The slang term for "PA" (public address) gear, or 'sound reinforcement'.
This term first became popular in 1960's Jamaica, in the reggae & dub
music scenes.
King Tubby was a pioneer in the usage of custom PA systems,
so was Lee Scratch Perry. In addition to the same formula that 'rock' systems use (two or more large "main" speakers, subwoofers, mixer,
microphones) dub "soundsystems" also utilize effects & devices for excessive
sound treatment (reverbs, delays, sound effect devices, samplers, effects units, etc)
This "dub" discipline carries on today, bands like Twilight Circus
Soundsystem &
Dead Panda Soundsystem hold the belief that an
artist is their own best engineer, too much is at risk with an 'outsider'
(hired PA/soundperson).
The customized nature of the modern "
soundsystem" underscores the importance of
sound quality to the dub &/or electronica artist.