HOW VINYL WORKS


For most people the word "turntable" brings to mind the scratchy sound of the ancient record players popular in the 1950's. If you think the turntable is nothing but an out-dated and obsolete sound reproduction device, then you are mistaken. Believe it or not, the best quality sound does not come from a CD or even a DVD but from good old fashioned vinyl. Surprised? You shouldn't be. A vinyl record is recorded in analog format. Sound waves through the air, recorded in analog format, are transcribed directly into identical waves on a different medium (vinyl, oxide tape, steel). Because the entire wave is copied, the recorded sound is nearly identical to the sound in the air. CDs and DVDs record in digital format; they take samples of the wave at different times (44,100 times/second for a tape) and convert the general shape of the wave into numbers. As you can see in the graph below, neither CDs of DVDs are able to match the sound wave perfectly.

Comparison of a raw analog audio signal to the CD audio and DVD audio output

Each side of a record contains a single spiral groove. The grooves on a record are exact physical duplicates of the sound waves they are recording. The contours in the groove correspond to the frequency and volume of the reproduced sound wave.

 

 

 

 

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