Musical theory is vital knowledge for anyone wishing to compose music involving more than half a dozen instruments. It is recommended knowledge for anyone wishing to arrange music for more than half a dozen instruments. Anyone who writes music for more than about half a dozen instruments without knowledge of musical theory is inevitably either writing an arrangement of a simpler piece or composing modern music.

Serving suggestion: Musical theory best served with at least 2 years experience with actual musical instrument.
John spent two and a half years at the Vienna Conservatorium of Music learning musical theory.
by Bob Hu January 05, 2004
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Basically, a way of analyzing music.

Specifically, music theory is made up of laws, rules, labels and other insights regarding Western music (particularly its harmonic tendencies), pioneered by a man named Rameau.

Music came first, theory came after.
In Music Theory, Roman numeral labels are given to chords in relation to a melodic key center. IV-V-I is the strongest cadence in Western harmony.
by stadam anley January 27, 2009
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Essentially, the alphabet of music. It is important to learn theory so that when you decide to break the rules, you are doing it out of wisdom, and not out of ignorance. See: Miles Davis
Music theory teaches you important rudimentary skills necessary to be successful as a professional musician.
by rtcp September 27, 2006
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1. The study of musical structure and aesthetics, concerning chord structures, musical intervals, rythms, meters, scales, etc.

2. Something that the majority of modern music artists lack knowlege of
Most recording artists seem to think that fashionable clothes and expensive studio recordings, rather than solid music theory, can make their music good.
by Juan September 28, 2003
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1. A subject that 75% of "musicians" out there have never touched.
2. An excuse the ignorant make to put down artists that try to push the boundaries of contemporary music. All the while these same ignoramuses believe poor technique and slop equate with good music just because everybody else thinks so. These people also have never bothered to actually listen to the music they loathe so much.
3. A set of (flexible) rules that dictate the manner in which music functions.
In most introductory music theory courses, students learn about the intervallic structure of the major scale and how it is harmonized.
by Brian February 26, 2004
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A class that explains the structure of music. You'll learn the difference between an A-sharp and a B-flat. Later you get into the rules of writing counterpoints and four-part harmonies, which are useless unless you write classical music, but are still good to know.
Music theory is the first music class I had to take in which I actually had to THINK.
by Mike the Ekim March 25, 2006
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The principles/guidlines of classical, real music. Modern musicians tend to neglect music theory or have little knowledge of it. However, most knowledgeable musicians have a basic idea of theory. (Steve Vai and Yngwie Malmsteen to cite two)
Person 1: "Hey, play me a Em, FM, and GM in common time so I can put together a solo using the Em scale."
Person 2: "Whats common time?"
Person 1: "Oh great, I'm jamming with a moron."

You look like an asshole when you don't know music theory.
by Markus5273 October 03, 2005
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