Although European classical music has influenced progressive metal, it is rare that the metal and classical worlds actually have any type of serious interaction.

But on Equilibrio, the Dutch prog metal band Xystus join forces with the Utrechtsch Studenten Concert Orchestra (the oldest symphony orchestra in the Netherlands).

Xystus' collaboration with Utrechtsch resulted in a live theatrical presentation of Xystus' rock opera Equilibrio as well as the 56-minute studio version heard on this progressive metal/progressive rock CD, which has a science fiction/fantasy plot and is bound to inspire a wide variety of reactions -- some of them positive, some of them negative.

Equilibrio won't win over critics of prog metal and prog rock, who will no doubt call the album overblown, silly, and pretentious and point to it as a perfect example of why punk absolutely had to happen back in the 1970s.

But what is pretentious to one person is ambitious to another, and a big part of Equilibrio's charm is the fact that it doesn't run away from the stereotypes and bloated excesses of prog metal and prog rock -- quite the opposite, in fact.

Performed without the least bit of irony, Equilibrio enthusiastically embraces those stereotypes and excesses and does so without apology.

The result is a well-crafted, well-executed disc that won't appeal to people who insist that they can only handle prog metal and prog rock in small doses but will easily appeal to prog's diehards.

And the fact that Equilibrio represents an actual collaboration between a metal band and a full-fledged symphony orchestra is certainly historic; how many metal bands that call themselves symphonic will ever have any serious interaction with honest to God classical and theatrical musicians? Not many.

Equilibrio is an engaging rock/classical/theatrical collaboration -- excesses and all.