The band was founded in 1947; by 1996 (the time of Murad's death), the group was no longer performing. Originally they were named The Harmonica Madcaps and the group consisted of Jerry Murad (chromatic lead harmonica), Bob Hadamik (bass harmonica), Pete Pedersen (chromatic harmonica), and Al Fiore, (chord harmonica). In 1947, the group consisted of Murad, Fiore, Don Les on bass harmonica, and Cappy Lafell on Polyphonia. They eventually (around 1948) became a trio with Murad, Fiore, Les.^{[citation needed]}

In 1947, during the record ban, the group recorded the hit song "Peg O' My Heart" on VitAcoustic records, and it sold more than 2 million copies the first year. It was the first record to use artificial reverb.

Pedersen and Gail Wallace remained contributors to the group throughout its existence, working on arrangements and occasionally recording.^{[citation needed]}

During 1949 when Don Les' father died, the band called upon Johnny Thompson to fill in for Les on bass harmonica for a couple of weeks. Thompson went on to play with them at their residency gig at the Frontier Hotel in Las Vegas in the early 1950s. In the mid-1950s, Les suffered from a detached retina, and Thompson once again took his place until Les was able to return full time later in the decade.^{[citation needed]}. In 1958, Al Fiore suffered his first heart attack and Bob Herndon filled in for him for several months.

In the early 1970s, Don Les left the group and was replaced by Dick Gardner, who stayed with the group more than 20 years. Other members of the group included the following: