is, without repetitions and tempo leaps. On the contrary, its melodic version requires fewer bytes if the rhythm is “perceived” as being repeated at a double tempo. Thus, the loop of interdependence of rhythm and tempo is overcome due to the simplicity criterion, which "optimally" distributes the complexity of perception between rhythm and tempo. In the above example, the repetition is recognized because of additional repetition of the melodic contour, which results in a certain redundancy of the musical structure, making the recognition of the rhythmic pattern "robust" under tempo deviations. Generally speaking, the more redundant the "musical support" of a rhythmic pattern, the better its recognizability under augmentations and diminutions, that is, its distortions are perceived as tempo variations rather than rhythmic changes: Modern classical music Twentieth-century classical music introduced a wide range of approaches to tempo, particularly thanks to the influence of modernism and later postmodernism. While many composers have retained traditional tempo markings, sometimes requiring greater precision than in any preceding period, others have begun to question basic assumptions of the classical tradition like the idea of a consistent, unified, repeatable tempo. Graphic scores show tempo and rhythm in a variety of ways. Polytemporal compositions deliberately utilise performers playing at marginally different speeds. John Cage's compositions approach tempo in diverse ways. For instance 4′33″ has a defined duration, but no actual notes, while As Slow as Possible has defined proportions but no defined duration, with one performance intended to last 639 years. Electronic music Extreme tempo More extreme tempos are achievable at the same underlying tempo with very fast drum patterns, often expressed as drum rolls. Such compositions often exhibit a much slower underlying tempo, but may increase the tempo by adding additional percussive beats. Extreme music subgenres such as speedcore and grindcore often strive to reach unusually fast tempo. The use of extreme tempo was very common in the fast bebop jazz from the 1940s and 1950s. A common jazz tune such as "Cherokee" was often performed at quarter note equal to or sometimes exceeding 368 bpm. Some of Charlie Parker's famous tunes ("Bebop", "Shaw Nuff") have been performed at 380 bpm plus. There is also a subgenre of speedcore known as Extratone, which is defined by music with a BPM over 3,600, or sometimes 1,000 BPM or over. Beatmatching In popular music genres such as disco, house music and electronic dance music, beatmatching is a