In 1991, around one of their "revolutions" the ADAT was released[0]: "While synchronization had been available in earlier machines, ADAT machines were the first to do so with sample-accurate timing - which in effect allowed a studio owner to purchase a 24-track tape machine eight tracks at a time. This capability and its comparatively low cost, originally introduced at $3995, were largely responsible for the rise of project studios in the 1990s"<p>Technological revolutions that have lowered the costs of recording and distribution have often precipitated changes in the music itself. Not to mention the new capabilities introduced by new technologies like electric guitars, magnetic tape recording, sampling, digital recording, and whatever that robot-death-sounding thing that they keep doing in Dubstep is :)<p>[0] - <a href="http://en.wikipedia.org/wiki/ADAT" rel="nofollow">http://en.wikipedia.org/wiki/ADAT</a>