An album which has sold 500,000 copies is certified by the RIAA as “gold.”

5 Reasons to Learn Music Theory
Five good reasons why music theory is a must if you expect to perfect your musical talent.
An album which has sold 500,000 copies is certified by the RIAA as “gold.”
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Five good reasons why music theory is a must if you expect to perfect your musical talent.
The old method of promoting a new act in the music business was for a record company to invest at least $500,000 in studio time with a good producer, the cost of a good video, the advertising budget, and the cost of the first promotional road tour.

A music synthesizer makes sounds by using an electrical circuit as an oscillator to create and vary the frequency of sounds in order to produce different pitches.