A Garland for Dr. K. is a set of eleven short compositions created in 1969 for the celebration of the eightieth birthday of Dr Alfred Kalmus, the director of the London branch of Universal Edition. It is also the title of an album containing these eleven pieces of music, recorded in 1976.

The term string quartet is a type of musical composition or a group of four people who play the quartets. Many composers from the mid-18th century onwards wrote string quartets. The associated musical ensemble consists of two violinists, a violist, and a cellist. The string quartet was developed into its present form by the Austrian composer Joseph Haydn, whose works in the 1750s established the ensemble as a group of four more-or-less equal partners. Since that time, the string quartet has been considered a prestigious form; writing for four instruments with broadly similar characteristics both constrains and tests a composer. String quartet composition flourished in the Classical era, and Mozart, Beethoven and Schubert each wrote a number of them. Many Romantic and early-twentieth-century composers composed string quartets, including Mendelssohn, Schumann, Brahms, Dvořák, Janáček, and Debussy. There was a slight lull in string quartet composition later in the 19th century, but it received a resurgence in the 20th century, with the Second Viennese School, Bartók, Shostakovich, Babbitt, and Carter producing highly regarded examples of the genre, and it remains an important and refined musical form. The standard structure for a string quartet as established in the Classical era is four movements, with the first movement in sonata form, allegro, in the tonic key; a slow movement in a related key and a minuet and trio follow; and the fourth movement is often in rondo form or sonata rondo form, in the tonic key. Some string quartet ensembles play together for many years and become established and promoted as an entity in a manner similar to an instrumental soloist or an orchestra.

In Freundschaft (In friendship) is a composition by Karlheinz Stockhausen, number 46 in his catalogue of works. It is a serial composition for a solo instrument, first for clarinet, and later arranged by the composer for many other instruments, often in friendship to specific performers. In Freundschaft was first conceived in 1977 as a birthday present for clarinetist Suzanne Stephens, and was first performed at her birthday party in Aix-en-Provence on 28 July that year in a version for the flute. It was later reprised on other instruments as the composer adapted it to nearly every standard orchestral instrument at the request of performers. The work is an example of formula composition, with a basic motif first being presented and then varied in two contrasting, cyclical layers; interrupted by cadenzas. The work has been recorded multiple times, including under the supervision of its composer.

Kontakte (German: [kɔnˈtaktə] , 'contacts') is an electronic music work by Karlheinz Stockhausen, realized in 1958–60 at the Westdeutscher Rundfunk (WDR) electronic-music studio in Cologne with the assistance of Gottfried Michael Koenig. The score is Nr. 12 in the composer's catalogue of works, and is dedicated to Otto Tomek.

Kreuzspiel (Crossplay) is a composition by Karlheinz Stockhausen written for oboe, bass clarinet, piano and four percussionists in 1951 (it was later revised for just three percussionists, along with other changes). It is assigned the number 1/7 in the composer's catalogue of works.

Karlheinz Stockhausen (German: [kaʁlˈhaɪnts ˈʃtɔkhaʊzn̩] ; 22 August 1928 – 5 December 2007) was a German composer, widely acknowledged by critics as one of the most important but also controversial composers of the 20th and early 21st centuries. He is known for his groundbreaking work in electronic music, having been called the "father of electronic music", for introducing controlled chance (aleatory techniques) into serial composition, and for musical spatialization. Stockhausen was educated at the Hochschule für Musik Köln and the University of Cologne, later studying with Olivier Messiaen in Paris and with Werner Meyer-Eppler at the University of Bonn. As one of the leading figures of the Darmstadt School, his compositions and theories were and remain widely influential, not only on composers of art music, but also on jazz and popular music. His works, composed over a period of nearly sixty years, eschew traditional forms. In addition to electronic music – both with and without live performers – they range from miniatures for musical boxes through works for solo instruments, songs, chamber music, choral and orchestral music, to a cycle of seven full-length operas. His theoretical and other writings comprise ten large volumes. He received numerous prizes and distinctions for his compositions, recordings, and for the scores produced by his publishing company. His notable compositions include the series of nineteen Klavierstücke (Piano Pieces), Kontra-Punkte for ten instruments, the electronic/musique-concrète Gesang der Jünglinge, Gruppen for three orchestras, the percussion solo Zyklus, Kontakte, the cantata Momente, the live-electronic Mikrophonie I, Hymnen, Stimmung for six vocalists, Aus den sieben Tagen, Mantra for two pianos and electronics, Tierkreis, Inori for soloists and orchestra, and the gigantic opera cycle Licht. He died at the age of 79, on 5 December 2007 at his home in Kürten, Germany.

Solo for a melody instrument with feedback is a work for a soloist with live electronics (four technician assistants) composed in 1965–66 by Karlheinz Stockhausen. It is Nr. 19 in his catalogue of works. Performance duration can vary from 10½ to 19 minutes.

Spiral (Spiral [adj.], Spirally), for a soloist with a shortwave receiver, is a composition by Karlheinz Stockhausen, written in 1968. It is Number 27 in the catalogue of the composer's works.

Tierkreis (1974–75) is a musical composition by the German composer Karlheinz Stockhausen. The title is the German word for Zodiac, and the composition consists of twelve melodies, each representing one sign of the zodiac.

Zyklus für einen Schlagzeuger (English: Cycle for a Percussionist) is a composition by Karlheinz Stockhausen, assigned Number 9 in the composer's catalog of works. It was composed in 1959 at the request of Wolfgang Steinecke as a test piece for a percussion competition at the Darmstadt Summer Courses, where it was premièred on 25 August 1959 by Christoph Caskel. It quickly became the most frequently played solo percussion work, and "inspired a wave of writing for percussion".

Zyklus für einen Schlagzeuger (English: Cycle for a Percussionist) is a composition by Karlheinz Stockhausen, assigned Number 9 in the composer's catalog of works. It was composed in 1959 at the request of Wolfgang Steinecke as a test piece for a percussion competition at the Darmstadt Summer Courses, where it was premièred on 25 August 1959 by Christoph Caskel. It quickly became the most frequently played solo percussion work, and "inspired a wave of writing for percussion".