So...The Guys From Opeth Claimed DELIVERANCE Is Heavy...

simultaneous 8th or 16th note (sometimes 32nd on slow tempos) phrases on the snare, kick drums, and usually a cymbal (hi-hats, rides, etc.) make up blast beats.

Examples include pretty much any songs by Suffocation, Cannibal Corpse, or Morbid Angel, as well of scores of other Death Metal bands.

There are no blast beats on the new Opeth record. There is alot of continuous 16th note kick work and some 8th note triplets (yee-ahh!), but no blast beats. Martin Lopez is a really good drummer.
 
It's tear your eyeballs out and swallow them, then shit them out into your mouth kinda heavy.

Some brutal stuff, which manages to maintain an overall tone of genuity and emotion. Some stuff reminds me (a little!) of Orchid/Morningrise - some riffs are in the old style.

Expect the unexpected.

And don't ask how I've heard it already (precognition!)
 
Blastbeats have that repetitive banging sound to them. It almost sounds out of rhythm.