When was stereophonic sound invented

It showed how one needle in a specially cut groove on a record could give out two signals simultaneously resulting in a more stereophonic sound. On the 14th of December the first wax disc was cut in a test recording of stereo sound for the first time at the auditorium of the EMI site in Hayes. Fletcher would lead much of the research on binaural, or what later would be called "stereophonic" sound recording, at Bell Labs.

Keller of Bell Labs with Leopold Stokowski used improved electrical recording equipment in the Academy of Music in Philadelphia to record and transmit monaural and binarual sound. The master disc was gold-coated by vacuum-sputtering. The patent application was not filed until because Bell did not see an immediate commercial application of the method. Transmission was over wire lines from the Academy of Music in Philadelphia and three channels were used with microphones respectively at left, center and right of the orchestra stage and loud speakers in similar positions in Constitution Hall.

With stereo, the sound of some instruments could come from the left speaker, the sound of others from the right, imitating the setup of a concert orchestra.

It also was possible to shift a particular sound from left to right or right to left, creating a sense of movement. Although Audio-Fidelity Records offered a limited edition stereo record for industry use in , consumers needed to wait until for recordings with stereo sound to become widely available for the home.

Stereo was aggressively promoted as the latest technological advancement that brought sophisticated sound reproduction to everyone. After all, adopting stereo meant you needed to buy a new record player, speakers and a stereo amplifier.

Something was needed to show people that this new technology was worth the investment. Stereo demonstration records, in particular, featured attractive, modern graphic design. Honoured at the famous Abbey Road Studios, Alan Dower Blumlein pioneered all kinds of technologies before his untimely death during a top-secret wartime mission.

When you're rocking out to your favourite music, or surround sound has slapped you in the heart of your favourite movie, you know how important stereo sound is. And it's all thanks to Alan Blumlein, the 20th-century pioneer of various technologies who was inspired to invent stereo after a trip to the movies. Blumlein's son Simon and grandson, also named Alan, attended the unveiling of the plaque at Abbey Road Studios in St John's Wood, North London, where Blumlein oversaw one of the earliest stereo recordings.

Alan Dower Blumlein's stereo breakthrough began in when he visited the cinema with his wife Doreen. Frustrated that the sound from a single speaker didn't match up with the actors and action on the screen, he told his wife he had a better idea. That same year, Blumlein filed a patent including a whopping 70 ideas related to stereo, some of which are still in use today.

The first stereo discs were cut in It's a fitting location, then, for Blumlein's contribution to audio technology to be commemorated. Fun fact: EMI Studios was only actually dubbed Abbey Road Studios in -- the building was named after the Beatles album, and not the other way round.