Ernie Ball's latest "String Theory" episode features TOOL bassist Justin Chancellor.

Justin discusses why "playing bass is the ultimate freedom," his early influences and how performing live is the ultimate confluence of emotions.

On enjoying the simplicity of the outdoors and the way it helps inspire his musical expression, Justin says: "Writing music is hard if your head is full of waste. Maybe you have a particular type of sound you want to go for, but if you really want to be original, there's no real recipe for that. For me it's just about letting it come to you...if you can let your head clear out, then almost anything is available."

"String Theory" features a selection of Ernie Ball's most innovative and influential brand ambassadors as they talk about the sonic origins of their tone and playing styles. Recent episodes have featured notable guitar players Butch Walker, Joe Bonamassa and Mike Herrera. Created and produced by Ernie Ball, the series is filmed in the home studios where artists can pick up their guitars and demonstrate skills and tricks they'e learned on their lifelong exploration of the guitar.

It's been ten years since TOOL released its last album, 2006's "10,000 Days". The band has toured a number of times since its release but has apparently gotten serious about making a new record in the past couple of years.