[1][2] In 1944 he began studies as a chemistry major at Tulane University, which he abandoned after completing five semesters of course work.

[3] In 1945, at the age of 18, Matassa opened the J&M Recording Studio at the back of his family's shop on Rampart Street, on the border of the French Quarter in New Orleans.

[1][4] As an engineer and proprietor, Matassa was crucial to the development of the sound of R&B, rock and soul of the 1950s and 1960s, often working with the producers Dave Bartholomew and Allen Toussaint.

In the late 1950s and early 1960s, Matassa also managed the successful white New Orleans rock-and-roll performer Jimmy Clanton.

[5] Matassa is interviewed on screen in the 2005 documentary film Make It Funky!, which presents a history of New Orleans music and its influence on rhythm and blues, rock and roll, funk and jazz.