Yet the laboriously sought musical epiphany rarely compares to the unsought, even unwanted tune whose ambush is violent and sudden: the song the cab driver was tuned to, the song rumbling from the speaker wedged against the fire-escape railing, the song tingling from the transistor on the beach blanket. To locate those songs again can become, with age, something like a religious quest, as suggested by the frequent use of the phrase "Holy Grail" to describe hard-to-find tracks. The collector is haunted by the knowledge that somewhere on the planet an intact chunk of his past still exists, uncorrupted by time or circumstance.