Pickup

There are several types of pickups:
Magnetic pickups work with metal strings and catch string's movements using a magnetic field created my a magnetic coil. These are most common with electric guitars.
Piezo-electric pickups use somewhat different approach and are more often used with acoustic instrumets.
Optical pickups are a new wave of pickups developed by one company and are currently not widely used. Yet they promise to be better than other types of pickup because of their clear sound and accurate representation of string vibrations.

The pickup would work just as well in an airless chamber. The string would produce no sound, but the pickup would convert the change in inductance into an electrical signal representing the sound waveform just the same.

Pick"-up, or Pick"up` , n. [Colloq., Cant. or Slang]

1.

Act of picking up, as, in various games, the fielding or hitting of a ball just after it strikes the ground.

2.

That which picks up; specif.: (Elec.)

= Brush b.

3.

One that is picked up, as a meal hastily got up for the occasion, a chance acquaintance, an informal game, etc.

© Webster 1913