The term professional audio has no precise definition, but it typically includes:
- Operations carried out by trained audio engineers
- The capturing of sound with one or more microphones
- Balancing, mixing and adjusting sound signals from multitrack recording devices using a mixing console
- The control of audio levels using standardised types of metering
- Sound signals passing through lengthy signal chains involving processes at different times and places, involving a variety of skills
- Compliance with organisational, national and international practices and standards established by such bodies as the International Telecommunication Union, Audio Engineering Society and European Broadcasting Union
- Setting up or designing sound reinforcement systems or recording studios.
Compared to consumer-grade audio equipment, professional audio equipment tends to have such characteristics as:
- Greater mechanical robustness and reliability
- Many more options for "tweakability" and modification than typical consumer grade equipment. For example, whereas a typical home audio grade active subwoofer may have a factory set-audio crossover to determine at which point the audio signal will be routed to the subwoofer and a factory preset phase control and equalizer setting, pro audio active subwoofers (with built-in amplifiers and electronics) may offer adjustable crossover points, user-selectable phase control and equalizer controls[a]
- Heavy-duty industrial-grade connectors, e.g. XLR balanced audio cables (for audio signals) rather than unbalanced cables and Speakon speaker connectors, rather than 1/4" speaker jacks
- Designed for touring and transportation. This includes the use of 19-inch rack-mount devices for electronic effects units and power amplifiers, the provision of handles and/or dolly wheels on heavy equipment to facilitate moving gear onstage (large speaker enclosure cabinets for subwoofers and sound reinforcement system main speakers typically have handles and wheels)
- Balanced audio interfaces (XLR) for lower noise and hum
- Higher analog audio signal levels of 0 dBu or more[3]
- AES/EBU digital audio interfaces
- Lower-noise audio equipment with less Total Harmonic Distortion
The broadcast quality of professional audio equipment is on a par with that of consumer high-end audio and hi-fi equipment, but is more likely to be designed purely on sound engineering principles and owes little to the consumer-oriented audiophile sub-culture.[4]
