In metal circles, the very name Opeth tends to arouse very strong emotions. To some, they are nothing but a novelty crossover act, a bunch of opportunists watering down their sound from "true" heavy metal to appeal to the masses. To others, they are pioneers, taking death metal and prog metal from the more or less stagnant state that they've been in for the past decade or so and bringing them to new and interesting places.

As a music reviewer and more importantly a fan of heavy metal, I'm firmly in the latter camp. There is one thing to be said for stylistic purity, but it's also important that metal keeps on pushing forwards and onwards to avoid becoming stale and to seed the ideas that will result in tomorrow's micro-genres. So, I support Opeth's quest to shake things up, and their latest album, "Watershed", certainly does that.

It's hard to tell at this point whether "Watershed" will actually be a watershed album of course, we'll have to wait a few years before we can look back and honestly assess the impact that it's had on the scene, but all indications are listening to it in the here and know that it might very well be. This is still unambiguously death metal, and if you needed any convincing of that then the ferocious heavy passages on songs like Coil and The Lotus Eaters should put your mind at ease. These passages are vintage Scandinavian death metal, with just enough prog-metal via Mastodon and Dream Theater mixed in to keep things interesting.

But I suspect that most people who listen to Opeth now are not doing it for the heavy passages, they're doing it for the far more interesting and unpredictable stretches in between them. The band delivers here, with a mixture of acoustic sections, interspersed male and female vocals, and piano pieces. It all retains the atmosphere of grim resignation that has characterised most of the band's work to date (as well as their album covers), but the delivery here is a lot more mixed up and varied, and it's done in a good way.

Some will say that the impressive integration of the brutal and the mellow is due to the departure of stalwarts Peter Lindgren and Martin Lopez, but after a few listens to "Watershed", it becomes apparent that this is the sound that the band have been evolving towards for quite some time. The change on this album feels natural and unforced, and it provides yet another thought provoking preview of what the future of heavy metal might look like.