[C 1] He started being solo violoncello at the Concerts Hasselmans[2] then, in 1909, succeeded to the famous cellist André Hekking as cello professor in the conservatory of Bordeaux, position that he kept until 1950.
[6] He gave quite a number of concerts, most in Bordeaux[7] and around (e.g. in Arcachon[A 2] from 1910 to 1926) including in northern Spain, but also a few in Paris.
[9] He was close to, or played with, other composers like Halina Krzyżanowska,[10] Maurice Ravel,[11] Jean Roger-Ducasse,[12] Guy Ropartz,[13] Albert Roussel,[14] Florent Schmitt[15] or Charles Tournemire[16] and performers like Lucien Capet,[9] Claire Croiza,[13] Paule Dencausse,[17] Paul Loyonnet,[18] Gaston Poulet[19] or Blanche Selva.
[citation needed] He was the author of a transcription of seven Bach Inventions called "Sept pièces pour deux violoncelles concertants ou pour violon et violoncelle – sans accompagnement de piano", still edited today.
[22] Main founder of the Society of Chamber Music of Bordeaux,[23] he remained, as well as his wife Marie-Valentine, Technical Adviser for a long time.
[B 3] Louis Rosoor has been an outstanding actor in the musical activity of Bordeaux in the first half of the 20th century.