Acoustic guitars are used in a variety of genres. Because of the long history of the acoustic guitar, there are many different kinds; some kinds are rarely considered guitars, such as the ukulele. The body of the guitar is large and hollow, allowing the sounds to resonate and providing a natural means of amplification. The sound of the acoustic guitar is characterized partly by a weak sustain, meaning notes will fade after being struck. However, some master-built classical guitars ("concert guitars") feature very good sustain and excellent overall performance.
Acoustic guitars are often used in performance. When the performance is in a personal setting or in an amphitheater an acoustic guitar can often be heard with no amplification. In most other performance scenarios amplification is required for the audience to be able to hear the guitar well. An acoustic guitar can be amplified by placing an amplified microphone near (possibly within several inches) the soundhole of the guitar or by installing an electric pickup in the guitar. An acoustic guitar with an installed electric pickup is not considered an electric guitar.
When we refer to acoustic guitars, we usually think of the 'flat top' guitar, with a distinctive soundhole. They are usually bigger than classical guitars(described below), and feature a somewhat thinner neck and metal(steel) strings. They come in a variety of sizes, from the smaller 'parlour' and 'concert' sizes, to the larger 'dreadnought' and 'jumbo' sizes with the most typical being the 'dreadnought'. They have a distinctive warm (although sometimes metallic) sound and can be strummed for playing rhythm in a wide range of popular music genres, including country, pop and rock, or played 'fingerstyle' for country blues, ragtime and folk. A plectrum or 'pick' can be used, for instance in the bluegrass 'flatpicking' style.
Unlike the electric guitar, the traditional acoustic guitar is not dependent on any external device for amplification. The shape and resonance of the guitar itself creates acoustic amplification. However, the unamplified guitar is not a loud instrument, that is, it cannot "compete" with other instruments commonly found in bands and orchestras, in terms of sheer audible volume. Many acoustic guitars are available today with built-in electronics to enable amplification.
The electric guitar is the workhorse of rock music, but has its uses in other genres such as blues, jazz and pop music. While an acoustic guitar can be played right off the rack, an electric guitar requires amplification (It is possible to hear an electric guitar without amplification for the purposes of practicing, but it will be much quieter than an acoustic guitar, and electric guitars are never played this way in performances.) The sound of an amplified electric guitar is very different from that of an acoustic guitar, even when no effects or distortion are used - the pickups and amplifier define the guitar's sound to a large extent. Like the acoustic guitar, the electric guitar has a poor sustain. However, amplification and especially overdrive will increase the apparent sustain, and feedback can allow a note to be sustained indefinitely, even for several minutes.
Technically speaking an electric guitar is any guitar with an electromagnetic pickup to amplify the sound created by the vibration of the strings. Electric guitars come in a variety of shapes and sizes which are not always limited to the acoustical qualities of the shapes and thus can be more comfortable to play. Electric guitars are typically easier to play since the strings usually are much thinner (the strings do not have to resonate as much as with an acoustic), and are closer to the neck, requiring less force to press them down. The multitude of variations amongst these guitars allow them to have a vast variety of different tones. The two most popular basic shapes of electric guitar are the Stratocaster style and the Les Paul style. Most electric guitars are solid body create very little sound on their own and therefore require an amplifier for all performance purposes.
Solid Body guitarsEdit
The typical electric guitar is a solid body guitar. They are called solid body because they are made from one solid piece of wood(or several pieces of wood glued together) and have no soundhole or obvious body cavities. With no soundhole to project the sound they make very little sound on their own and therefore require an amplifier for all performance purposes.
Archtop guitars began life as acoustic instruments favoured by jazz guitarists. Typically a curved 'violin' style body with metal string anchor at the base of the guitar. This acoustic archtop style can be obtained from a few specialist luthiers but it was the addition of pickups that really created the special sound which comes from the hollow body cavity resonance.
Some solid body electric guitars are described as archtop guitars based on their contoured body shape but this is stretching the term too far. Archtop guitars have been particularly popular in jazz music. Part of the smooth but taut jazz tone is the continued use of heavy gauge strings where modern guitarists opt for lighter playing and brighter sounding strings. The other musical style to favour archtops is rockabilly, a form of rock'n'roll with fast bluegrass type picking. Due to internal body strenghtening the unamplified sound of these is typically quieter than an acoustic guitar.
A distinction could be made between archtops with a full open body cavity and those like Rickenbackers where the body is thin and internal cavities minimal. These are sometimes called semis but with some models even using half solid, half hollow these should be considered on their own merits.
The electric hollow body archtop guitar can give a distinctive sound among electric guitars.
Twelve string guitarsEdit
The twelve string guitar is available as either an acoustic or an electric guitar. Twelve string guitars consist of two sets of six strings on the same neck with the first set being tuned normally and the second set being tuned one octave higher.The exception being the high B and E strings which are tuned to each other at the same octave. So tuning is typicaly Ee Aa Dd Gg bb e'e'
They are played in the same fashion as a six string guitar due to the strings being paired close together. However; playing them is slightly more difficult than a six string guitar because of the additional pressure required to depress two strings rather than one. It is also more difficult to bend notes harmonically.
The steel guitar is distinctive in being played horizontally, either across the players knees or on its own legs. There are two main varieties of the instrument, which is played using the metal slide, or 'steel', from which the guitar takes its name. The steel is held in the left hand, when used by a right-handed player. The two main variations are the lap steel guitar, which typically has six strings, and the pedal steel guitar, which can have more - and sometimes two or even three separate sets, each tuned differently. Pedals and knee levers are used to alter the tuning on particular strings whilst playing which, along with the sliding action of the steel, gives the pedal steel its distinctive voice, most often heard in country music and western swing.
Often mistakenly referred to as 'steel' guitars (some models have metal bodies), the acoustic resonator guitar is distinctive in not having a regular soundhole, but a large - usually circular - plate which conceals the resonator cone. The cone closely resembles an audio loudspeaker, though made from spun aluminium. The bridge of the guitar is connected either to the centre of the cone or to the edge (by an aluminium 'spider'), and the strings' vibrations are thus amplified and projected outwards through the perforated plate on the guitar's top. The most common resonator guitars have a single cone, although the original model (the tri-cone) has three. Resonators possess a loud, bright voice, making them easily heard in a large room or in the open air. They are popular with blues musicians, and country players. They can be played in the conventional style, or with a metal or glass slide.
Bass guitars have similar design features to other types of guitar but scaled up: thicker strings, longer neck and larger body, etc. This allows lower notes to be created when the strings are tuned to a playable tension. Although there are many variations, the standard bass guitar has four strings tuned EADG, one octave lower than the bottom four strings of a guitar in standard tuning. Although the bass guitar can be played like an oversized guitar, it also draws much inspiration from double basses and the instrument has a vocabulary of playing styles and music all of its own.
Seven string GuitarsEdit
Seven string guitars are examples of an electric guitar with an added low string, typically a B string, to give standard tuning of BEADGbe. They are allow for a bassier sound with more grunt without the need to down tune the guitar. The seven string is mostly seen in metal playing though belived to have originated in jazz