Augustus Pablo -
King Tubby Meets Rockers Uptown (1976)
For those not in the know, King Tubby was a revolutionary producer and engineer who 'invented' dub music and the remix, and was the first of his kind to gain fame and respect on a par with recording artists (at least in Jamaica).
Augustus Pablo was another first, the first melodica instrumentalist to record an album. 'Rockers' was the name of his label, named after his brother's soundsystem.
So what you have here is Pablo banging out his tunes, playing all the keys, and overseeing production, before letting Tubby loose at the mixing stage doing what he did best - using the mixing desk as an instrument to earth-shaking effect. Loping basslines are brought to the fore, vocal snippets are phased in and out, elements are doused in reverb and other effects employed to create that atmosphere... it's saturated and heavy but lighter than air at the same time.