When the same rhythmic beat is played repeatedly over a long crescendo, during which the music goes from simple and quiet to loud, blaring and borderline cacophonous. Similar to Variable Mix. Examples of Bolero Effect include: * Maurice Ravel's "Bolero" is the Trope Namer and Trope Maker. * "Abbadon's Bolero" by Emerson, Lake & Palmer. * "Ewigkeit" from Tanz der Vampire. * Carmina Burana, the suite whose "Fortuna Imperatrix Mundi" is the Trope Codifier for Ominous Latin Chanting, does this. * Done intermittently over the course of the second Dream Sequence of Lady in the Dark. The beat disappears for some fairly long stretches, though it sounds like "Bolero" tweaked into Common Time. * The repeated chorus of "Hey Jude" employs a very similar effect. * "In The Ha