Hopefully, this BASIC
DISCUSSION will be helpful in understanding how
pickups work. For reasons that I’ve never been able
to understand, guitarists want to believe that there is
“magic” in guitar pickups…Anything that we don’t
understand SEEMS to be “magic.” I wound my first
guitar pickup back in 1958, and long ago lost count of
how many since then. In all my years in this business,
I have NEVER encountered any “MAGIC”…Maybe a
fair amount of engineering, some art and science, but
no “magic.” Once you understand what a magnetic
pickup is (and how it works) you’ll be much better able
to get the sound that you’re looking for. Nobody has
ALL the answers (not yet anyway) and here at Peavey
we’re still continuing to look to the future instead of
spending all our time trying to “recreate the glories of
the past.” In any case, I hope this helps.
Hartley
P.S. A new book is available on the history of guitar
pickups. It is “Pickups” By Mario Milan and published by Centerstream/Hal Leonard Publications.
ISBN-10:1-57424-209-1
SAN 683-8022
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Innovation. Amplified.
Peavey Electronics Corporation • 5022 Hartley Peavey Drive • Meridian, MS 39305
Phone: (601) 483-5365 • Fax: (601) 486-1278 • www.peavey.com • ©2006 Printed in the U.S.A.