Electric bass guitars require external amplification in much the same way that standard electric guitars do - and for the same reasons. There are several electric bass guitars with a hollow body, similar to that found on acoustic guitars, and this helps to provide some extra tone to the voice. However, electric bass guitars still require external amplification to be heard, and to provide the voice which is required.
There are two basic types of amplifier that can be used by those who play electric bass guitar. The first of these is the combination or 'combo' amplifier, and this has the amplifier unit and the speaker built in to one unit. Typically this is a large, often black unit with a large speaker grill at the front, and the amplifier unit built in to the top layer, with the buttons, dials and switches at the front. The second kind of amplifier is one where the speakers are entirely separate, and the amplifier connects the guitar and the speakers through its own system.
For beginners and those on lower budgets the combination amplifier unit is an excellent choice, and has proven to be very popular amongst players for many years. It offers versatility with convenience, and often these units are built to be portable, with carry handles built in to the top of the box, and allows them to be carried without fear of being easily damaged. On the other hand, for the more experienced player the separate amplifier and speakers arrangement provides the choice of each - giving more versatility and greater freedom of choice when it comes to each individual piece of equipment. Some guitarists prefer certain types of amplifier, or amplifiers that provide specific features that may not be found on the more generic combination units.
When it comes to recording electric bass guitars, this is often achieved by completely by-passing the amplifier, and instead connecting the guitar directly in to the sound recording equipment, and then providing external amplification from this. By setting the guitar up in this way, a truer sound quality is produced, rather than recording acoustically a sound which has been created electronically. This is for much the same reason as electronic keyboards are recorded in the same way, as the external speakers may hinder or reduce the eventual quality. Recording the electric bass guitar by directly connecting it to the sound recording equipment also provides the artist and the studio to create and apply extra effects, possibly digitally, by directly manipulating the original electric signal. This helps to ensure that there is no degrading of the quality, as well as providing even greater flexibility.
In addition to amplifier units there are also such items as pre-amplifiers which can also be used to apply certain effects, or alter the voice of the guitar in some specific way. For example, pre-amplifiers can sometimes be used to affect the way a guitar sounds, helping to re-create the sound of a different brand of guitar, such as older models or those used within specific branches of music.