Sigh's fifth album and most ambitious work to date, Imaginary Sonicscape solidifies the band as a master of surrealist black metal, even if there isn't exactly a whole lot of competition.

With it, they have kept the main elements of their last couple of albums intact -- the dirty, hook-filled '80s metal riffing; the female choirs and (very realistic sounding) synthesized string sections; and the grim, scratchy lead vocals of frontman Mirai Kawashima -- while at the same time greatly improving the production and expanding the instrumentation to include, most notably, a whole array of vintage '70s keyboards (e.g., Hammond organ, Moog synthesizer, Fender Rhodes piano).

Unlike some of their earlier work, where the rough-edged guitars could seem at odds with the more lush strings, the instruments here are more smoothly integrated and simply sound more natural alongside one another.

That's not to say that their music has become more tame in the process: just about every track contains some sort of bizarre "What were they thinking?" twist, such the out-of-nowhere dub-reggae breakdown in "Scarlet Dreams" or the chorus of giggling babies that suddenly cuts in at the end of "Requiem: Nostalgia." Elsewhere, listeners will encounter bombastic prog rock keyboards, vocoders, Japanese folk music passages, mellow jazz fusion piano, loads of trippy synth effects, and even a little kung-fu-flavored disco.

What makes it all even more disorienting is how everything remains tied to a more-or-less straightforward, hard-rocking metal foundation, the kind that would do Thin Lizzy or Iron Maiden proud (especially with all the dual-harmonized guitar lines they toss in this time around).

On one hand, this is great heavy metal, and on the other, it's genuinely twisted experimental/psychedelic music.

An amazing, weird album, and also the best place for newcomers to start with this band.

[The 2007 edition includes one bonus track.].