Rockpedia

Compare

Two genres, side by side. The ratings are editorial judgements on a ten-point scale, not measurements. Where they come out level, the difference is in the prose underneath them.

First genre

Post-metal / atmospheric sludge1997

Second genre

Sludge metal1989

Head to headPost-metal / atmospheric sludge vs Sludge metal
Post-metal / atmospheric sludge: heaviness 8, melody 7, speed 3. Sludge metal: heaviness 10, melody 4, speed 3.Heaviness8 / 10Melody7 / 4Speed3 / 3
Each corner is a ten-point rating. The further out, the higher.

The difference, by ear

Sludge has no interest in release. Post-metal takes sludge's riffs and puts post-rock's builds and quiet passages around them.

Sludge metal is growled or screamed where post-metal / atmospheric sludge is part sung, part screamed, and a little slower: 50 to 90 bpm against 60 to 120. Songs run longer in post-metal / atmospheric sludge: usually 8 to 15 minutes, against 5 to 9 minutes in sludge metal. To hear the difference, play Neurosis next to Eyehategod. Post-metal / atmospheric sludge grew out of sludge metal, eight years later.

Put together from each genre's vocals, tempo, song length, key acts and place in the tree.

In figures

Heaviness
Post-metal / atmospheric sludge8
Sludge metal10
+2
Speed
Post-metal / atmospheric sludge3
Sludge metal3
level
Melody
Post-metal / atmospheric sludge7
Sludge metal4
−3

Post-metal / atmospheric sludge

1997 · USA

Where it sits

Heavy metal › Doom metal › Sludge metal › Post-metal / atmospheric sludge

In short

Sludge with post-rock logic: long songs, crescendos and instrumental passages. Neurosis invented the form.

How it sounds

  • Eight- to fifteen-minute pieces with long crescendos in post-rock logic.
  • Delay and reverb guitars for the quiet passages, massive distortion at the peaks.
  • Vocals used sparingly, as an accent, often howled from a distance.

Key acts

  • Neurosis
  • Isis
  • Cult of Luna
  • Russian Circles

Start here

The pickIsis - Oceanic. The most accessible album in the genre, and no weaker for it.

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Sludge metal

1989 · New Orleans, USA · 1 subgenre

Where it sits

Heavy metal › Doom metal › Sludge metal

In short

Doom plus filthy hardcore: feedback, screamed vocals and a guitar tone like Louisiana mud.

How it sounds

  • Thick fuzzed guitar with feedback left running between riffs.
  • Alternation between very slow tempos and hardcore outbursts.
  • Screamed or howled vocals with lyrics about addiction, poverty and rage.

Key acts

  • Eyehategod
  • Crowbar
  • Melvins
  • Acid Bath

Start here

The pickEyehategod - Take as Needed for Pain. The feedback between tracks is part of the album.

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