Sound Waves

An electronic music speaker, guitar amplifier or sound system.

Amplifier Or Speaker

A rectangular electronic music speaker, guitar amplifier or sound system with two round shapes, a big one and a small one.

A volume icon for sound control represented by a basic speakerphone with sound waves. 

A front-facing smartphone with three icons at the bottom of its screen: a video camera, a camera and a sound button.

A busy and overworked manager or employee surrounded by charts, graphs, and notifications.