I don't want to get too dippy about all this. If you take the view of the scientist and everything is in a state of vibration, then every note is a vibration, which has a certain frequency, and you know that if you put 40 beats into a frequency it's going to be the same note every time. You take that into infrasound and people can be made to be sick, actually killed. Taking it the other way, not to be too depressing, what about euphoria, etc., and what about consciousness being totally... no, I won't go into that one. Time warps.

There is far more sensitivity in acoustic guitar players than could ever be compared to any synthesizer. That's a personal point of view but that's the way I see it. I think that's what it's all about. The drive, the fire, the passion - it all comes out on the guitar.

I feel Aleister Crowley is a misunderstood genius of the 20th century. Because his whole thing was liberation of the person, of the entity, and that restrictions would foul you up, lead to frustration which leads to violence, crime, mental breakdown, depending on what sort of makeup you have underneath. The further this age we're in now gets into technology and alienation, a lot of the points he's made seem to manifest themselves all down the line.

There's a certain standard in classical music that allows the application of the term "genius," but you're treading on thin ice if you start applying it to rock & rollers.

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.

Just because you play bass, doesn't mean you have no presence.

From the classical guitar right through to the furthest electrical experiments and everything in-between, it's amazing what the guitar can actually do. I mean, when one thinks about sounds.