The history of popular music remains essentially the same as in our world until the popular Big Band music of the '40s gradually moved up in age demographic in the '50s, and became more and more Latin influenced. The younger kids of the early '50s embraced small band jazz - quartets, trios and quintets - as a more intimate reaction to the Big Band era, but by the middle of the decade, popular teen music was all about Rockout - a genre derived from the blues and country music, featuring loud steelbox guitars, simple vocals, standup bass, and trap drums in a heavy beat. Rockout would remain at the core of popular music until the present, though the sound changed every few years as new aspects were featured.
By the '60s, Rockout was cross-pollinating with other genres, becoming a mega genre which absorbed others. Some Rockout bands crossed with small band jazz to form Bopout, which heavily featured horns and syncopated beats. Jango was created when bands took on the Latin influences of popular Big Band music. The Glitz style featured complex shifting rhythms which were impossible to dance to, and elaborate polymelodic lines for all the instruments.
In the mid '70s, reaction to the overelaboration of rockout styles - particularly Glitz - triggered the inevitable backlash. A movement toward home-made instruments and simple, strong rhythms led to the Thunk movement. As percussion instruments are the easiest to create, most Thunk bands were heavily percussion oriented, which encouraged dancing. By the '80, Thunk bands were automating their music with flywheel-strummed steelbox guitars and extremely fast rhythms to make the Speed style. This in turn led to complete automation - machined designed and constructed to make musical sounds controlled by a single person. This movement was dubbed Mechanica, and became quite popular.
The Glitz style of Rockout eventually merged with Thunk and evolved into a new style called Loopout, which was created by control and manipulation of recording devices, particularly tape loops and record scratching rhythms. The loops were played through keyboards, where the speed of the loops could be varied to sound different tones. Anything - even percussion or machine noises - could be recorded and played back through these keyboards. Loopout is a studio-bound style, as the tape loops change their size depending on air temperature and humidity.