Amplifiers are used by musicians in practice, rehearsal and at gigs. There are amps that can handle all three, or you can have a practice amp and a performance amp, whatever works for you and your band. Different than stereo amplifiers, a electric guitar
or bass amp does not just reproduce the sound created by the instrument, it adds color and tone and shapes the sound. A guitar amp allows your music to be heard, but more than that it can help you shape your musical sound. There are amps that are associated with blues, jazz, rock and metal. Selecting the amp that works best for you and your style will let your creative side free.
A guitar amplifier with effects means that you can set the 'tone' to create effects like tremolo, reverb or delay, dial in a sound best suited to metal, jazz or rock, or to imitate a famous amp sound such as Fender Tweed, British Stack and more. Smaller guitar amplifiers are suitable for practice and home use while the medium and larger amps have enough power to transition between home, rehearsals and gigs. Amp 'entertainment centers' often feature pre-recorded rhythm or instrument tracks to use for practice or recording.
For the electric bass guitar
, you need a bass amp. The low-frequency sounds produced by the bass require a specific design to handle the higher sound pressure levels. Generally these amps are more sturdily built with larger loudspeakers. Smaller than historic bass amplifiers, today's amps and combo amps are portable and flexible going from rehearsal to performance without trouble.