Opeth's Fredrik Åkesson gave an interview to the site GearGods.net, and if you're a guitar player, you'll probably be fascinated, but if you're not, you could safely skip it entirely.
Regarding the difference between their as yet untitled 11th studio album and their last one, 2011's Heritage, he says, "We talked about [the change in sound] because Heritage definitely has a '70s type sound production wise, so we talked about if we wanted to do an album that had more of an early '80s vibe like Holy Diver kind of stuff, like the early '80s/late '70s type of vibe in the production. The guitars, for instance, on the Heritage album we used single coil pickups. On this one we used a regular humbucker and P90s for the dirty rhythm mix." See how he transitions immediately into guitar talk? The entire rest of the interview is like that, and for musicians, it's bound to be compelling stuff.