Unlike how Dnite described it, sludge is NOT doom and stoner
metal, sludge is unique from those two genres of music. but takes a lot of influence from them. sludge builds upon doom
metal, by adding highly distorted guitars and vocals reminiscent of hardcore
punk.(yelled, or shrieked, rather than sung or growled) Often mixing in slight blues influences as well. Has a sort of fuzzy sound, with often very melancholic lyrics.(lyrics about drugs, are not uncommon). Dnite did get one thing right, tho, sludge
metal does take high influence from early bands like the melvins.
Such
sludge metal bands include bongzilla(mix of
sludge and stoner), fistula, crowbar,rwake, and electric wizard.