Duple Meter

Duple meter is defined as two beats per measure. These beats within the measure serve as “the framework within which rhythm is established and perceived” according to Grove Music Online. Accents (strong-weak) determine the meter of the piece. Because of this variance in the accents groups, some pieces that have four beats can also be interpreted as duple meter. These accents that determine the meter may be stated explicitly be implied through the music.
Most marches and dances, such as bourees and gavottes, are in duple meter due to the fact that most people have two feet. Also, popular music tends to be in duple or quadruple meter. Within duple meter, there are two more categories: simple duple and compound duple. Most marches that you listen to are good examples of simple duple, such as Pomp and Circumstance. Pieces that are simple duple are usually in 2/2, 2/4, or 4/4. An example of compound double would be “Take Me Out to the Ball Game.” If you listen, it should sound like two large beats subdivided into three smaller parts. Pieces in 6/8 are usually considered to be compound duple.

Tonal Harmony, Fifth Ed., Steven Kostka and Dorothy Payne, McGraw Hill

Tremolo

A tremolo is a “quick and continuous reiteration of a single pitch” (The New Harvard Dictionary of Music, 4th ed., 905). For string instruments, this effect is created by quick up and down strokes of their bows. This effect was first used in the early 17th century and it remains in use today. Also, another type of tremolo is utilized by string players called the slurred tremolo. This is similar to the regular tremolo except the player does not change the direction of the bow, which created a more connected sound. Also, string players can use fingered tremolos, which is created by moving the fingers quickly across the fingerboard. The yet another type of string tremolo is the undulating tremolo. This is created by fingering the same pitch on two strings and then oscillating between them with the bow. The term tremolo was also meant vibrato in the 18th century and it can also mean trill.

For pianists, it is the quick repetition of a single pitch. In Liszt’s La Campanella, it occurs in repeated octaves. This creates an effect much like that of a string tremolo.

For organists, tremolo is used in the context of a tremulant stop. A tremulant stop affects the wind supply to the organs to cause fluctuations in the pressures to the wind-chests, which produces and effect much like a vibrato (905).

For singers, a tremolo usually refers to the excessive amount of vibrato. It was widely used in the 17th century, but is rarely used now. In fact, it was disparagingly called a goat’s trill in the 18th century (905).

Tonic

In Western music, the tonic is the main note of the scale and it is the pitch after which the key is named. For example, in C major or minor, C is both they name of the key and the tonic. Also, tonic can be defined as the first scale degree in a particular key. For example, Ab is the first degree in the key of Ab major or ab minor, followed by the supertonic which in this case would be Bb. Also, the word tonic can be used when talking about a tonic triad. A tonic triad is rooted in the first-scale degree and is usually the final chord in a piece of music according to Grove Music Online. The tonic is generally thought of as the root for the rest of the melody and harmony in Western music. In the 20th century, atonal music has gained a following with music that does not feel that it has a particular tonic pitch as other tonal music does.

Piano Trio

A piano trio is a chamber ensemble consisting of a piano and two other instruments, most commonly violin and cello. Other combinations are piano with flute and cello, clarinet and viola, clarinet and cello, and violin and horn. Throughout the 18th century, trios experienced a shift in the importance of the strings to the piano.
Some of the most well-known trios are the Beaux Arts Trio and the trio consisting of Emanuel Ax, Young Uck Kim, and Yo-Yo Ma according to guide.info. Some well-known composers of piano trio music are Haydn, Mozart, Beethoven, Hummel, Schubert, Schumann, Brahms, Tchaikovsky, Shostakovich and Dvorak. The form of piano trios is often in the overall form of a sonata. Sonatas usually consists of four movements: a fast movement in sonata form , a slower movement, a minuet/trio or a scherzo, and finally a quick movement often in rondo form.

