Characteristics of 20th Century music:
During the 20th century, tone colour has become a more important element of music then it was ever before. It has a major role: creating variety, continuity and mood.
In modern music, noise-like and percussive sounds are often used and instruments are often played at the very top or the very bottom of their register. Uncommon playing techniques have become normal. Flutter-tongueing and other special techniques are also employed to make 20th century music distinctive.
Percussion instruments rose in importance in the 20th century. 20th century composers are interested in unusual rhythms. Celestas, wood block and xylophone are a few. Composers sometimes made use of noise makers such as sirens and typewriters to add colour to the music. Piano is no longer used to provide the lyrical and singing tone of the Romantic. They are now used for persussive or Jazz effect.
Modern orchestral and chamber works often sound transparent. Individual tone colours are heard clearly. To bring the individuality of the different melodic lines that are played simultaneously. The composer will also assign diffrent parts to instruments of diffrent timbre in order to bring out their colours.
In the 20th century, instruments are not place into strict groups. Usage of instruments are all up to the composer's whim. It may be as little as 1 person and it may be as much as one thousand.
Consonance are no longer in use in the 20th century. Dissonance became very important an infact most of the piece is made up of dissonant chords. in the 20th century one would not get the final fufillment one expects. On the whole, 20th century music sound fantasy like, distant and mystifying.
Chords are never as fundemental as it is in previous centuries. Polychords are created by placing one traditional chord over another.
Fourth chords are also employed they are chords made up of notes that are a fourth apart instead of the usual three.
Tone cluster is also created. Chords are made up of notes who are semitones apart it can be produced by striking on the piano a group of adjacent keys.
The rhythmic vocabulary of the 20th century was exoanded with increased emphasis on irregularity and unpredictability. Meters can change every bar or so having an effect of imbalance.
We may count:1-2-3-4-5, 1-2-3, 1-2-3-4-5, 1-2-3 and so on.
Polyrhythm may also be employed. It is similar to Brahm's cross rhythms with one voice playing 1-2, 1-2 and the other voice playing 1-2-3, 1-2-3.
Melody is very elusive in the 20th century. Composers advocated atonality ( non-melodic sort of composition ) and melodies that can be sung or hummed is very few.