I would say that it's a different quality of pleasure: quieter, more subtle
ἡσυχία (hēsykhia) "Stillness, rest, quiet" (see my other post where Epicurus uses this exact word).
Trivia: Hesychia was also "In Greek mythology, either the daemon personification of silence, a handmaiden of the god of sleep, Hypnos; or a mortal daughter of Thespius."