Sites offering music theory, both specific and general, are listed here. Music theory is "a branch of study that includes many different methods for analyzing, classifying, and composing music and the elements of music." (You will find a good writeup of music theory at http://en.wikipedia.org/wiki/Music_theory ) Music Theory is not Musicology. Musicology seeks answers questions for Who, What, Where, When and Why questions. Music Theory seeks answers for How.
http://www.standingstones.com/modeharm.html
A concise explanation of the Gregorian and Renaissance modes and their development in the Common Practice era.
http://www.greenwych.ca/atonal.htm
Claims that atonality is unnatural while tonality is acoustically and historically natural.
http://www.geocities.jp/musikanalyse/eng/text/textE.html
Analysis of full-music 20th Century atonal pieces.
http://www.autotransposer.com/
Transposes all twelve major keys of chord progressions.
http://www.ubieta.com/bimodalism/
A contemporary alternative to atonal styles of composition.
http://www.dolmetsch.com/theoryintro.htm
Offers a musical dictionary, recorder lessons, instrument information and a composers listing.
http://nastechservices.com/Spectrograms.html
Provides a type of spectrogram suitable for understanding the structure of music.
http://www.emusictheory.com/
Java applets designed to help students of music improve their basic music reading skills.
http://www.ericweisstein.com/encyclopedias/music/
A reference resource on music theory, covering in brief a vast array of topics.
http://musictheory.redzeppelin.org/
Summarizes entry-level music theory through advanced topics. Includes beginners' drills.
http://jan.ucc.nau.edu/~tas3/wtc/i17.html
Introduction to the essential concepts of Schenkerian analysis applied to the Ab Major fugue of Bach's Well-Tempered Clavier, Book I
http://www.kunstderfuge.com/theory.htm
Bibliography of fugue analysis research, writings and analysis.
http://www.good-ear.com/
Online ear training site.
http://vladimir_ladma.sweb.cz/english/music/articles/ifsa97.htm
A paper about the unification of Janecek's theory of imaginary tones with the two Risinger's principles of functional relations.
http://www.harmony.org.uk/
By Tom Sutcliffe. Aims to help students of music theory understand the role of chord progressions in musical structures. Site includes animated demos.
http://randscullard.com/CircleOfFifths/
A free music theory tool designed to help musicians interpret chord progressions, easily transpose music to a different key, compose new music, and understand key signatures, scales, and modes.
http://chandrakantha.com/articles/scales.html
A historical look at concepts of Indian scales and modes comparing North and South Indian approaches.
http://www.phys.unsw.edu.au/music/
The science of music. Explanations of how musical instruments work via waves and frequency modulation.
http://www.musictheoryblog.blogspot.com/
A guide to music theory that including chords, scales, music notation and other music theory topics. Has weblog format; includes links as well.
http://www.wmich.edu/mus-history/TheoryHelp/TheoryHelp.html
Intermediate music theory help covering basics through beginning formal analysis and counterpoint.
http://www.angelfire.com/music5/theory/
Online instruction for all musicians beginner or advanced. Covers scales, chordal theory, progression theory, modes and foreign scales.
http://www.ithaca.edu/music/mtsnys/
Provides a forum for the exchange of information and to promote music theory as a scholarly and pedagogical discipline. Site also contains membership and scholarship information as well as open calls for papers.
http://www.musicatschool.co.uk/worksheets.htm
Downloadable worksheets for elementary and middle school students.
http://www.seepatts.com/
Offers visual aid to recognizing musical patterns occurring in melody, harmony and rhythm. Provides online demonstration; requires download.
http://www.musictheory.net/
Includes introductory and intermediate music theory lessons, ear trainers, and books.
http://www.schenkerguide.com/
An introduction to Schenkerian analysis for undergraduate music students. Includes background, working method, glossary and bibliography.
http://www.rhythm-patterns.narod.ru/
Rhythmic exercises with accompanying MIDI files.
http://www.rpsoft2000.com/rps_chordtheory.htm
Explains scales and building chords from them.
http://www.skytopia.com/project/rating.html
Author's overview of how every piece of music, every sound, and every picture can be rated on its own merits outside (as well as inside) human opinion.
http://solomonsmusic.net/
Resources for composers, music theorists, and researchers of music, with sound files, papers and compositions.
http://www.musicarrangers.com/star-theory/
Free preparatory syllabus in music theory and orchestration.
http://www.public.coe.edu/~jcotting/tcmu/
A group within the Acoustical Society of America, that concerns itself with the application of science and technology to the field of music. Contains members, a list of papers, acousticians and links.
http://www.teoria.com/
Includes software, books, exercises, and links.
http://www.pathguy.com/modes.htm
Ideas regarding the "classical modes" described by Plato and Aristotle.
http://www.musictheoryminute.com/
Online music theory tutorials for beginning students.
http://www.tonalcentre.org/
Interactive site for music composers and theorists which explains and demonstrates some of the key concepts of tonality; including chords, scales, cadences, and modulation.
http://www.people.vcu.edu/~bhammel/theory/resources/index.html
Music theory and ear training resources from Virginia Commonwealth University.
http://whatismusic.info/
Provide information on the book by Philip Dorrell which explains a new scientific theory about music: the super-stimulus theory.
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