The Tremoloa is a stringed instrument belonging to the extended guitar zither family

Guitar zither

The guitar zither is a musical instrument consisting of a sound-box with two sets of unstopped strings...

, produced in America in response to the rapid increase in popularity of Hawaiian music

Music of Hawaii

The music of Hawaii includes an array of traditional and popular styles, ranging from native Hawaiian folk music to modern rock and hip hop. Hawaii's musical contributions to the music of the United States are out of proportion to the state's small size. Styles like slack-key guitar are well-known...

 during the 1920s

1920s

File:1920s decade montage.png|From left, clockwise: Third Tipperary Brigade Flying Column No. 2 under Sean Hogan during the Irish Civil War; Prohibition agents destroying barrels of alcohol in accordance to the 18th amendment, which made alcoholic beverages illegal throughout the entire decade; In...

, and continuing to be produced until the 1950s

1950s

The 1950s or The Fifties was the decade that began on January 1, 1950 and ended on December 31, 1959. The decade was the sixth decade of the 20th century...

.

The Tremoloa simulates the tonal effects

Timbre

In music, timbre is the quality of a musical note or sound or tone that distinguishes different types of sound production, such as voices and musical instruments, such as string instruments, wind instruments, and percussion instruments. The physical characteristics of sound that determine the...

 of the Hawaiian steel guitar

Steel guitar

Steel guitar is a type of guitar or the method of playing the instrument. Developed in Hawaii in the late 19th and early 20th centuries, a steel guitar is usually positioned horizontally; strings are plucked with one hand, while the other hand changes the pitch of one or more strings with the use...

 by passing a weighted roller

Wheel

A wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center, facilitating movement or transportation while supporting a load, or performing labor in machines. Common examples found in transport applications. A wheel, together with an axle,...

 stabilized by a swinging lever

Lever

In physics, a lever is a rigid object that is used with an appropriate fulcrum or pivot point to either multiply the mechanical force that can be applied to another object or resistance force , or multiply the distance and speed at which the opposite end of the rigid object travels.This leverage...

 termed a bar or arm, along a melody string

Monochord

A monochord is an ancient musical and scientific laboratory instrument. The word "monochord" comes from the Greek and means literally "one string." A misconception of the term lies within its name. Often a monochord has more than one string, most of the time two, one open string and a second string...

 and creating a tremolo

Tremolo

Tremolo, or tremolando, is a musical term that describes various trembling effects, falling roughly into two types. The first is a rapid reiteration...

, an effect

Sound effect

For the album by The Jam, see Sound Affects.Sound effects or audio effects are artificially created or enhanced sounds, or sound processes used to emphasize artistic or other content of films, television shows, live performance, animation, video games, music, or other media...

 which also gives rise the instrument's name. The instrument also possesses four chords

Chord (music)

A chord in music is any harmonic set of two–three or more notes that is heard as if sounding simultaneously. These need not actually be played together: arpeggios and broken chords may for many practical and theoretical purposes be understood as chords...

, to strum

Strum

In music, a strum or stroke is an action where a single surface touches several strings of a string instrument, such as a guitar, in order to set them all into motion and thereby play a chord...

 out the harmony

Harmony

In music, harmony is the use of simultaneous pitches , or chords. The study of harmony involves chords and their construction and chord progressions and the principles of connection that govern them. Harmony is often said to refer to the "vertical" aspect of music, as distinguished from melodic...

.

The patent for the Tremoloa was granted in 1932 to Harold Finney and John H. Large.