Full-range loudspeakers

Full-range loudspeakers - integrated
systems incorporating
woofer and tweeter (and, if used,
midrange) drivers in a single enclosure.
As the name implies, they are
designed to reproduce the full audio
range (more or less). In practical
terms, their range rarely extends
below about 60 Hz.

Tweeter loudspeakers

Tweeter loudspeakers - designed
to reproduce the highest frequencies
(normally higher than
1.5 kHz, and usually above 6 kHz).
If a cone-type driver is used, its diaphragm
diameter usually ranges
from 2 to 5 inches; compression
driver diaphragms range from
under 1.5 inches to about 4 inches.

Midrange loudspeaker

Midrange loudspeakers(
formerly called "squawkers,"
though this is an archaic term from
the hi-fi world) - designed specifically
to reproduce mid frequencies
(typically above 500 Hz). The highest
frequency reproduced by a
midrange unit is usually not higher
than 6 kHz. If a cone-type driver is
used as a midrange loudspeaker, its
diameter typically ranges from 5 to
12 inches; if a compression driver is
used, its diaphragm diameter may
range from 2.5 inches to 4 inches
(with a few special units up to about
9 inches in diameter).

Woofer loudspeakers

Woofer loudspeakers - designed
specifically to reproduce low frequencies
(usually below 500 Hz).
Woofers sometimes are used to
reproduce both low frequencies and
some mid frequencies (normally not
higher than 1.5 kHz). Typically,
cone-type drivers are used as woofers,
measuring from 8 to 18 inches
in diameter.

Optical Pickups

Optical Pickups - convert variations
in the density or transparent
area of a photographic film into an
audio signal. Used for most motion
picture sound tracks.

Laser Pickups

Laser Pickups - convert imprinted
patterns on a compact disc
into a digital data stream that is
then translated by a DAC (Digitalto-
Analog Converter) into an analog
audio signal.

Phonograph Pickups

Phonograph Pickups (cartridges)
- convert physical movement
of a stylus ("needle") into an
audio signal. In professional systems,
the moving-magnet type
cartridge is the most common.

Tape Heads

Tape Heads - convert fluctuating
magnetic fields (imprinted on
magnetic recording tape) into an
audio signal.

Magnetic Pickups

Magnetic Pickups - convert fluctuating
waves of induced magnetism
into an audio signal. Found on
electric stringed instruments.

Contact Pickups

Contact Pickups - convert sound
waves in a dense medium (wood,
metal, skin) into an audio signal.
Sometimes used on acoustic
stringed instruments such as
guitar, mandolin, violin, etc. Usually
of the crystal type, occasionally
capacitive.