Mechanical

Devices For

The Guitar

By Tom

Accessories:

Expanding

’s Sound

Mulhern

Experimentation to produce an

electrically amplified guitar began in

the 1920s. Research into this new

field was sporadic, poorly funded, and, to

say the least, thankless. Even in the most

general of applications such as popular

music, the toils of electric guitar inventors

didn't start to pay off until the late 1930s.

when a few adventurous players—most

notably Eddie Durham and Charlie Chris-

tian—introduced the electric guitar to jazz.

Even then, little notice was paid to it (except

as a novelty), and as yet it was not generally

accepted or desired. Not until the latter half

of the 1940s did the electric guitar start to

reap rewards in the marketplace.

Almost parallel to the electric guitar's

development was the experimentation into

producing mechanically-induced vibrato on

the guitar. The idea was simple enough: to

be able to change the pitch of a note, or

notes, without having to change left-hand

fingerings. Vibrato is commonly achieved

on nonfretted instruments (violin, viola,

cello, etc.) simply by gently rocking the left-

hand finger (that is stopping the string) back

and forth, parallel to the string. Since the

guitar has frets, such a method of pitch var-

iation is impossible. Bending the guitar's

strings is the most common method of

achieving vibrato.

Bending the string increases tension, and

thus raises the pitch. By relaxing the bend,

the pitch is lowered. Among the problems

inherent in this method of changing pitch

are: (1) It’s impossible under normal condi-

tions to bend a note lower than the actual

stopped note, and (2) it's practically a feat

for a contortionist to bend more than two

strings. The first mechanical vibrato was

patented by Doc Kauffman in 1929. Kauff-

man. who later teamed with Leo Fender

[see GP. May '78] to form K&F (to manu-

facture electric steel guitars and amps) in

the mid-1940s, invented the Vib-rola, a vi-

brato designed originally for banjo and

acoustic guitar. By pushing or pulling on

the vibrato’s arm, which extended from the

tailpiece, a guitarist could alter the tension

on all the strings. Unfortunately, this first

vibrato didn’t quite set the world on fire.

but it did. however, influence the design of

nearly all future vibratos.

A decade after Kauffman’s Vib-rola was

patented. Paul Bigsby, a machinist, began

making vibrato tailpieces. From the first

custom models produced in his shop in

1939. he went on to create several commer-

cial vibratos. From such humble beginnings

evolved the largest vibrato tailpiece manu-

facturing company in the world. Bigsby

[3521 E. Kilgore Rd., Kalamazoo, Ml

49001], Paul headed the company until he

sold it to former Gibson president Ted Mc-

Carty [see GP, Nov, ’78].

The way Bigsby's vibratos work at first

appears complicated; however their opera-

tion is fairly simple. The tailpiece features a

pivoting cylindrical bar (called a string bar)

with six small pins sticking out of it to

accommodate the round, barrel-like ends of

the strings. This bar is held in the tailpiece

by two low-friction needle bearings (one at

each end). A lever attached to one end of

this movable bar is manipulated by the arm

that extends from the tailpiece. This arm is

mounted on a spring to keep the strings at

their correct tension when the bar isn't being

depressed. The spring also helps return the

bar to its resting position after it is pressed

down.

This basic configuration (with slight

technological improvements) was used on

all Bigsby vibratos that followed the early

prototypes. The addition of another stan-

dard Bigsby feature—a swing-away handle

—came in the 1950s after Gibson started

exclusively offering Bigsby vibrato tailpieces

on their factory-produced guitars in 1950.

Eventually, other guitar manufacturers, in-

cluding Gretsch, Guild. Kay. Vox. Silver-

tone, and Harmony, offered Bigsby-made

vibratos on their instruments. Even Fender

offered Bigsby vibratos on some of their

Telecasters between 1969 and 1972.

Several companies developed their own

vibratos. Among them were Rickenbacker.

with their Ac-cent vibrato (offered on their

375 series guitars), Gretsch, and Gibson.

On Gibson’s Firebird 111, V, and Vll

models, as well as on some SG’s, a variety

of Gibson-made vibratos were offered. The

tailpieces featured a plate through which

six strings ran. An arm for controlling the

pitch change was fastened directly to the

plate (the arm could swing away when not

in use). On some other Gibson solidbodies

offered in the 1950s. a side-pull vibrato was

used, but was soon abandoned when gui-

tarists showed little desire for a side-to-side

vibrato.

In 1954 Fender debuted the revolution-

ary Stratocaster, which had a built-in vi-

brato mechanism that differed drastically

from Bigsby's invention. The Stratocaster’s

bridge is attached to a large metal block set

into the body. The strings pass over the

bridge and through the block, which acts as

an anchor for them. Without the bridge

mounting plate that holds the bridge assem-

bly in place, the string anchor block would

float out of its mounting. Also, five springs

inside the body (accessible from the guitar’s

back) run between the string anchor block

and a plate held by two screws that fasten

to the body. These springs give the necessary

tension to balance the bridge so that proper

tuning can be achieved. By turning the

screws that hold the springs, overall tension

can be adjusted. In fact, many guitarists to-

day— particularly rock players — remove

two of the springs altogether, because their

lighter strings need less tension pulling

against them.

Fender introduced other guitars with

Mosnt es Jeature a number of vibrato styles: this

one entails individual roller bridges.

stock vibratos—the Jazzmaster in 1957. and

the Jaguar in 1962. Later, even more Fen-

ders with vibrato units were made: the

Mustang, the Antiqua II (a member of the

Coronado series), the Bronco, and the Bass

VI (6-string bass). On the Jaguar. Jazz-

master, and Bass VI vibratos, an added fea-

ture called the Trem-Lok was included to

make tuning easier. With most vibratos, the

interaction of the tension produced by the

vibrato springs and the strings makes tuning

a sometimes arduous process. Also, when a

string breaks on a guitar equipped with a

vibrato, the tension re-equalizes itself, gen-

erally resulting in out-of-tuneness. The

Trem-Lok is a piece of steel inside the vi-

brato mechanism that slides into place and

holds the pivoting portions of the unit in

place, so that tension changes aren’t allowed

to occur. The Trem-Lok can also be acti-

vated for songs in which the vibrato isn’t

being used (to assure that the vibrato won’t

Continued on next page

Rickenbacker vibrato tailpiece.

Early '60s Gibson vibro la, with rare ebony tail-

block and decorative in lav.

Bigsby made vibrato tailpieces in various styles

for several manufacturers, including Gretsch.

Leo Fender’s patent for the Stratocaster vibrato.

Strat vibrato (L-R): siring anchor block, tension springs, spring plate, adjustment screws...