Dawson transferred to John Muir High School in Pasadena, California, where he met fellow students Vibraphonist Bobby Hutcherson, Bassist Herbie Lewis, and pianist Nat Brown.

With Roger on drums, they formed a quartet called "The Jazz Monitors" and performed at venues in the Los Angeles area until they graduated from John Muir in 1958.

On leave in Amsterdam, Roger ran into Bob Whitlock, the original bassist for the Gerry Mulligan Quartet, who had received a scholarship to the Sorbonne in Paris.

Leaving the service in 1961, Dawson returned to California and the La Jolla/San Diego area, where he went to work for jazz radio station KFMX as a deejay and account executive.

Dawson continued to be active with respect to his jazz roots performing with jazz pianist Ahmad Jamal, Ray Nance, the Gil Evans Orchestra, McCoy Tyner, Roy Haynes, Hannibal Marvin Peterson, Kenny Barron, Billy Harper, Cedar Walton, Herbie Lewis, Freddie Hubbard, Bobby Hutcherson, Sam Rivers, Rashied Ali, Rahsaan Roland Kirk, Hilton Ruiz with George Coleman and toured with jazz saxophonist Archie Shepp in several of Archie's avant-garde bands that featured such players as Jimmy Garrison, Beaver Harris, Dave Burrell, Grachan Moncur III, Walter Davis Jr., Art Taylor, Hilton Ruiz, John Betsch and Santi Debriano; recording with Carla Bley and the Jazz Composers' Orchestra (the epic Escalator over the Hill) with Don Cherry, Charlie Haden, Gato Barbieri, Paul Motian and many others.

Having started his musical training as a post-bop trap player upon arriving in New York in 1965, Dawson combined authentic Afro-Cuban technique, which he had learned from his studies with Patato Valdes, Armando Peraza, Frankie Malabe, Milton Cardona, Tommy Lopez, and others, into the jazz idioms of the 1960s and 1970s, including the Free Jazz Avant Garde movement started in early 1960s Los Angeles by Ornette Coleman.

(John J O'Connor and Robert Palmer, N.Y. Times) In addition to playing historical cuts of vintage Cuban (Antonio Arcano, Benny Moré, Orquesta Aragón, Sonora Matancera, Cachao, Los Papines), and Puerto Rican music and Bomba and Plena rhythms (Ramito, Mon Rivera, and others) while explaining the evolution of modern salsa, he also broke the new albums of New York's emerging roster of Salsa performers.

Dawson created a blend of Latin jazz cuts by artists such as Cal Tjader, Dizzy Gillespie, Chico O’Farrill, Mongo Santamaría, Mark Weinstein (who contributed one of his originals as one of Roger's themes), Dave Valentin, Clare Fischer, Poncho Sanchez, Grover Washington and others mixed with the more "tipico" singer dominated Salsa bands.

He was also instrumental in exposing new and innovative salsa performers and projects such as "Grupo Folklorico Y Experimental Nuevayorquino", Manny Oquendo's Conjunto Libre, the sophisticated work of pianist arranger Jorge Millet, and the original bilingual approach of Angel Canales who could not get airplay on other commercial stations until his exposure on Roger's show broke his albums.

He accompanied the CBS Jazz All Stars, Dexter Gordon, Stan Getz, Woody Shaw, Tony Williams, Willie Bobo, Percy Heath, Hubert Laws, Cedar Walton, Jimmy Heath, Arthur Blythe, Bobby Hutcherson, John McLaughlin, Eric Gale, Weather Report with Wayne Shorter, Joe Zawinul, Jaco Pastorius and Peter Erskine, The Fania All-Stars, with Johnny Pacheco, Héctor Lavoe, Rubén Blades, Pete "El Conde" Rodriguez, Roberto Roena and Papo Lucca, along with Billy Joel, Kris Kristofferson, Rita Coolidge and Stephen Stills.

Roger and fellow conguero Eddie Montalvo, who was with the Fania All-Stars, were invited to join in during an epic conga jam hosted by the Cuban band Irakere led by Chucho Valdés which at that time featured Paquito D'Rivera and Arturo Sandoval before they were eventually able to defect from Cuba and move to the United States.

The trip had to be arranged in secret under very tight security as the right-wing Cuban community in the U.S. had threatened those that would participate in cultural exchanges with the Castro government at that time.