All of this, if you'll excuse me, is points on a graph. Humanity, bands, music, we all bumble along an x-axis with time gnashing at our heels, before eventually falling off the end, into a dark infinity beyond mathematics. But life, life is what happens on the y, the highs and lows chalked up on the grid in complex constellations. We grow up. We graduate. We land jobs, and we lose them too. And pop-punk, so-called here because I'm bored of censoring my own crassness, is apparently something we are growing into again. Whether it's become less boring, less puerile, or whether we're just realising that we're also boring and puerile, is anyone's guess. While it's only really been a year since they offered up their self-titled debut, on second full-length Surfing Strange Philadelphian foursome Swearin' sound a little like they've been growing older - and more miserable too - modifying their formula for that genre to suit.

For a start, the band no longer sound like they've spent their studio downtime getting loaded on fizzy pop and jumping on the sofa. Much of Surfing's execution is loose and rangy, characterised by slack, grumpy tempos and an emphasis on guitarist Kyle Gilbride's laconic, all-American sneer over axe-partner Alison Crutchfield's more obvious tunefulness. That this is Gilbride's album (where Swearin' was undoubtedly Crutchfield's) is apparent before the man even sings a note, from the moment his guitar spews warping voltage over Crutchfield's thunderous, anthemic swing on opener 'Dust in the Gold Sack'. The song is a convenient dividing line, on which Swearin' dovetail the toothsome sugariness of their first record into Surfing Strange's self-conscious, disenchanted oddness - while 'Dust in the Gold Sack' ends on a wonderful, drunken chorus of broey chanting, it's prefaced by those wonky, growling leads, and Crutchfield singing of dirt where there should be treasure. The following 'Watered Down', dudely grunge frayed to the point of falling apart, is similarly brimming with the rhetoric of the beaten; it's a stoned, wry chuckle into the big empty, equal to anything the Lemonheads released at the depths of Dando's despair. As Gilbride listlessly intones "I hope you're right" over the meatgrinder chords that close the song, we know that he's dispensed with hope already.

It's not until 'Mermaid', though, that the extent to which Swearin' have mutated becomes wholly apparent. The song's hulking wall of sludge, bereft of chorus (hell, largely lacking vocals at all) and advancing at a muddy crawl is about as far from Swearin''s exuberant suckerpunches as the same band could get without descending into gimickry. Surfing Strange is littered with moments like this, songs which catch you short and wondering what weird locale you've stumbled into. 'Glare of the Sun' is the most obvious culprit, a palindromic nugget of psychedelia that comes off like one of the druggier cuts from Elliott Smith's latest days, a gangly, bass-driven centre encased in parentheses of fizzing distortion. Similarly (but, y'know, not too similarly), Crutchfield frames her snarkiest hooks this time in a hushed strum reminiscent of her sister's much-lauded project, as she deadpans on the frighteningly bare 'Loretta's Flowers', "when you grow up, you'll realise this wasn't love - or you won't, and you'll remain ignorant and in pain." OK, so the song lacks the juxtaposed thrills that once framed equally cruel lines like "I hope you like Kenosha so much you stay there forever and we all lose touch," but it hits just as hard for its unprecedented starkness. I'd commend Swearin' for bravery in their branching out, if I thought that Surfing Strange didn't embody, in all its bizarre u-turns and boiling apathy, that most wonderful aspect of bandliness - simply not giving too much of a fuck about what anyone else thinks.

Of course, all this adventure can work to the record's detriment. There is nothing as instantly addictive as 'Here to Hear' or 'Kenosha' on Surfing Strange, and from a fanboy P.O.V. if not a critical one, that smarts a little. The tellingly-titled 'Young', penultimate track and really the first upbeat number to feature Crutch on vocals since 'Dust in the Gold Sack', will be like manna from heaven for anyone jonesing for the saccharine jolts of last year, its atonal squall of an intro swiftly giving way to the sunniest, jangliest, Swearin'iest two minutes on Surfing Strange. That said, though, it doesn't come out on top here - Surfing's real aces lie where Swearin' marry their newer, more morose tendencies to the fearsome energy that made them great in the first place. 'Unwanted Place' is probably the peak of it all, the youthful abandon of the band's debut hammered into new shapes by slashing rhythms, the truth portrayed as something negative, and a tree-felling power riff that has a stab at rivalling its antecedent in The Post. Anyone who's seen the band live recently will attest to the destructive power of 'Echo Locate' - Gilbride's voice, his campy rolling of 'r's and nasal drawling of vowels, is perfect for the song's "reading trash rags" hook, and when he and Crutchfield team up at the song's close, spitting "makes no difference now" over some truly horrible guitar tones, it's impossible not to be convinced, whatever it is they're singing about.

As Gilbride keens on closer 'Curdled' (two and one-half minutes of quiet, flame-gutted beauty), "critical shifts make the blaze decay/ritual rots, then you come awake." Everything, music, human, or whatever, risks its dips on the y-axis. When they're laid out like Surfing Strange, though, a thorny, gorgeous mess that encompasses misery, happiness, love, hate, getting high and getting bored, it's difficult to mind all that much.