Opeth Guitarist Fredrik Akesson admits he had concerns over the band's direction in latest album "Heritage" and feared it might split their fanbase.
But if they hadn't allowed their music to evolve, he's not sure they'd still be around today.
"Heritage" was released last year and its production saw the departure of keyboardist Per Wiberg after an eight-year stay. He's been replaced by Joakim Svalberg.
Akesson thinks that wouldn't have been the only change if Opeth hadn't continued their move away from their extreme metal beginnings and they had no choice but to risk alienating some long-term followers.
The guitarist tells MK Ondergrond: "We thought about it. In the beginning it took me a little while to get used to the new idea of the sound, not having any screaming vocals and stuff like that.
But I think the album was necessary for us to do. Maybe the band wouldn't have continued if we hadn't done "Heritage".
I think the old Opeth fans understand this album. There's always going to be some haters, but you can't be loved by everyone. Opeth has always been about not repeating ourself. A lot of people don't think "Heritage" is metal but I think it's metal to go somewhere people don't expect. It doesn't mean we're not embracing the past sound of Opeth".
The Swedish prog-metal outfit, led by Mikael Akerfeldt, aren't the only band currently looking back in time to find inspiration.
Akesson says: "You have a Swedish band called Graveyard, for instance. There's a lot of bands with seventies, more organic, production.
Classics are always going to be there. When I get drunk I listen to Maiden, Accept, Judas Priest the classic metal stuff. We listen to some death metal as well".