Nicky Wire has kept one polythene bag bearing the shop's name, Martin Luther Records, a souvenir of his final visit to the old stamping ground of the four friends who would grow up to become Manic Street Preachers.
"You would have found us at the rack marked R for Roxy Music," he says.
"Their album sleeves were the only pornography available to lads from Blackwood, Wales. And R was conveniently right next to S for Carly Simon. I used to stare at the shot of her on her knees on the Playing Possum cover for whole afternoons. And what was that other LP of hers, the one featuring her in that tight T-shirt?" No Secrets, I say.
"Ha, that was it! But listen to us - what a couple of pervs. What were we talking about before?"
Let's see: the death of the record shop and the closure of the Cadbury's factory in Keynsham. The lack of bands writing about Tony Blair, New Labour and Iraq, the lack of bands reacting to the recession, the lack of bands with magic or even a bit of good old-fashioned nihilism - and the rise of the middle-class rocker. In short, the end of a lot of what Wire believes in.
"It breaks my heart that almost a whole generation of bands is totally disengaged from what's going on," he says.
"It's a generation born of complete hedonism. They've had ten years of economic growth and the virtuality of the internet and they've gone soft and fat. Where are the songs about the economic desolation and the surrealist construct of the banks being the only nationalised industry under Labour?"
The coalition government may still be too new to merit a musical response, but that doesn't stop Wire having his tuppence worth. "Nick Clegg has got this disingenuous snakeyness. He reminds me of David Brent; a third-rate motivational speaker."
Always mouthy but highly articulate with it, he also lays into Ben Myres, author of Richard, a fictionalised retelling of the last days of missing-presumed-dead Manic Richey Edwards. "I found it too upsetting to read. Richey was - is - a brother, a son, a friend."
So, no evidence of the surviving three going soft and fat. After 20 years - "It's so hard to be a guitar band now," says Wire - they could almost be forgiven for album number ten being a greatest hits for one last cash-in tour. But that wouldn't be the Manics' way so Postcards From A Young Man is big, blousy, angry, cuddly, defiant and nostalgic.
Summoning the spirit of Dylan Thomas, Wire, now 41, describes the record as a "rage against the dying of the light".
Golden Platitudes is a rage against New Labour - "Oh what a shangri-la, oh what a shower we are, oh what a mess we've made, what happened to those days when everything seemed possible?" - and the most political track. "I had to check myself, I didn't want to bog the album down." But, typical of the band's everything-and-the-kitchen-sink approach, this song finds room for a chord sequence homaging Take That's Back For Good. "We've never been music snobs," says Wire, who once defended Gary Barlow's honour when the Thatters were slagged off by Arctic Monkeys.
"I remember playing Top Of The Pops with Take That and Robbie Williams cadging fags off us." He loves a reminisce. "Top Of The Pops used to be the ultimate. Now it's getting your music on iPod adverts."
For his love of a sentimental melody he doesn't blame his mum Irene; he thanks her. "She used to play Abba and Neil Diamond all the time. I'm a proper mummy's boy and I don't mind who knows – a real bedroom boy when Richey, James (Dean Bradfield] and Sean (Moore] were already going to gigs. She had a great trick of writing to St David's Hall, Cardiff, saying I was too ill and could the bands write back. I got a reply from the Mary Chain - Bobby Gillespie signed it 'from Jesus Christ' - and Morrissey wrote 'Get well soon'."
The postcards the Blackwood boys would later send to each other gave the Manics the album's title. "We've always written," says Wire. "When I was at uni in Swansea there was a queue at the pay phone every time so I'd nip into Athena for a postcard of The Scream or Beatrice Dalle and write the boys a few words about my day.
The ones I got back from Richey and the others, also my mum and brother, are these oddly loving communiques where we were at our most honest and I treasure them."
Mention of the luscious, pouting Dalle brings us full circle to Martin Luther Records where various factors combined to produce a band as chippy, passionate and melodramatic as the Manics.
"We didn't have much money. I paid for Simple Minds' Sparkle In The Rain in 50p instalments, so that kept us hungry for music. Now it's everywhere and free. But this democratisation of music, of everything, isn't good. The book I'm reading is called The Shallows: What The Internet Is Doing To Our Brains. Everyone just skims now and it feels like virtuality is the next stage of evolution.
"Also, being working-class from, at the time, deeply unfashionable Wales, we had to struggle to get heard: that's why we started out so over-the-top and hysterical." These days, thanks to Gavin And Stacey and Michael Sheen, being Welsh is cool, although he reckons there are even more middle-class bands than before. "They view rock'n'roll as an 'option', like a gap year."
But, from having fewer options and less of everything, the Manics are still here. Proof, says Wire, of the awesome power of the postcard - it beats an app every time.