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.

I had another idea of getting a traveling medicine wagon with a dropdown side and traveling around England. That might sound crazy to you, but over there it's so rural you can do it. Just drop down the side and play through big battery amps and mixers and it can all be as temporary or as permanent as I want it to be.

The gut-strung guitar, the classical guitar, that is a whole different world on its own. When you think what the guitar can do and what every individual player does with a guitar, everyone has their own identity coming through the guitar.

There's a very old recording maxim that goes, 'Distance makes depth.' I've used that a hell of a lot-whether it's tracking guitars or the whole band. People are used to close-miking amps, but I'd have a mic out around the back, as well, and then balance the two. Also, you shouldn't have to use EQ in the studio if the instruments sound right. You should be able to get the right tones simply with the science of microphone placement.

We went in and recorded exactly where we were at that point in time. I think because of the quality of musicianship of the band has given it the longevity. I thought the music would endure, I didn't think I would ... I always thought I'd be dead by 30, then dead by 40 and on and on. Now I'm 55 so I didn't even die at 50.

There is no way I would play guitar like a tour de force like I did in Led Zeppelin. John Bonham, phenomenal drummer, young man with his technique, but do you think he would ever have the opportunity to play like that in another band? Of course he hadn't.

I don't like being stuck in one situation, day to day.