I think the Gravis Ultrasound is in the same category as the Apple IIGS sound card, which came out in 1986. And I put the Apple IIGS sound card much further ahead than the Amiga Paula.
The GUS (that kickstarted alsa on linux) is based on the DOC II (ES5504), which is more or less a 16-bit version of the DOC that could address 1MB of sound sample RAM.
VCF East: The Story of Ensoniq – Al Charpentier, Bill Mauchly, Joe Friel: When Bruce Crockett, Bob Yannes, Charles Winterble and Albert Charpentier left Commodore in late 1982, they named the company Peripheral Visions.
Listen as Albert & Bill will tell their tangled story of how they become Ensoniq.