Clavia electro 2 Guida Utente

9. H

ISTORY

T

HE

 

STORY

 

BEHIND

 

THE

 E

LECTRO

 2 

INSTRUMENTS

The Nord Electro 2 is a stage keyboard focused on vintage instrument sounds -- specifically, sounds from 
popular electromechanical keyboards produced from the '50s to the '70s. These instruments are no longer 
in production, but they continue to play a remarkably important role in music today. In this chapter, we 
will focus on these instruments. For those of you who aren't familiar with these instruments, we will give 
you a description of the principals of each instrument and its basic design theory, as well as short histories 
of the instruments. For all of you interested in digging even deeper into these instruments, we will recom-
mend some nice literature to read further about them (see the end of this chapter).

W

HAT

 

IS

 

AN

 ‘

ELECTROMECHANICAL

’ 

INSTRUMENT

?

One in which some sort of electric pick-up system, either electromagnetic or electrostatic, detects and am-
plifies certain mechanical movements. The source of these movements can be a spinning tone wheel or the 
vibrations of a reed, string, or tine.

H

OW

 

DOES

 

AN

 

ELECTROMECHANICAL

 

PICK

-

UP

 

WORK

?

The pick-up system in a Electric Piano is electromagnetic. When you play a note on a Electric Piano, a 
metallic tine vibrates and changes the magnetic field around a coil that picks up the vibration. These vi-
brations are slightly amplified to create a musical tone. 

The Hohner Clavinet has real strings inside. The vibrations of each string are picked up by an electromag-
netic pick-up similar to the magnetic pick-ups of an electric guitar. 

An electromagnetic pick-up system is also used in tone wheel Hammond organs such as the famous B-3. 
A tone wheel is a rotating disc with notches around its edge. Positioned as close as possible to each of the 
96 tone wheels in a B-3 is a magnetic pick-up. Every time a notch passes the pick-up, a change will occur 
in the magnetic field, which will induce a small voltage in the pick-up. The number of notches in the wheel 
and its rotation speed determine the pitch of the tone produced.

Wurlitzer electric pianos uses an electrostatic pick-up system. A DC voltage is applied between vibrating 
reeds and a metal plate placed near the end of the reed. As the reed vibrates, it varies the capacitance be-
tween the metal plate and the reed. These changes will generate an electrical signal - the tone (see the sche-
matic figure to the right).