Jack's musical beginnings happened at Bancroft Jr. High and Fairfax High. At those schools he became friends and musical partners with the late Red Hot Chili Pepper guitarist Hillel Slovak, Eleven singer/guitarist Alain Johannes, bassist Flea and vocalist Anthony Kiedis. 'What Is This' was the first band to emerge in the early 1980's. 'What Is This' played for many years in the LA area which led to the MCA record releases of "Squeezed" and "What Is This". 1983 was the birth year of the Red Hot Chili Peppers. They too played extensively in the LA area (with Jack on drums) and were signed to EMI Records in 1983. Jack continued to play with 'What Is This' until 1986, when he rejoined the Red Hot Chili Peppers and played with them until the summer of 1988. Those years included the release of "The Uplift Mofo Party Plan". In 1990 Jack reunited with Alain Johannes and new musical partner Natasha Shneider to form the band 'Eleven'. Eleven released 3 records in the 1990's with Jack: "Awake In a Dream", "Eleven" and "Thunk". He rejoined Eleven in 2003 for the release of "Howling Book". Also in 1990 Jack recorded and toured for Joe Strummer's album "Earthquake Weather". As a result of that tour he met vocalist Eddie Vedder. Introducing Eddie to the music of Stone Gossard, Jeff Ament and Mike McCready led to the beginnings of Pearl Jam. In the fall of 1994 Jack joined Pearl Jam and played with them through the spring of 1998. His work with Pearl Jam included the releases of "Merkinball", "No Code", "Yield" and the Pearl Jam-Neil Young collaboration "Mirrorball". In 2004 Jack released his first solo record "Attention Dimension". In the years since he has performed on records for 'Spinnerette', 'Die Mannequin' and 'Hole'. His 2nd solo release entitled, "No Heads Are Better Than One" was released August 24, 2010.