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Established 1998

Vinyl Record Album Frequently Asked Questions (FAQ)

1. What is mastering mean for CD vs. vinyl?
2. How does mastering differ for CD vs. vinyl?
3. What should I know about gramophone records?
4. What is the RIAA Equalization Curve?
5. What is Direct Metal Mastering?
6. What is the meaning of some audio term?
7. What are your rates?

A gramophone record (also phonograph record, simply record, album or LP) is an analogue sound recording medium consisting of a flat disc with an inscribed modulated spiral groove usually starting near the periphery and ending near the centre of the disc. [There are exceptions to this rule: one Monty Pythom record from the 1970's played from the centre out to the edge.]

Gramophone records were the primary technology used for personal music reproduction for most of the 20th century. Invented in 1888, they replaced the phonograph cylinder in the 1900's, and although they were supplanted in popularity in the late 1980's by digital media, they continue to be manufactured and sold today.

Everything and more than you ever wanted to know about the history of the "Gramophone Record" can be found here at Answers.com.

Since the 1960's, everything recorded to vinyl when the lathe master is cut is run through an analog process which produces frequencies that fit what the Recording Industry Association of America's " RIAA Equalization Curve", introduced as a standard in 1954, which is still used today in recording to vinyl and in phono pre-amps for playing back records.

To quote from the Wikipedia:

RIAA equalization is a form of preemphasis on recording, and deemphasis on playback. A record is cut with the low frequencies reduced and the high frequencies boosted, and on playback the opposite occurs. The result is a flat frequency response, but with noise such as hiss and clicks arising from the surface of the medium itself much attenuated. The other main benefit of the system is that low frequencies, which would otherwise cause the cutter to make large excursions when cutting a groove, are much reduced, so grooves are smaller and more can be fitted in a given surface area, yielding longer playback times. This also has the benefit of eliminating physical stresses on the playback stylus which might otherwise be hard to cope with, or cause unpleasant distortion.

Due to the analog circuitry used in the transformation, and the reduction and boosting of audio frequencies that occurs at the high and low ends respectively, the results are not exactly as they were on the original recording, because this analog compression is "lossy", meaning a certain amount of information is lost in order to achieve the reduction and expansion in those frequencies.

You can read the formula, and see a simple graph of the playback frequenices, which you will note is not linear ("straight") as well as a table of how ranges of frequences are boosted or reduced by decibel here.

You can also read an excellent article on the history of equalization and the RIAA curve.

There's also a detailed page on circuitry to equalize audio based on the RIAA curve specifications.

In record pressing terminology, Direct Metal Mastering involves cutting a groove directly into copper metal. Stampers are plated directly from the DMM Copper Master, eliminating two of the three plating steps required for lacquers. DMM Mastering produces records with lower distortion, superior high frequency response, longer program times and quieter surfaces than mastering on lacquers. This creates a "brighter", more pristine sound.