An audio engineer (also known as a sound engineer or recording engineer) helps to produce a recording or a live performance, balancing and adjusting sound sources using equalization and audio effects, mixing, reproduction, and reinforcement of sound. Audio engineers work on the "...technical aspect of recording—the placing of microphones, pre-amp knobs, the setting of levels. The physical recording of any project is done by an engineer ... the nuts and bolts." It's a creative hobby and profession where musical instruments and technology are used to produce sound for film, radio, television, music, and video games. Audio engineers also set up, sound check and do live sound mixing using a mixing console and a sound reinforcement system for music concerts, theatre, sports games and corporate events.

Alternatively, audio engineer can refer to a scientist or professional engineer who holds an engineering degree and who designs, develops and builds audio or musical technology working under terms such as acoustical engineering, electronic/electrical engineering or (musical) signal processing.

An audio engineer is proficient with different types of recording media, such as analog tape, digital multi-track recorders and workstations, and computer knowledge. With the advent of the digital age, it is increasingly important for the audio engineer to understand software and hardware integration, from synchronization to analog to digital transfers. In their daily work, audio engineers use many tools, including:

  • Tape machines
  • Analog-to-digital converters
  • Digital-to-analog converters
  • Digital audio workstations (DAWs)
  • Dynamic range compressors
  • Audio data compressors
  • Music sequencers
  • Signal processors
  • Microphones
  • Preamplifiers
  • Mixing consoles
  • Amplifiers
  • Loudspeakers