D minor is a minor scale based on D, consisting of the pitches D, E, F, G, A, B♭, and C. In the harmonic minor, the C is raised to C♯. Its key signature has one flat (see below: Scales and keys).

Its relative major is F major, and its parallel major is D major. D minor is one of the two flat-signature keys whose melodic and harmonic scale variations require the addition of a written sharp; the other is G minor.

Some consider it the flattest key that is practical for a guitar to play.^{[citation needed]} Of Domenico Scarlatti's 555 keyboard sonatas, which often borrow mannerisms from guitar music of the period, 151 are in minor keys, and D minor is the most often chosen minor key, with 32 sonatas. Nigel Tufnel, one of the members of the musical spoof megagroup Spinal Tap speaks of "a musical trilogy I'm working on in D minor which is the saddest of all keys, I find. People weep instantly when they hear it, and I don't know why."

J. S. Bach's entire The Art of Fugue is in D minor and, jokingly, so is P. D. Q. Bach's Musical Sacrifice.^{[citation needed]} According to Alfred Einstein, the history of tuning has led D minor to be associated with counterpoint and chromaticism (for example, the chromatic fourth), and cites Mozart's chromatic Fugue in D minor. Mozart's Requiem is also written primarily in D minor. Of the two piano concertos that Mozart wrote in a minor key, one of them is in D minor, No. 20, K. 466. Sibelius's Violin Concerto is in D minor as is Schumann's, although many of the best-known violin concertos are written in D major. The tonality of D minor held special significance for Helene and Alban Berg.

César-Auguste-Jean-Guillaume-Hubert Franck (10 December 1822 – 8 November 1890) was a composer, pianist, organist, and music teacher who worked in Paris during his adult life.

He was born at Liège, in what is now Belgium (though at the time of his birth it was under the Netherlands' control). In that city he gave his first concerts in 1834. He studied privately in Paris from 1835, where his teachers included Anton Reicha. After a brief return to Belgium, and a disastrous reception to an early oratorio Ruth, he moved to Paris, where he married and embarked on a career as teacher and organist. He gained a reputation as a formidable improviser, and travelled widely in France to demonstrate new instruments built by Aristide Cavaillé-Coll.

In 1858 he became organist at Sainte-Clotilde, a position he retained for the rest of his life. He became professor at the Paris Conservatoire in 1872; he took French nationality, a requirement of the appointment. His pupils included Vincent d'Indy, Ernest Chausson, Louis Vierne, Charles Tournemire, Guillaume Lekeu, and Henri Duparc. After acquiring the professorship Franck wrote several pieces that have entered the standard classical repertoire, including symphonic, chamber, and keyboard works.

John Feeley is a classical guitarist and teacher from Ballinasloe, County Galway, Ireland. He has been described by the Washington Post as 'Ireland's leading classical guitarist' and by Michael Dervan in the Irish Times as 'a trailblazer...when it comes to the guitar and guitar-playing in Ireland'.

Feeley is internationally renowned as a performer and teacher and he is regularly found performing and teaching around the world with appearances at such festivals as the Guitar Festival of Ireland, Bath International Guitar Festival, the Dundee International Guitar Festival, and the Wirral International Guitar Festival.

Feeley has won numerous awards including the Special Award for interpretation in the 1984 Mauro Giuliani competition, Italy. He has appeared as a soloist with The American Symphony Orchestra at Carnegie Hall, the RTÉ National Symphony Orchestra, the Ulster Orchestra, the Irish Chamber Orchestra and the Contempo Quartet. He performs regularly in duet with the flautist William Dowdall.

Valentina Lisitsa (Ukrainian: Валентина Лисиця, translit. Valentina Lisitsya,) is a Ukrainian-born classical pianist. Lisitsa resides in North Carolina in the USA. She is among the most frequently viewed pianists on YouTube.

Lisitsa was born in Kiev, Ukraine, in 1973. She started playing the piano at the age of three, performing her first solo recital at the age of four. Despite her early disposition to music, her dream at that point was to become a professional chess player. Lisitsa attended the Lysenko music school for Gifted Children and, later, Kiev Conservatory, where she and her future husband, Alexei Kuznetsoff, studied under Dr. Ludmilla Tsvierko. It was when Lisitsa met Kuznetsoff that she began to take music more seriously. In 1991 they won the first prize in The Murray Dranoff Two Piano Competition. In the same year, they moved to the United States to further their careers as concert pianists. Their New York debut was at the Mostly Mozart Festival at Lincoln Center in 1995.

Lisitsa has performed in various venues around the world, including Carnegie Hall, Avery Fisher Hall, and the Musikverein. Recently, she has been the pianist in recital engagements collaborating with violinist Hilary Hahn. Her recording of the 4 sonatas for violin and piano by composer Charles Ives, made with Hahn, was released in October, 2011. Many of Lisitsa's performances, including Frédéric Chopin's Op. 10 and Op. 25 Etudes and Beethoven's Appassionata Sonata, can be viewed on YouTube.

Emil Grigoryevich Gilels (Ukrainian: Емі́ль Григо́рович Гі́лельс, Russian: Эми́ль Григо́рьевич Ги́лельс, Emiľ Grigoriević Gileľs; October 19, 1916 – October 14, 1985) was a Soviet pianist, widely considered one of the greatest pianists of the 20th century. His last name is sometimes transliterated Hilels.

Gilels was born in Odessa, Russian Empire (now part of Ukraine) to a Jewish family with no direct musical background that nevertheless owned a piano. He began studying the piano at the age of five under Yakov Tkach, who was a student of the French pianists Raoul Pugno and Alexander Villoing Thus, through Tkach, Gilels had a pedagogical genealogy stretching back to Frédéric Chopin, via Pugno, and to Muzio Clementi, via Villoing. Tkach was a stern disciplinarian who emphasized scales and studies. Gilels later credited this strict training for establishing the foundation of his technique.

Gilels made his public debut at the age of 12 in June 1929 with a well-received program of Beethoven, Scarlatti, Chopin, and Schumann. In 1930, Gilels entered the Odessa Conservatory where he was coached by Berta Reingbald, whom Gilels credited as a formative influence. Also in Odessa Conservatory Gilels studied special harmony and polyphony with professor Mykola Vilinsky.