There seems to be a resurgence of vinyl long-playing records. Once more they are in the shops, and people are buying turntables to play them. Enthusiasts say that they provide the ‘authentic’ sound that is lost in clinical-sounding CDs or digital downloads.
Does vinyl provide ‘faithful’ reproduction of music? No way José. The first mass-produced gramophones played shellac records at 78 revolutions per minute (RPM). They used a steel needle that was able to reproduce the music without electronic amplification, and were a miracle of purely mechanical engineering. I had one in the 1950s, and first heard the best bits from Wagner’s Götterdämmerung on an old 78 record. The ‘hiss’ from these machines sometimes almost overwhelmed the music – certainly in the quiet bits. The technology improved greatly using diamond or sapphire needles with electronic amplification, on vinyl records rotating at 45 and then 33 RPM. The level of hiss and noise was lower, but it was always there, together with ‘rumble’ from the turntable motor. In the mid 1970s when I started earning money, I wanted decent quality music and built a pair of great cabinets out of chipboard with Wharfedale loudspeakers. I also built an amplifier from a kit – which had to be returned to the manufacturer because I wired it up incorrectly and it blew up – and purchased a reasonably expensive turntable with a diamond stylus. I relished my music and enjoyed, for the first time, hearing both classical and pop in reasonable HiFi. But as the quality of the sound greatly increased it was impossible to ignore the more subtle faults, the ‘pops’ and ‘clicks’: static electricity. There are many problems with vinyl, but the one that drove me quite mad, was that of trying to eliminate static electricity build up. It is virtually impossible, because a rotating dielectric disc with an arm containing metal bits close to it, goes some way to becoming a Whimshurst Machine, an early design of generator for producing very high voltage static electricity. I tried everything: a brush made of carbon fibre (a conductor to conduct away the static electricity), a carbon fibre mat on the turntable platter, even a static gun that was supposed to neutralize the static by spraying static of the opposite polarity. All failed. Then there was the tracking problem which introduced further distortion. When the master disc was cut, the cutting arm did not pivot at one end but tracked the groove, so that the cutting needle was always parallel with the groove. Nearly all turntable decks have a pivoting arm, where the angle to the grooves varies as the record plays. It is possible to get parallel tracking decks but they are expensive – I had one, and the proof of the pudding, an LP that I twice exchanged at the shop because of intense distortion in a crescendo (it was Elgar’s Sea Pictures) played perfectly on my parallel tracking deck. A further problem that can occur, is that a very loud section immediately before or after a quiet section can sufficiently modulate the adjacent groove such that the ghost of the loud bit can be heard during the quiet period. I first heard that in a 45 record of Shakin all Over – Johnny Kidd and the Pirates’ best known hit. Then there is background noise. The stylus pickup needle and coil are very inefficient, so the electrical signal needs a great deal of amplification – lots of gain. High gain means that all the imperfections, mechanical noise and distortion etc. get amplified up to be heard as background noise. And of course, the whole thing is analogue, with the intrinsic difficulty of maintaining linearity at high gain. Admittedly, the overwhelming majority of records that I had a problem with were of classical music, with its far greater dynamic range, but, as noted above, even ‘pop’ music was not immune. So the ‘authentic sound’ that advocates of vinyl claim, consists of surface noise, rumble from the turntable motor, electrical noise from the high gain amplifiers used, tracking distortion and static ‘pops’, not forgetting the regular clicks as the needle encounters a scratch on the disc, and the intrinsic limitations of an analogue, mechanical system to reproduce, with any sort of linearity, the original signal. Give me a CD or digital download any day.
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AuthorWelcome to the Mirli Books blog written by Peter Maggs Archives
December 2024
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