Rob or ROB may refer to:

Ton Koopman (born 2 October 1944 in Zwolle, Netherlands) is a conductor, organist and harpsichordist.

Koopman had a "classical education" and then studied the organ (with Simon C. Jansen), harpsichord (with Gustav Leonhardt) and musicology in Amsterdam. He specialized in Baroque music and received the Prix d'Excellence for both organ and harpsichord.

In 1979 Koopman founded the Amsterdam Baroque Orchestra and the Amsterdam Baroque Choir in 1992 (now combined as the Amsterdam Baroque Orchestra & Choir). Koopman concentrates on Baroque music, especially that of Bach, and is a leading figure in the authentic performance movement. While a number of early-music conductors have ventured into newer music, Koopman has not. He has said, "I draw the line at Mozart’s death" (1791). One exception is his recording of the Concert Champêtre of Francis Poulenc, written in 1928.

Among Koopman's most ambitious projects was the recording of the complete cycle of all of Bach's cantatas, a project completed in 2005. Soloists for the project were among others Lisa Larsson, Sandrine Piau, Sibylla Rubens, Barbara Schlick, Caroline Stam, Deborah York and Johannette Zomer (soprano), Bogna Bartosz, Michael Chance, Franziska Gottwald, Bernhard Landauer, Elisabeth von Magnus, Annette Markert and Kai Wessel (alto), Paul Agnew, Jörg Dürmüller, James Gilchrist, Christoph Prégardien and Gerd Türk (tenor) and Klaus Mertens (bass). Koopman has received many prizes for his recordings. In 2005 he has commenced Dieterich Buxtehude – Opera Omnia, a project to record the complete works of Dieterich Buxtehude. As of March 2010, eleven volumes have been released. He was elected president of the "International Dieterich Buxtehude Society" in 2004.

Dorothee Mields (born 1971) is a German soprano concert singer of Baroque and contemporary music.

Mields was born in Gelsenkirchen. She studied at the University of the Arts Bremen with Elke Holzmann, Harry van der Kamp and Gabriele Schreckenbach. After graduation she continued studying in Stuttgart with Julia Hamari.

With the Collegium Vocale Gent and Philippe Herreweghe she recorded several Bach cantatas, his Magnificat, Easter Oratorio and Ascension Oratorio. In 2001 she recorded Joseph Schuster's opera Demofoonte on a libretto of Metastasio with La Ciaccona, conducted by Ludger Rémy.

In 2002 she recorded several cantatas for Pentecost of Gottfried Heinrich Stölzel, a prolific contemporary of Bach, conducted by Ludger Rémy. The soloists, including Jan Kobow, also formed the choir. In January 2003 she sang Monteverdi’s Vespro della Beata Vergine on a tour of with the Collegium Vocale Gent. In 2006 performed in Bach's St John Passion with the Tafelmusik Baroque Orchestra in Canada. She sang the soprano part in the recording of Bach's Mass in B minor with Jos van Veldhoven. She recorded songs of John Dowland with the gambist Hille Perl in 2008, and Love Songs of Henry Purcell with the Lautten Compagney Berlin. She was soprano soloist for two concerts of the Bachchor Mainz reviving church cantatas of Wilhelm Friedemann Bach in June 2010, remembering the composers birth in 1710.