Catch Triforce Fanfare
After Link slugs his way through the bowels of an underworld and defeats to beastly boss, he finds his way into the Triforce Room to collect an 8th piece of the Triforce of Wisdom. When he holds the Triforce shard on high, you are rewarded with the Catch Triforce Fanfare. It's a happy little ditty that motivates you to continue your quest.
The title comes from the Famicom 20th Anniversary - Original Sound Tracks, Vol.1 album. The song is track 6 in the NSF file.