Although the terms death metal and black metal are often used interchangeably, the two are not identical any more than ska and reggae or merengue and bachata are identical.

But it is certainly safe to say that death metal and black metal are very close allies and share a lot of common ground artistically.

Death metal fans are often black metal fans, and it is not uncommon for a band to combine the two -- which is exactly what happens on Vile's third full-length album, The New Age of Chaos.

This 2005 recording is death metal first and foremost; lead singer Juan Urteaga favors the type of deep, guttural, menacing growl that death metal is known for.

But Vile does, at times, incorporate black metal elements, including blastbeats, ominous harmonies, and rasp vocals (which are used to complement Urteaga's growling).

Of course, Vile (an American band with a very Nordic-influenced approach) isn't the only death metal unit to incorporate black metal -- there are numerous Scandinavian bands doing this type of thing.

But lyrically, The New Age of Chaos is more ambitious than the average death metal disc; this highly conceptual effort revolves around the theme of an all-out World War III with the West on one side and fundamentalist Islamic terrorists like al Qaeda on the other -- and in a post-9/11 era, that scenario isn't far-fetched.

Urteaga, like a lot of death metal vocalists, makes the lyrics hard to decipher without the lyric sheet -- which is regrettable because Vile's lyrics are definitely above average by death metal/black metal standards.

But all things considered, The New Age of Chaos is a decent, if imperfect, example of moshers adding some black metal ingredients to their skull-crushing death metal recipe.