If you wanted to chart new territories and head off over the horizon, you had to make sure you weren't overly influenced by what others were doing ... so it didn't matter what other bands were doing ... we did what we were doing.

Many people think of me as just a riff guitarist, but I think of myself in broader terms. As a musician I think my greatest achievement has been to create unexpected melodies and harmonies within a rock and roll framework. And as a producer I would like to be remembered as someone who was able to sustain a band of unquestionable individual talent, and push it to the forefront during its working career. I think I really captured the best of our output, growth, change and maturity on tape - the multifaceted gem that is Led Zeppelin.

I don't deal in technique. I deal in emotions.

There's so many different styles and facets of the 360-degree musical sphere to listen to. From tribal to classical music, it's all there. If the bottom was to sag out of that, for God's sake, help us all.

We kept moving forward and didn't try to recreate the past .. the approach to each album was radically different every time. Many bands would have some success and, because they were locked into having a single - something we didn't have to worry about - they had to make sure there was something similar on the next album ... that was never the idea with Led Zeppelin .. the goal was to keep that spark of spontaneity at all times.

I always thought the good thing about the guitar was that they didn't teach it in school.

There's so much that can be done on the guitar. And that's what is so good about the guitar - everyone can really enjoy themselves on it and have a good time, which is what it's all about.