Overview
A copyist is a person that makes duplications of the same thing. The modern use of the term is mainly confined to music copyists, who are employed by the music industry to produce neat copies from a composer or arranger's manuscript. However, the term is sometimes used for artists who make copies of other artists' paintings.
Music copyists
Until the 1990s, most copyists worked by hand to write out scores and individual instrumental parts neatly, using a calligraphy pen, staff paper, and often a ruler. Producing parts for an entire orchestra from a full score was a huge task. In the 1990s, copyists began using scorewriters – computer programs which are the music notation equivalent of a word processor. (Such programs include Sibelius, Finale, MuseScore, LilyPond, and many others). Scorewriters allow the composer or songwriter to enter the melodies, rhythms and lyrics to their compositions into the computer using a computer mouse or keyboard or by playing the notes on a MIDI-equipped instrument. Once a composition is fully entered into a scorewriting program, the computer can be instructed to print out the parts for all of the different instruments.
Both handwritten and computer-based copying require significant understanding of musical notation, music theory, the musical styles and conventions of different styles of music (e.g., regarding appropriate ornamentation, harmony rules pertaining to accidentals, etc.), and strong attention to detail and past conventions. Johann Sebastian Bach's second wife, Anna Magdalena, regularly copied compositions by her husband, including some entries into the Notebook for Anna Magdalena Bach, e.g. "Bist du bei mir", BWV 508. Ludwig van Beethoven had a contentious relationship with his copyists, who often made mistakes that remained uncorrected until the advent of Urtext editions; some musicologists have devoted a lot of effort to identifying Beethoven's copyists.
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