So Robert wasn’t the first choice. But he became the best singer of them all in that style you once called “the primeval wail”, didn’t he?
Yes. Absolutely. And he was a damn fine lyricist as well. I was writing lyrics in the early days and encouraging him to write more because I knew he was going to be a much better lyricist than I ever was. Then it got to the point where he was writing all the lyrics, and I was very content with that because it allowed me to concentrate totally on the music.

I talked to him the other day and he’s very dissatisfied with his singing on the first couple of albums. Why do you think he’s so self-critical?
I know he’s not happy with the ad-libs on Led Zeppelin I, but I think he should be really pleased with his vocal approach. He was performing in a very inspired way, like everyone else in the band. What he did was really fitting in terms of where we were going. It was an essential element. And millions would agree with me and not with him on how great his singing was on those first couple of records.

Was it a conscious decision to move in a more acoustic direction on Led Zeppelin III?
There were a lot of bands at the time who had a hit and a format and they stuck to that. What we were doing was different. When we went in the studio, it was a summing up of where we were at that point in time. So there was no way the third album was going to be like the first. Then there was no way the fourth album was going to be like the third. If there was a Zeppelin philosophy, it was always: “Ever onwards. Let’s see what we can do next.”

A lot of people would say Physical Graffiti in 1975 was a kind of high-water mark for Zeppelin.
I’d probably agree with that.

Were the later records more difficult to make, with so many other things going on around the band?
Up to Graffiti, we hadn’t experienced any of the tragedies that happened. First of all there was Robert’s accident. The album that was done around that period was Presence. That was recorded in just over three weeks from beginning to end, and the urgency of it is there if you listen. But it’s not an easy album for a lot of people to access. And because a lot of people found that a difficult album to listen to, I think the writing took another shift on the next album, which was In Through The Out Door and was recorded in Stockholm, again over a quite short period of time. It wasn’t rushed. It was just that we worked so very fast. And again, it was a summing up of where we were at that moment in time. When Robert lost his son, that was another tragedy and it affected him deeply.

Then after the various traumas within the band and the punk onslaught on the so-called dinosaur bands, Knebworth was an amazing comeback, wasn’t it?
Look at the DVD and you can see we were really thrilled to be playing again. We were about to embark on the American tour and the game plan was definitely for another album, which I think would have been different again.

I was going to ask you that. Just when you seemed to have survived all of the traumas and come out the other side, John Bonham died. Where do you think Led Zeppelin might have gone if that hadn’t happened?
For my part, I’d already discussed the next album with him. We said we were going to resort to some really intense riffing. I don’t want necessarily to call it heavy, but you know what I mean by that. That’s the way I figured the next album should be, because the music had started to lighten up on In Through The Out Door and I wanted to get back to that sort of urgent intensity we managed to evoke. That was the discussion I had with Bonzo, anyway. But who knows? The potential was definitely still there.

Do you think it was inevitable that you and Robert would get back together again in the ’90s?
No, not necessarily. In fact, it wasn’t inevitable at all. But Unledded was great fun to do. We took it around the world again. The seductive playing of the Egyptians – thousands of people had never heard anything like that before, so it was great to represent that sort of musical tapestry. We even had Nigel Eaton playing hurdy-gurdy onstage with us. The album was like one dress rehearsal and then – “Let’s do it.” That was great, but on tour it got even better, like you always do on the road when things start to fall into place and mutate.

Did you feel that if you were going to do old Zeppelin material you had to represent the songs in a new way to make it meaningful, and not come over as some kind of nostalgia act?
But we never did the songs in the same way. Never. In Zeppelin we may have had the framework, but it would change all the time. That’s the way we played and I’d always played like that in all the bands I’d ever been with from day one. There was always the capability to improvise. You go onstage and you have a benchmark. But then you say, “Right, let’s see what’s going to happen tonight.” That not only keeps you on your toes, but it gives a sharp edge to the music as well.

What’s next? Is there going to be a new record?
Yes, there is. My main intention this year is to get up to speed. The way to look at it is that I took a year out. I had some things to sort out and that’s done and now it’s time to get back on a serious roll this year. And hopefully there will be some music. What I need to be doing is trying to make a new musical statement. I had some great fun playing with The Black Crowes. But we were doing a lot of Zeppelin material on that tour. Then I was busy doing the DVD and the How The West Was Won live album. That was great fun as well. But now’s the time to do something that makes people say, “I didn’t think you’d do that, but I can see why you’ve done it.” We’ll see what we come up with. I’m not retired yet, if that’s what you’re thinking.

One suggestion I read last year was that you might make a collaborative album with different singers and songwriters, as Carlos Santana has done recently.
That’s not what I’ve got in mind at the moment, although other people did make some overtures of that kind. There are so many avenues I could take at this point. Or maybe they’re footpaths. It’s just a question of which one to commit to, because when you get involved in a project it’s a time-consuming thing. Let’s put it this way: I’ve got a line drawing. I just haven’t filled the colour in yet.

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