of American company Chamberlins brings two of their musical instruments to England to search for someone who could manufacture 70 matching tape heads for future Chamberlin keyboards. Fransen approaches a UK company that is skilled enough to develop the idea further and a deal is struck with Bradmatic Ltd. The first Mellotron sample keyboards are manufactured in Aston and are to enjoy great longevity in the music industry. Alongside the Hammond organ, the Mellotron later becomes a seminal musical instrument for music genres such as rock and psychedelia, it is also crucial to shaping the sound of the progressive rock and hard rock groups of the 1970s as well as inspiring further development of the sample keyboard, most notably the Fairlight, which, in turn, inspired sample modules such as the Akai Sampler range; synonymous with hip hop and dance music. Some of the more notable songs that make use of the signature Mellotron sound include Nights In White Satin by The Moody Blues, Tomorrow Never Knows and Strawberry Fields Forever by The Beatles, 2000 Light Years from Home and We Love You by The Rolling Stones, Hole In My Shoe by Traffic, Mercy Mercy Me by Marvin Gaye, Days by The Kinks, Space Oddity by David Bowie, Stairway to Heaven, The Rain Song and Kashmir by Led Zeppelin. 1965: The Birmingham Press and Mail installs the GEC PABX 4 ACD, the earliest example of a call centre in the UK. Already the hallmarks of the call centre can be seen in the rows of agents with individual phone terminals, taking and making calls. 1969–1970: Heavy metal music begins to take shape in Britain and America. Of the earliest influential bands that are later to be described as Heavy Metal, several of the most notable artists arise from the mid to late 1960s Brum Beat music scene, such as: Robert Plant and John Bonham of Led Zeppelin, Ozzy Osbourne, Tony Iommi, Geezer Butler and Bill Ward of Black Sabbath and Rob Halford and Glenn Tipton of Judas Priest. During the later half of the 20th century the first trials of the combined oral contraceptive pill outside the USA take place at Birmingham University and extensive research into advanced allergy vaccines and the synthesis of artificial blood take place. 1975: Birmingham inventor Michael Gerzon co-invents the Soundfield microphone. Gerzon studies at the University of Oxford, and is inspired by Alan Blumlein's landmark