drum and bass beats are not always based on sampled breaks at this point. much of it uses completely synthesized sounds, even down to the drum hits. it's broadened (and also narrowed too in some ways).
basically, if it's 160-190 bpm, has a breakbeat in it (the bass drum is not hitting on 1 2 3 4 or 1 3, but rather some syncopated pattern)...it can probably be called drum and bass.
there's a LOT of subgenres, but I tend to be kind of a generalist, although a lot of the newer british "pop" drum and bass kind of drives me up the wall.
anyway, check out Remarc, Black Sun Empire, John B, Evol Intent, Noisia, Soundmurderer, Amen Andrews, LTJ Bukem, General Malice, Phace, Teebee, SolID, Autumn...that's a pretty good spread of different drum and bass styles there. Every last one of those artists will sound different than the next.
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