Sum 41 is a Canadian rock band from Ajax, Ontario. Originally called Kaspir, the band formed in 1996 and currently consists of lead vocalist/rhythm guitarist/keyboardist Deryck "Bizzy D" Whibley, lead guitarist/backup vocalist Dave "Brownsound" Baksh, rhythm and lead guitarist/keyboardist/backup vocalist Tom "Brown Tom" Thacker, bassist/backing vocalist Jason McCaslin and drummer Frank Zummo.