Acoustic guitarists are always looking for ways to improve sound projection while maintaining the instrument’s distinct tones. They use an acoustic guitar amplifier as one of the methods to accomplish this task. Amplifiers, which were once primarily used for electric musical instruments, help to expand the sound of a guitar so that it can fill large rooms or concert halls. Acoustic amplifiers come in a variety of sizes and shapes, ranging from large stage equipment to smaller devices designed for more intimate settings.
Despite the popularity of electric guitars, many musicians perform with acoustic instruments and must ensure that the sound is distributed evenly throughout the venue. During the latter half of the twentieth century, musical equipment manufacturers introduced a variety of acoustic amplifiers to meet this demand. For performances, most musicians use a preamp as well as a large amplifier and speaker setup. Preamps eliminate unwanted feedback and may or may not provide a variety of reverb options to the user. Larger amplifiers amplify or boost the sound of the instrument and project it across large spaces.
A good speaker system and power amps connected to built-in acoustic guitar components work together. Hard rock musicians may want to boost sound and add special effects at the same time, whereas bluegrass, country, and folk musicians prefer amplifiers that retain the clean, natural sound of acoustic guitar. With this in mind, most modern amplified sound systems offer users a variety of ways to customize the sound of an acoustic guitar amplifier. These effects could include distortion, feedback control, and equalization, in addition to reverberation.
Acoustic guitar amplifiers can also be made with magnetic pickups attached to the instrument. Soundhole pickups, which are mounted inside the soundhole of the guitar, detect and amplify string vibrations, but they can also amplify distortion and produce a more electric sound. Contact pickups, such as piezoelectric pickups, or piezos, attach directly to the structure of the guitar and detect movement or vibrations, which are converted to an electric signal. Piezoelectric crystals detect vibrations and remain a popular amplification choice for acoustic guitar players.
Musicians can also try to achieve acoustic amplification attaching electrical devices to their guitars known as transducers. A simple microphone strategically placed can be used as an acoustic guitar amplifier on a low budget, but the output is typically unreliable and of poor quality. Transducers attached to the guitar are a better solution. Dynamic microphones use a wire coil connected to a diaphragm to amplify sound, resulting in electrical sound signals. Dual-conducting plates and internal circuitry in condenser microphones amplify sound when electrically produced currents transform into voltage signals.