1920s–1940s
The bassists who first sought methods to make their instruments louder were upright bass players. While the upright bass is a large instrument, standing about six feet tall (with its endpin

Amplifiers may be based on tube ("thermionic" or in the UK, "valve") or solid state (transistor) technology, or hybrid designs that use both technologies, typically by pairing a tube preamplifier with a transistor power amplifer.
Tube amplification

Almost all bass amplifiers are designed for use with an electric bass, which has magnetic pickups. The signal from a double bass usually comes from a piezoelectric pickup mounted on the bridge or beneath the feet of the bridge. These pickups require a

Different types of equipment are used to amplify the electric bass and other bass instruments, depending on the performance setting, style of music, the sound desired by the bassist, the size of the venue and other factors, such as whether a bassist is an

The lowest note on the double bass or four-stringed electric bass is E1, two octaves below middle C (approximately 41 Hz), and on a five-string it is B0 (approximately 31 Hz).

Controls
There are two main types of controls on bass amps: switches and rotary knobs. The simplest, least expensive practice amps and combo amps

The basic sound of the amplified electric bass or double bass can be modified by electronic bass effects. Since the bass typically plays an accompaniment, beat keeping role as a rhythm section instrument in many styles of music, preamplifiers ("preamps"),