Keith Richards has been "playing a lot of bass" on The Rolling Stones' new material.
The 78-year-old guitarist and occasional bassist has recalled spending a week in Jamaica with frontman Sir Mick Jagger, also 78, jamming and working on new music for their new studio album, and him playing the four-stringer added "another angle" to their sound.
According to the Daily Star newspaper's WIRED column, he said: "I was in Jamaica with Mick (Jagger).
"We were spending a week together putting material together and hanging around."
Quizzed on how many songs they have, he continued: "More than I can count - it was a very productive week.
"We had a setup there, bass, drums, and we got a very good sound going.
"Jamaica is good for sound."
The rock 'n' roll icon insisted the 'Start Me Up' hitmakers - who famously recorded 1973's 'Goats Head Soup' in Kingston, Jamaica - haven't tread too far from their roots.
Keith - who is also joined by 74-year-old bassist Ronnie Wood in the band - added: "I was playing a lot of bass so it was taking on another angle.
"It's quite interesting - at the same time it's Stones man.
"It was great fun and we are gearing up for Europe shortly.
"Once a year I like to keep my hand in - there's nothing like playing on stage."
The upcoming LP will be the first new music since the death of drummer Charlie Watts, who died last summer aged 80.
Keith recently revealed he and Mick had "eight or nine new pieces of material", which they worked on with 65-year-old touring drummer Steve Jordan.
Appearing on 'CBS Sunday Morning', he spilled: “It’ll be interesting to find out the dynamics now that Steve’s in the band.
“It’s sort of metamorphosing into something else. I was working with Mick last week, and Steve, and we came up with some, eight or nine new pieces of material. Which is overwhelming by our standards. Other times, [songwriting is] like a desert.”
When quizzed on why penning new music can be challenging, he coyly replied: "It’s the muse thing. If I could find her address (laughing).”
The 'Paint it Black' band's last album of new material was 2005's 'A Bigger Bang'.
The Stones have just announced the dates for their 60th anniversary European and UK tour.
The 'SIXTY' tour will see them play Liverpool's Anfield Stadium on June 9, and two nights at American Express presents BST Hyde Park in London on June 25 and July 3.
It will mark their first concert in Liverpool in over 50 years, the last time being at the Empire Theatre in 1971.
The jaunt - which follows the 'No Filter Tour' - also includes shows in Munich, Brussels, Vienna, Lyon, Paris and Stockholm.
