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TIP, RING and SLEEVE (TRS) JACK CONNECTORS
A TRS connector (tip, ring, sleeve)
also called an audio jack, phone plug, jack plug, stereo plug, mini-jack, or
mini-stereo, and more recently MP3 jack is a common audio connector. It is
cylindrical in shape, typically with three contacts, although sometimes with
two (a TS connector) or four (a TRRS connector or mini RCA plug).
It was invented for use in telephone switchboards in the 19th century and is
still widely used, both in its original 1/4? (6.3 mm) size and in miniaturized
versions 1/8? (3.5 mm) and 3/32? (2.5 mm). The
connector's name is an initialism derived from the names of three conducting
parts of the plug: Tip, Ring, and Sleeve – hence, TRS.
In the UK, the terms jack plug and jack socket are commonly used for the respectively
male and female TRS connectors.
In the U.S., a stationary (more fixed) connector is called a jack. The terms
phone plug and phone jack are commonly used to refer to TRS connectors,but are
also sometimes used colloquially to refer to
RJ11 and older telephone plugs and the corresponding jacks that connect wired
telephones to wall outlets. (The similar terms phono plug and phono jack refer
to RCA connectors though both plug types
are used in tandem when a computer or MP3 player connects to a stereo.) To unambiguously
refer to the connectors described here, the diameter or other qualifier is often
added, e.g. quarter-inch phone
plug, 3.5 mm phone jack, and balanced TRS jack or stereo phone plug for the
most common uses of the three-contact version.
Modern TS and TRS connectors are available in three
standard sizes. The original 1/4 inch (6.35 mm) version dates from 1878, for
use in manual
telephone exchanges—making it possibly the oldest electrical connector standard
still in use. The 3.5 mm (1/8th inch approx), 2.5 mm (3/32 inch approx) or
sub-miniature sizes were originally designed as two-conductor connectors for
earpieces on transistor radios. All three sizes are now readily
available in two-conductor (unbalanced mono) and three-conductor (balanced mono
or unbalanced stereo) versions.
Four and five conductor versions of the 1/8 inch plug are used for certain applications.
A four conductor version is becoming a de facto standard output
connector for compact camcorders, providing stereo sound plus a video signal.
This interface is also seen on some laptop computers and on the
second-generation iPod Shuffle. Proprietary interfaces using both four and five
conductor versions exist, where the extra conductors were used to
supply power for accessories. There is also an optical connector used for TOSLINK
(mainly on things like portable equipment; hi-fi separates and
similar tend to use the standard square connector) that is the same size as
a 1/8 inch jack. Sockets exist that can make either an optical connection to
such
a plug or an electrical connection to a stereo jack plug. These combination
electrical/optical output jacks are present on all Apple Macbook,
Macbook Pro and Intel iMac computers
The iPod uses a TRS connector (left) while the iPhone
uses a TRRS connector (center) for its headset (microphone and control button
right).
A three- or four-conductor version of the 3/32? (2.5 mm) plug is widely used
on cell phone handsfree headsets, providing mono (three conductor) or stereo
(four conductor) sound and a microphone input.
Common stereo headphones with the 3/32? plug are often not compatible with this
type of socket. A 1/8? (3.5 mm) version of this plug is now commonly available
on mobile telephones as well. A 1/8?
stereo-plus-mic plug is available that is compatible with standard 1/8? stereo
headphones.
Although relatively unknown in modern electronics, the professional audio world
and the telecommunication industry rely heavily on tiny telephone (TT) connectors
which use mid-size phone plugs with a
4.4 mm (0.173-inch) diameter shaft. In the telecom world, this is known as a
"bantam" plug. Due to their compactness and reliability, TTs are often
used for professional console and outboard patchbays in
studios and live sound applications, in which a single patch panel may require
hundreds of patch points in a limited space. The TRS versions of TT connectors
are capable of handling balanced line signals
and are preferred in pro audio installations.
Both two-conductor and three-conductor versions of the three standard sizes
are readily available in male and female inline versions, and panel-mounting
female versions. Panel-mounting male versions of
these also exist but are rare, as they are vulnerable to mechanical damage and
therefore unreliable. Female inline versions are also notoriously unreliable
and are avoided by many users.
The most common arrangement remains to have the male plug on the cable and the
female socket mounted in a piece of equipment: the original intention of the
design. A considerable variety of line plugs
and panel sockets is available, including plugs suiting various cable sizes,
right angle plugs, and both plugs and sockets in a variety of price ranges and
with current capacities up to 15 amperes for certain
heavy duty 1/4? versions.
Less commonly used sizes, both diameters and lengths, are also available from
some manufacturers, and are used when it is desired to restrict the availability
of matching connectors, such as .210 inch inside
diameter jacks for fire safety communication jacks in public buildings, the
same size found in vintage 16 mm projector speaker jacks.[7]
A dual 310 patch cable, two-pin jack plug