sound system 
noun
A set of equipment for the reproduction and amplification of sound.The village society is appealing for more volunteers to help steward the event, particularly people with knowledge of sound systems and amplification....
- Other crews will bring their sound systems - turntables, microphones and speakers and voices.
- The concerts are free from artificial electric sound systems, microphones and loudspeakers.
- ultimately
- ultima Thule
- ultimatum
- ultimo
- ultimobranchial
- ultimogeniture
- ultisol
- ulto
- ultra
- ultra-
- ultrabasic
- Ultrabook
- ultra-careful
- ultracentrifugal
- ultracentrifugation
- ultracentrifuge
- ultra-clean
- ultracold
- ultraconservatism
- ultraconservative
- ultracrepidarian
- ultracritical
- ultradian
- ultra-fashionable
- ultra-fast