So Oneida's Thank Your Parents triptych of albums - which began with 2008's Preteen Weaponry and continued with 2009's epic triple-LP Rated O - finally concludes with the bafflingly titled Absolute II. The use of a title that suggests the sequel to another series of records altogether is an apt gesture; Absolute II maintains the challenging sonic, melodic and rhythmic experimentations of the series (and indeed the spirit of Oneida's back catalogue at large), but it differs markedly from those records at the same time. Those first two records seem of a piece, whereas Absolute II is a notable diversion away from their mainly shared sonic palette. The most notable absence is that of drums, which were previously such a vital component, with talented drummer Kid Millions laying down pulsating beats and contributing to the cacophonous swirl of psychedelia at the same time.

It's been left to the pulsating bass to perform all the rhythmic duties as demonstrated by 'Pre-Human', or at least its first half, where the bass is equally economic with melody, buzzing menacingly between two arpeggiated chords which in the absence of vocals have an incantatory effect. Slight stutters in the bass throb and occasional ripples of what could be piano or heavily effected guitar provide the only embellishment on the melodic motif before the throb ceases entirely leaving only gently droning keyboards with a wheezy harmonium like quality as the song drifts through its second half. Textures comes in the form of incidental sounds which ring around and deflect off the main elements, such as the sudden clarity of a trebly bell chime.

'Horizon' displays similar melodic restraint and while its abrasive textures are more akin to those found on Rated O it sounds a good deal less like the output of a rock group. Although beginning with a two-note dirtbomb bassline and a similarly simple synth tinkle, it is only the latter which survives for long, although the melodic elasticity of those two notes is manipulated to extremes throughout. The bass quickly disappears amidst a helicopter-like roar, which becomes the mainstay of the track. Vocals appear, but far from bringing any human warmth to the harsh soundscape they are stuttered and spliced across the stereo spectrum, and syllables and vowels are displaced as if the words are sung through those helicopter blades, although that comparison is rendered useless by the relative distance of the roaring 'chopper' compared with close-up intimacy of the vocals. It's a truly disorientating listen.

'Gray Area' is a continuation of this wilful ugliness. Another synthetic pulse, so taut it resembles more of a mechanic purr, forms the basis of the track which is interrupted by frequent, but irregular, crashes of ugly metallic guitar which set the heart racing Listened to at the wrong (right) time, or in the wrong (again perhaps I mean right) mindset, it's a potentially nerve-shredding experience. Although the core of Absolute II is grotesque in nature that's not to say there's no craft involved, because it is there; it's in the timing of these crashing effects and the rumblings of found-sound that subtly mutate and act as murmurs and echoes of the song's up front elements.

The closing title track consists almost entirely of these sort of incidental sounds, which, given what precedes it, makes for a rather ambient finish. There's nary a melody to be found, just the sort of wind-like noises that you would hear swirling and rumbling through a tower-block in some dystopian sci-fi film. The closest thing to any kind of dynamic or structure is when these sounds occasionally reach crescendo and subsume the foreground, taking on some low-end presence in the process. Fractured guitar notes ring out here and there, adding slightly to the ominous atmosphere.

What Absolute II is supposed to represent in the Thank Your Parents trilogy isn't entirely clear, but then that's to be expected with a group of Oneida's esoteric disposition. For most people this is going to be a tough listen, because it's effectively as inhuman as music gets; little melody, no vocals, ominous moods and abrasive sounds. I can't say if you liked Preteen Weaponry and Rated O then you will like this for sure, because it is a departure. Nonetheless if you were minded to like those two records and if you are after a record that is in pretty much every sense a 'challenging' listen then Absolute II should tick all your boxes.