Tube amplifiers, also known as valve amplifiers, use vacuum tubes to amplify audio signals. They are popular in high-fidelity audio systems and among musicians for their warm, rich sound. The design of tube amplifiers often includes fewer components than solid-state amplifiers, which can contribute to their unique tonal characteristics. These amplifiers typically operate at higher voltages and can produce a natural compression effect when overdriven, making them desirable for electric guitarists. Brands like Marshall and Fender are well-known for their tube amplifier models, which are often favored for their vintage sound and aesthetic appeal.