Tripath is a variation on class D amplifier where name comes from Tripath Amplifier Technologies (that went bankrupt few years ago).
SET = Single-Ended Triode amplifier a tube amplifier with only one (in opposition to push-pull) output tube operating in triode mode.
SET = Single-Ended Triode amplifier a tube amplifier with only one (in opposition to push-pull) output tube operating in triode mode.