Diadem is a Californian metal-band which was founded by Anthony Prechtel. The label (his label) is Studio December, which was renamed to Studio November.
However it is difficult to classify the band further, since Diadem is influenced by various genres, so you might identify elements of Viking, Black and Death Metal, but they merge quite impressively.
The first release done entirely by Anthony in 2002 is called "Darkness Surrounds", the second album "Crimson Sunrise", following two years after that. Latest release is "Empyreal Dusk" in 2006.

Darkness Surrounds sounds a little more like Black Metal and covers six songs with a total of 24m16s. It is a demo and very hard to find in stores.
So Crimson Sunset is the first 'real' album, and it mixes Black, Death and Viking Metal to compose a unique sound. Anthony does the vocals and guitars, occasionally also the piano. He is backed by a drumcomputer, which is used in a fair way (means one doesn't really recognize it is actually a machine). Playtime adds up to 49m32s, ten tracks.
The latest longplayer "Empyreal Dusk" was released on June 21, 2006, featuring 12 songs (59m41s)! This is the first album Prechtel did not complete on his very own, this time he was supported by Matt and Michael Owen plus Jesse Krasco (he left the band little later).
Most artworks are done by Anthony, check the disc-section at diademonline.com

Visit Diademonline.com for further information and music samples.