Piano quintet

A piano quintet is a chamber ensemble consisting of a piano and four other instruments. After about 1800, these other instruments have tended to be a string quartet. The piano quintet trend grew out of accompanied piano sonatas, divertimentos, and concertos in the second half of the 18th century.
Although there was usually a distinction between the repertoire of piano quintets and concertos, some quintets often resemble concertos in the predominant piano scoring and in their instrumentation throughout the late 18th century. J.C. Bach called for flute and oboe in one work, oboe and viola da gamba in another. Many used strings, but some such as Mozart and Beethoven used only winds. Also, the majority of the composers during the 1770s to 80s were accomplished pianists and scored heavily for piano.
By the middle of the 19th century, works by Schumann, Spohr and Berwald wrote for the conventional instrumentation and extended passages for piano were more rare. These 19th century composers include Brahms, Rimsky-Korsakov, Dvorak, Anton Rubinstein, Saint-Saens, Sibelius, and Granados.

Piano quartet

Piano quartet: A piano quartet is a small ensemble whose instrumentation is piano and three other instruments, usually violin, viola, and cello according to New Grove Online. The trend grew out of the accompanied piano concertos and divertimentos of the 1750s to 80s that were scored for piano, two violins, and cello.
The scoring and instrumentation has gone through a great deal of change as piano quartets started to become more popular. After about 1780 a shift towards violin, viola, and cello as the popular instrumentation for piano quartets. After about 1800, wind instruments also started to become a more popular in the piano quartet setting.
During the 1780s and 90s, the quartet scene grew immensely. Mozart was the most known at this time, but Haydn and Beethoven were also well known composers. Also during this time, the all of the instruments started to play an equal role in the quartet. For example, Mendelssohn and Brahms both deemphasized the piano in their quartets.
Composers have written for more varied groups in the 20th century. Anton Webern wrote a quartet for piano, violin, clarinet, and tenor sax and Olivier Messiaen wrote for piano, violin, cello and clarinet.

Dissonance

Dissonance: Dissonance is a sounding together of two or more notes perceived as having “roughness” or “tonal tension” according to the Grove Music Online. Dissonance can also be defined as those intervals that are generally considered “secondary and unstable” (The Harvard Dictionary of Music 4th ed., 209). Those that are excluded from the dissonance category are referred to as consonant. For example, suspensions are usually dissonant notes that resolve to form a more consonant interval, such as 7-6 suspensions. Perhaps the most applicable display of dissonance for all of us maybe that of the dissonance game.
As time has evolved, so has the acceptance, and therefore the classification, of dissonant intervals. The Babylonians considered everything to be dissonant other than the octave, fifth, octave-plus-fifth, fourth, and the double octave. By 1400, the list of dissonant intervals included seconds, fourths, sevenths, augmented/diminished intervals, and their compounds. Only 300 years later, theorist Schoenberg rejected any absolute distinction between consonance and dissonance.
The use of triads created the need to classify these chords also within the context of dissonance and consonance. Theorists concluded that diminished triads in root position and major, minor, and diminished triads in second inversion are dissonant.
For thousands of years, theorists have attempted to master the “correct” categorization of dissonance and consonance. Pythagoras believed that dissonances were made by the ratios of the string lengths. Others believe that it is defined by the properties of the overtone series and yet others believe it should simply be left for the audience to decide (209-210). To me, it obvious that society’s reaction to dissonance is constantly changing (Ravel and Debussy were the norm at one time and now Eminem rules…and that is just 100 years ago) and that no equation or “general feeling” regarding music that will ever completely catagorize it.

Am I seeing double...no, it is just a Double Stop

Double Stop: Double stop is the playing of two pitches at the same time to create the effect that the two notes are being played at the same time. This stopping, a.k.a. fingering, of the notes allows the two notes to sound simultaneously despite the fact that the curve of the instrument forces the performer to play the notes in succession. To correctly create this effect, the performer must play the lowest string first before moving the bow to the other strings. Also, this can be performed with more than two notes, then called multiple stops. This double stopping technique was described in Ganassi’s Regola rubetina (The New Harvard Dictionary of Music, 253), written in 1532 as the first important tutor for the viola da gamba according to Patricie Connelly.
Sixteenth and seventeenth century composers Marini and Biber use double stops extensively in their works, however the most celebrated works with double stops are the violin and cello works by Bach written in the 18th century. In 19th century music, the technique is also used frequently by Paganini.