James Hetfield wasn't ''100 per cent on with'' Metallica's music from 1996 to 1997.

The heavy metal group's frontman - who co-founded the band with drummer Lars Ulrich in 1981 - has admitted he wasn't completely convinced by two of their albums, 1996's 'Load' and 1997's 'Reload', but went along with them as a ''compromise'' to the other members.

He said: ''There always has to be some kind of compromise - especially when you've got four guys in a band. ''You've got two guys that are really driving the thing - Lars and myself - and when we don't agree, there has to be a compromise.

''But as far as doing something that doesn't feel right, I'm sure there's been a few times that it's happened - the 'Load' and 'Reload' era, for me, was one of those; the way that was looking, I wasn't 100 percent on with it, but I would say that that was a compromise.

''I said, 'I'm going with Lars's and Kirk's vision on this. You guys are extremely passionate about this, so I'll jump on board, because if the four of us are into it, it's going to be better.' ''

On reflection, the 54-year-old singer doesn't think the two records were ''as good'' as he ''was hoping'' they would be, but doesn't regret being a part of them.

He said: ''So I did my best with it, and it didn't pan out as good as I was hoping, but, again, there's no regrets, because at the time it felt like the right thing to do.

''So, even thinking that I need to compromise a little bit for the integrity of the band to go forward, I'd do that.''

Despite selling more than 120 albums worldwide since they formed, the 'Master of Puppets' hitmaker insists the group - also made up of Kirk Hammett and Robert Trujillo - still have something ''to prove''.

Speaking to Clash magazine, James added: ''We're still wanting to prove something to ourselves, I guess. I don't know what it is, but the next one's going to be better. As a lyricist and a guitar player, I'm looking for the ultimate riff, the ultimate guitar sound, the ultimate lyric, the perfect rhyme - all of that stuff still, and it's still a quest.''