First the history
It took a genius like Edison to work out that grooves could store information to reproduce sound. He made this work but then his eyesight could have been failing as he moved on to inventing the incandescent light bulb
Next the grooves were made in wax, this developed by Alexander Graeme Bell among others. The first commercially available pre-recorded music was on wax cylinder from the 1880s with disc records taking over from the 1900s single sided and double sided from the 1910s.
These were originally made from shellac and played at 78rpm with thorn or steel pick-ups until polyvinyl chloride records started from the 1940s. In the quest to increase playing times vinyl became microgrooves and smaller stylii came in. The introduction of different equalisations from different labels was standardised in the 50s to the RIAA curve still used today. This is why you need a phono stage or a special amplifier input to bring the record's output back to the correct frequency response. As you are dealing with a tiny voltage from the cartridge it is so important to get this right, resulting in phono stages costing anything from under £ 100 to many thousands.
The late 50s brought us stereo and new recording techniques, the 60s brought us better more accurate pressing and then the vinyl disaster called The Beatles happened.
Actually it wasn't just the Beatles, it was the fact that the new volumes involved and money to be made meant that the music business grew up into a business about business rather than being about music. If you can save a shilling by making a record sound worse then over a million sales that 's progress! The best engineers who came out of war after designing radar then worked at EMI and Decca to make great recordings with the aim of bringing pleasure and progress to the public. Their pivotal position was usurped by the owners, managers and agents who worked out that by ripping off the young vulnerable artists and the punters who paid for the product they would become very very wealthy.
I promise to move on to turntables in the next instalment! Here is a picture to whet your appetite
