Love or loathe them, you have to respect Napalm Death for sustaining such sheer ferocity, intensity, and volume over 14 albums.

Purists complain that the band lapsed in the mid-'90s, sacrilegiously flirting with melody, texture, and conventional rock structures, but Napalm's post-millennial releases have recovered the edge perhaps lacking on records like Diatribes, without going backwards.

As Time Waits for No Slave demonstrates, Napalm Death hold to their core values of extreme noise terrorism while also keeping things fresh on each new album.

That's evident, for instance, in the atmospheric elements punctuating the assault: ominous vocal coloring on "Fallacy Dominion," dark introductory ambience on "Passive Tense," and a doomy choral conclusion to "Downbeat Clique." Mitch Harris' riffing takes a few atypical turns as "Work to Rule" fleetingly visits black metal territory and the title track's discordant guitar evokes Sonic Youth.

Lyrically, though, it's business as usual.

The state of the world in 2009 obviously isn't cause for cheer, but at least it gives primordial growler Barney Greenway plenty to rant about: "Life and Limb" denounces torture as Embury and Herrera's rhythm section veers between Swans-like pounding and explosive acceleration; "Strong-Arm" embraces nonviolence; "Diktat" attacks the policing of morality; and the title track rages against the capitalist machine.

"On the Brink of Extinction" even tackles ecology and evolution.

Ironically, while the punishing music and Greenway's indecipherable, violent delivery suggest otherwise, the sentiments behind many of these songs are actually no different from those once expressed by docile hippies strumming acoustic guitars.

And although the metal genre is inextricably linked with an alienated, individualist spirit, Napalm have been relatively anomalous in having a communal, essentially socialist outlook, rooted in their original anarcho-punk influences.

Time Waits for No Slave finds Napalm Death keeping faith with their past, albeit without stagnating: within extreme metal's seemingly limited parameters, the band finds modest ways to keep its sound energized and vital.