Jason Paul McCaslin was born on the 3rd September 1980 in North York, Ontario to father Paul (nicknamed as Porno Paul) and mother Sharon. He has two sisters called Katie and Allison. He was the last member to join the Canadian punk band Sum 41 - he joined in 1999 after Mark Spicoluk (who later went on to play for Avril Lavigne) quit. He attended Exeter High School in Ajax. He picked up his first bass (an El Degas) at 14, when he and a few neighbors decided to start a grunge garage band in high school. This band was unsuccessful and short, and had several horrible names (eg. Wizard, Lizard Tongue and Presse to name a few). Then 41 days into the summer vacation before Grade 12, he joined up with three other aspiring musicians: Deryck "Bizzy D" Whibley, Dave "Brownsound/Hot Chocolate" Baksh, and Steve "Stevo32" Jocz. In 1999 Sum 41 managed to get a record deal from Island Records. Cone likes to remind the band that he is the reason they got signed in the first place, as it happened just a few months after he joined the band.