The problem with many symphonic bands is that they compromise a little on the brutality to maintain the symphony. It's the rare band that manages to pull off beauty and brutality in equal measure. One such band is the Italian technical death metal band Fleshgod Apocalypse.
'Agony' is the album where they truly come into their own. IMHO, it is a truly amazing album, and they are a vastly underrated band.
Check them out:
Temptation (intro) followed by The Hypocrisy: http://www.youtube.com/watch?v=Fee9ORFAOlE
The Violation (their only music video): http://www.youtube.com/watch?v=xjKyzwqIT7s
The Betrayal: http://www.youtube.com/watch?v=2xPBAiHaT-0
Just three of my favourites, but the entire album is breathtaking. It should be listened to as an organic whole without gaps in between the tracks. And you need a really good sound system to pick up all the nuances - there's very complex layering. Youtube definitely does not do it justice.