How exactly is As The Palaces Burn by Lamb of God a groove-metal album? That's what wikipedia says, at least. But when I listen to it, it seems pretty definitively thrash. Apparently I don't know what thrash metal and groove metal are.
I think I understand a couple of things... like black metal, death metal (maybe), and doom metal. And I THOUGHT I understood groove metal but I obviously don't. That may go for Thrash as well.
So are there really specific ways for defining the metal subgenres, or is it just a "you know it when you hear it" thing?
To be honest with you, I never really understood what Lamb of God's real genre is, I'm guess it's just metalcore. The vocalist does sound kinda like he's yelling in a metalcore styled voice, maybe the band is a combination of thrash and metalcore?
I don't know what groove metal is either, in fact I never even heard of the genre.
Thrash metal is stuff like Metallica, Megadeth, Metal Church, Slayer, Annialator, Exodus, and so on. Thrash metal songs usually consist of solos and guitar focused metal. Thrash metal is about as rocky sounding as it gets for metal.
If there's any other questions you have for the sub genres of metal just ask us, we'll try to help.
So are there really specific ways for defining the metal subgenres, or is it just a "you know it when you hear it" thing?
It's kinda like this. For example, you know that black metal has a vocals sound that is the "norm" for Black Metal (Darkthrone and Burzum are good example for the "norm" sound of black metal vocals in metal). If you hear a band that has black metal vocals, then you hint in that it's black metal. Black metal also has a guitar tone that is "normal" for the genre, check out Darkthrone again for a good example of the norm for black metal toned guitars.
For Death metal, you can tell by the growling vocals or by the rougher than normal guitar tone, cause that is the norm. Get it kinda?