Semi-acoustic

A semi-acoustic guitar or hollow-body electric is a type of electric guitar that originates from the 1930s. It has both a sound box and one or more electric pickups. This is not the same as an acoustic-electric guitar, which is an acoustic guitar with the addition of pickups or other means of amplification, added by either the manufacturer or the player.

In the 1930s guitar players and manufacturers were attempting to increase the overall volume of the guitar, which had a hard time competing in loudness with other instruments—especially in large orchestras and jazz bands. This led makers to try a series of designs that focused on amplifying a guitar electrically through a loudspeaker. In 1936, Gibson made their first production run of electric guitars. These guitars, known as ES-150s (Electric Spanish Series) were the first manufactured semi-acoustic guitars.

Gibson based them on a standard production archtop, with f holes on the face of the guitar's soundbox. This model resembled traditional jazz guitars that were popular at the time. The soundbox on the guitar let limited sound emit from the hollow body of the guitar. These guitars, however, could be electrically amplified via a Charlie Christian pickup, a magnetic single-coil pickup that converted the energy of the vibrating strings into an electrical signal. The clear sound of the pickups made the ES series immediately popular with jazz musicians. The first semi-acoustic guitars are often thought of as an evolutionary step in the progression from acoustic guitars to full electric models.

However, Gibson made the ES-150 several years after Rickenbacker made the first solid-body electric guitar. The ES series was merely an experiment the Gibson company used to test the potential success of electric guitars. The experiment was a successful financial venture, and the ES series is often referred to as the first successful electric guitar. The ES-150 was followed by the ES-250 a year later, in what became a long line of semi acoustics for the Gibson company.

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