According to its website,
The Chamber Orchestra Of London is London’s finest commercial session orchestra, drawing its members from principals of all the major London orchestras, international soloists, chamber and session musicians.
The orchestra has collaborated with artists like George Martin, and Madonna. They have performed many film and television scores including Harry Potter and the Order of the Phoenix, and Harry Potter and the Half Blood Prince.
The most popular song by The Chamber Orchestra of London's is Mr. Turner’s Waltz
The Chamber Orchestra of London's first song Mr. Turner’s Waltz released on Fri Feb 14 2020.