American bass guitarist, who is best known as a member of Double Trouble, a blues rock band led by Stevie Ray Vaughan. Born in Tucson, Arizona, Shannon moved to Dumas, Texas when he was nine, where he originally started as a guitarist, though he started playing bass at the age of 21. He appeared with Johnny Winter at Woodstock in 1969. He later joined Double Trouble in 1981 and became a permanent member of Double Trouble until Vaughan's death in 1990. Shannon and bandmate Chris Layton later formed supergroups such as the Arc Angels and Storyville.