- A device which increases the strength of acoustic (sound) waves.
- An amplifier of signals that operates within the range of frequencies that humans can hear.
- A high-fidelity amplifier that operates within and beyond the range of frequencies humans can hear. For instance, such an amplifier may have a frequency response of 5 Hz to 100 kHz.
- A device which intensifies sounds by its shape. A horn is an example.
- synonymacoustic amplifier