Pink, Carling Apollo, Manchester<br></br>Underworld, Brixton Academy, London

Why you'd crawl over 100 Pinks to get to one Britney

Just what the hell are "frustrated fears", anyway? Surely, by their very nature, if they've been frustrated, then they're no longer fears and, in being thwarted, have been downsized into mild worries or something. Of course, I realise you shouldn't try being Mr Logic with pop lyrics – can open, worms everywhere – but Pink is beyond the pale.

Whatever "frustrated fears" are, the person Pink addresses on her international mega-hit "Just Like A Pill" makes her want to run to the middle of them. Well, I guess she intends some conceptual fusion of "frustration" and "fear", but by converting the former into a past participle, she murders the meaning. This kind of muddy thinking is typical of the wave of Issues Rock which broke in the States with Alanis Morissette, and which I'd prayed had ebbed away. Over here, Music Therapy just means a charitable project run by Nordoff-Robbins. Over there, it's a whole industry. Right now, Pink is its undisputed queen.

"I believe that music is freedom," Pink tells Manchester, her legs slung around a backwards chair in time-honoured Christine Keeler pose. "And you can do whatever the hell you wanna do." She's right, of course. Pop is a zone of unlimited possibility, which is why it's somewhat depressing that Pink has settled for middle-of-the-road pop-rock.

When she first appeared, a protégé of Anthony LA Reid, she was a promising R&B princess, another Kelis or another Eve. On "Most Girls", the song which launched the phrase "bling bling", she boasted of her autonomy: "Shorty got a job/Shorty got a car/Shorty can pay her own rent" (she isn't joking either: I stood next to her once at a party, and she's tiny).

It was her second album, Missundaztood, which catapulted her into the mainstream. She – or Reid – achieved this by hooking up with songwriters like Linda Perry from the appalling 4 Non Blondes, and writing songs which depicted Pink as a walking car-wreck, a hospital case, "a hazard to myself". It's a transition which she was always destined to make. Pink was always suspiciously well-placed to make this crossover: the world's whitest-looking black woman (now sporting the world's blackest-looking pink hair). She can't help her physiognomy or her racial mix, but you have to wonder whether this, and not any inherent talent, which Reid first spotted.

Similarly, it barely matters whether or not the traumas she sings about are genuine. The fact is that they're marketable, and judging by tonight's evidence, Pink has connected with a massive and largely female audience who also want to run to the middle of their frustrated fears. Or simply enjoy feeling slightly naughty when shouting "just a little bitch!".

"Get The Party Started" is a fine if obvious opener, and "There You Go" is a reminder of her fly-girl past. The rest, though, is endless middlebrow middle-Americana. Stomping about the stage in skater gear (baggy shorts, keychain, DMs, white vest), she's a talkative so-and-so, giving every song a rambling intro. When she says the words "Linda Perry", my heart sinks. I hoped I'd see out my threescore-and-who's-counting without ever needing to hear 4 Non Blondes' revolting "What's Up" again, but I was reckoning without Pink at the Apollo.

The slideshow which accompanies some songs hints at an ego out of control. "My Vietnam" combines a near-meaningless montage of images of 'Nam with big, capitalised words like "FREEDOM", "PEACE", "AGEISM", "UNITY" and (weirdly) "GAY". "Family Portrait" takes the literalist approach (tearjerking happy snaps). A gallery of dead legends – Joplin, Cobain, Biggie, 2Pac, Joplin again, Hendrix, Carpenter, Aaliyah, Joplin again – runs as she sings a medley of Gershwin's jazz standard "Summertime" and Erma Franklin's "Piece Of My Heart". The implication – that this rinky-dink Pink panther is up there with the greats – is as plain as your nose.

Even that couplet in "Don't Let Me Get Me" that goes "Tired of being compared to damn Britney Spears/She's so pretty, that just ain't me" reeks of false humility. Of course, she's right to a degree, in that you'd crawl over 100 Pinks to get to one Britney, but let's face it, if you didn't make it all the way, it wouldn't be the worst thing that ever happened.

All those young minds, all those psychoactive drugs, and all you're going to give them is music for the body? Dance culture's emphasis, from Acid House onwards, on the physical over the cerebral meant that if Underworld did not exist, it would have been necessary to invent them. Not that they're drily bookish or wordy, nor are they incapable of affecting the body: the waves of euphoria that roll over me when I hear "Two Months Off" have little to do with the lyrics. But Karl Hyde's abstract, punctuation-free prose-poems have more in common with, say, Burroughs or Smith (Mark E) than with Mr bloody C.

The Brixton Academy isn't filled with people intent on deconstructing the text. They're here to drink and dance and get on one and shout "lager lager lager", and Underworld give them what they need. There's a circular paradox which dictates that very hi-tech is very lo-tech: the more experimental you get, the more primitive. This apparently applies to Underworld's banks of gear. The shaven-headed, enormo-headphoned Karl Hyde dances like a Harry Enfield parody of old skool rave dancing and spews his streams of consciousness, to visuals, courtesy of their own film company Tomato: the kind of smoke the SAS might use to storm an embassy, retina-boggling assaults of binaries and matrices, Xs and Ys, zeroes and ones on the big screen, and lasers which momentarily make everyone's heads resemble little fishes, like a theatre full of neon tetras. Underworld are a band who can engage your brain, dazzle your eyes, and make you dance like a tropical fish. You can't ask for much more.

s.price@independent.co.uk

Pink: Birmingham Academy (0870 771 2000), Mon; London Brixton Academy (020 7771 3000), Tues. Underworld: Bristol Academy (0870 771 2000) Mon and touring