He briefly started his own band in Chicago in 1916 and then played in Bert Kelley’s band and accompanied the singer Blossom Sealy up until 1920 when he left to play with Clint Brush’s Jazz Babies and with Tommy Rodgers.
In 1917 the Original Dixieland Jass Band had a huge hit with the first recorded jazz record “Livery Stable Blues”, but they failed to copyright the song. Yellow Nuņez and Ray Lopez copyrighted the song and published sheet music crediting themselves as the authors of the tune. Nick La Rocca and the band sued for $10,000 and quickly copyrighted the song as “Barnyard Blues”. The plagiarism suit became big news in the papers and at one point La Rocca admitted that he had based the song on Lopez’s “More Power Blues”. The court decided after ten days of testimony that neither the defendants or the plaintiffs were entitled to a copyright and the case was dismissed.
Lopez moved to California in December of 1920 and joined Abe Lyman’s California Orchestra at the Ambassador Hotel in Los Angeles. He was with Lyman until 1927 when Gus Arnheim left the Lyman band and started his own orchestra taking Lopez with him. Lopez stayed with Arnheim until 1929. In the 1930s he formed his own band and continued to gig around until he left the music business in the late 1930s.