Sunday, November 16, 2014

Records worth keeping

Vinyl records were made obsolete by CDs, but I still find pleasure in them. Much of my interest is based on nostalgia for my youth and for times before I was born and for a more mechanical, less electronic age when people rode trains, wrote with fountain pens, and typed on typewriters, but I also appreciate records for themselves. I like the cover art and liner notes, and I like watching a needle in the groove as a record hypnotically spins round and round. Playing records involves a hard needle pressing into soft vinyl, and they are susceptible to the elements, so they need special care. But first, some background. 

The first long-play records (LPs) were made in 1948. LPs are made from a combination of vinyl acetate and vinyl chloride — polystyrene was often used for 45 rpm 7-inch singles — with carbon black, chemical stabilizers, and lubricants added. A superior quality record contains virgin vinyl, which, some people believe, produces less background noise because it is made from new, not recycled, material.
The grooves are in reality one groove one-third to one-half mile long, changing in depth and width hundreds of times per inch, giving an appearance, when magnified, of a canyon in the Southwest. Grooves gave rise in the jazz community to “in the groove,” “groovin’” and “groovy,” later picked up the rock ’n’ roll generation.
On a monaural record, the needle vibrates from side to side and on stereo from side to side and up and down, producing weak electric waves. A 100 Hz signal requires 200 movements of the stylus per second, and 20,000 Hz requires 40,000 movements per second.
The needle, made of diamond or sapphire, is mounted in the pickup cartridge, and a crystal or magnet in the cartridge produces electric current. A monaural cartridge produces one set of waves and a stereo two sets. The cartridge sends the weak signal to the amplifier, which contains two amplifiers for stereo, where the preamplifier strengthens the waves, which are modified by tone and volume controls. The power amplifier makes the waves strong enough to operate the speakers.
High fidelity sound reproduces sound with the greatest possible faithfulness. Its three requirements: it must reproduce every musical tone that can be heard in a concert hall, it must reproduce loud tones as clearly as soft ones, and it should produce no noise of its own.
The first stereo LPs were made in 1958, creating a demand for stereo hi-fi equipment. Two microphones placed apart made sound more realistic, giving separation and thus dimension to the sound. Speakers must also be placed apart, at least five feet, and pointed in the same direction to reproduce that sound. Four-channel stereo was invented in 1969 but never caught on. If the speakers are placed properly and the balance set to the middle, the sound seems to come from between the speakers.
Because a diamond needle is attacking relatively soft vinyl, the needle distorts the groove while playing. Some audiophiles say that the first few plays permanently distort the groove, and the record should be recorded during the first play. The record should be allowed to recover for at least two hours before being played again.
Records should be handled by the edges and labels, using a non-abrasive material with no lint, such as soft plastic or rubber. They should always be kept in sleeves, with the opening at the top to reduce dust and to prevent the record from falling out of the jacket.
Records should be stored upright because leaning can warp them. Monaural records may be played on stereo equipment, but stereo records should not be played on monaural equipment because monaural needles are wider. I returned several records in high school, thinking they had skips, because I played them on my portable monaural record player. Shrink wrap should be removed because it can shrink more and warp the record.
Dust, lint, dirt, hair, skin oil, food, and tobacco smoke can accumulate in the grooves and can be ground in by the needle. Records should be cleaned before every play with a buffer and a spray cleaner, such as an alcohol-based antistatic spray. If both sides are extra dirty, a record should be more thoroughly cleaned on a plastic or rubber mat before being placed on the turntable to avoid damage to the motor. The cleaning fluid should set for about 20 seconds to lift contaminants, and as much fluid as possible should be removed while cleaning to remove the dirt it has picked up.
The turntable mat should be cleaned periodically, and the needle should be cleaned with a brush or lightly with the buffer. Blowing on a record may remove dust and bigger particles but can add contaminants. The dust cover should always be closed, and groovin’ cats (the feline type) should be discouraged from jumping on it during play.

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