Stopbar

A stoptail bridge (sometimes also called a stopbar bridge) used on a solid body electric guitar or archtop guitar is a specialized kind of fixed hard-tail bridge. Hard-tail bridged guitars use different bridges from those guitars fitted with vibrato systems (which are also known as tremolo arms or whammy bars).

The stoptail bridge consists of two parts: an adjustable fixed bridge piece, such as a Tune-o-matic and a separate stopbar (or stop bar) tailpiece.

A stopbar tailpiece is, as the name implies, a bar-shaped formed metal piece commonly made of pot metal or zinc alloys although aluminum and brass. Many manufacturers claim that the use of lightweight metals and alloys, such as aluminum, provide a greater transfer of the string's vibrational energy or "resonant quality" to the guitar body since there is less mass to excite. Aluminum was also used in the early examples of stoptail bridges from the 1950s, so it carries the mantle of "vintage" vibe.

The "stop" part comes from the fact that the string ends are held in place or they "stop" inside the bar. The bar is mounted on top of the guitar body usually by means of sturdy threaded metal studs screwed into threaded sleeves embedded into the body of the guitar. The studs and stopbar are located behind the separate bridge piece.

The stopbar can either simply slip onto notches on top of the studs, or be held in place using set screws. One danger to be aware of is that the stopbar can fall out of the notches when changing strings and put a ding in the guitar's finish. When it is held in place using the screws, it is sometimes referred to as a "locking stopbar". In these designs, the Tune-o-matic bridge section is also usually fastened to its embedded studs by set screws. This fastening of the key components in a stoptail bridge system is claimed to impart more sustain and tone to the guitar's sound.

The stopbar has holes drilled into it that allow the guitar strings to be threaded from the rear and out through the front. The string path then goes over the bridge saddles and the string nut to the machine heads located on the .

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Wikipedia