Dennis Irwin was born on November 28, 1951 in Birmingham, Alabama but grew up in Atlanta and Knoxville. Early in life he discovered music"inspired by older brothers who coached him in jazz early on"and began playing clarinet. As a teenager, his family moved to Houston, where he played in R&B bands playing alto sax and handling lead vocals. He attended North Texas State University studying classical music focusing on his clarinet. Two friends in the program, drummer John Riley and bassist Marc Johnson turned him on to the upright bass at the age of 19: he thus found his true calling and joined the school’s acclaimed Two O’Clock Big Band.
In nearby Dallas, he worked as a sub with pianist Red Garland, who suggested Irwin move to New York. In August of 1974, Irwin headed north to New York when an old friend from high school offered him a place to stay and a job in a Greenwich Village record store. In no time he was gigging with Charles Brackeen, finally landing his first steady gig in trumpeter Ted Curson’s group in 1975. He quickly became the bassist of choice with such vocalists as Jackie Paris, Betty Carter, Annie Ross, Ann Hampton Callaway, Tania Maria and Mose Allison. “It’s challenging to work with a vocalist,” Irwin explains, “because you have to listen for exactly what a singer needs. Sometimes it’s about just getting out of the way, you can’t play too hip, otherwise you draw attention to yourself. But that’s true of playing behind any soloist. Playing the bass is about instinct and calculation.” He looks back upon the years he spent with Allison as “fun, because of Mose’s knack for human and social commentary.”
A number of musicians have served as mentors including bassist Ali Jackson, Sr., best known for the '50s session he co-led with trumpeter Wilbur Hardin featuring John Coltrane. “Listening to Ali taught me so much,” Irwin explains. “He wasn’t as well known as his brother, Oliver ‘Bop’ Jackson, but he really played with tremendous feeling and a strong tie to Africa. Today, people would describe him as something of hippie radical, but those were the times.” Bassist Eddie Jones, known for his work with Count Basie was also a mentor, as were drummers Vernel Fournier, Ben Riley and Leroy Williams. “I’ve been so lucky,” he explains to learn directly from these masters.” A stint with Brazilian pianist Dom Salvador, which included Dennis's first major recording session, jump started his long-term love affair with Brazilian music, fed regularly by Salvador's steady supply of choro charts which Dennis mastered on clarinet, as well as obscure Brazilian recordings.