Coldplay have been approaching new songs "as though they are a metal band".
The group - comprising Chris Martin, Guy Berryman, Will Champion and Jonny Buckland - are presently working on their long-awaited fifth album and love experimenting with playing them in different ways, with often surprising results.
Their Roadie #42 blog explained: "Chris suggests playing a gorgeous melody as though they are a metal band. The first stab at this is predictably (and intentionally) comedic.
"They pursue it though, playing one section over and over in a loop, varying the dynamic from pin drop quiet to aggressive and bolshy. They move through the transitions as one unit, as though someone is pressing their foot smoothly on some huge gas pedal somewhere."
Ash frontman Tim Wheeler has been working with the 'Fix you' hitmakers on an as-yet unnamed track, and the roadie revealed the music he completed with the band was based on a small improvisation the 'Oh Yeah' singer came up with when practicing.
The blog explained: "Tim straps on a guitar and jumps into the day's tune. He's fiddling around at the top of the neck, looking for melodies, just throwing out streams of notes.
"Chris starts to call over the mic 'What was that?'. He sings a tiny snippet of something that Tim played only once - almost as something to just get his fingers moving.
"It's such a tiny cluster of notes that for a while it's unclear where they should fall in the chord sequence until finally they drop into place and twinkle like they've been there all along, just waiting to be discovered."