When Stuart Braithwaite and his band Mogwai unleash their thunder in a tent on the southside of Glasgow next month they’ll be playing like they’re inside outside.

“It’s not fully outdoors, so we don’t need to compromise on the sound,” said the frontman of Scotland’s loudest rock band. There are a few other outdoor places in Glasgow you can play that are great for gigs, but maybe not for us because we’ve definitely got to be loud otherwise people will find out how crap we are at playing. That’s how we disguise our ineptitude.” Braithwaite’s tongue is in his cheek, of course, and his band will be in a tent.

The big top has become a fixture of the southside summers in Glasgow’s Queen’s Park recreation grounds over recent years. This summer the tent will see the likes of The Charlatans, Callum Beattie, The Waterboys and Admiral Fallow perform under canvas, with a new one-day festival south of the river, Big City, curated by Braithwaite and his bandmates. The all-dayer will feature Nadine Shah, Kathryn Joseph, Sacred Paws, Slowdive and a headline set by Braithwaite’s band, whose Rock Action label is home to most of the line-up. The Queen’s Park ducks might think about going to visit their cousins at Maxwell Park for the night and make a repeat booking for the following year.

“We’re hoping to build on it. We want to do it every year. We don’t want this to be a one off. We have a list of bands we are hoping to get for next year as well,” said Braithwaite.

The Glasgow band have form for curating festival line-ups, being the creative force behind the roster at the now-defunct All Tomorrow’s Parties indie hoolie in Camber Sands, which ran until 2016.

“I was really proud of our association with All Tomorrow’s Parties,” said Braithwaite. “And I think there’s something like that about this, and that’s something  that has been missing for a while – something curated by artists and not created by booking agents. No harm to booking agents but bands know more about music. It’s a hard climate for festivals. People don’t have as much money as they used to. A festival is a luxury for most people and I think it’s quite a challenging environment. But there’s a lot of good stuff happening in Glasgow this summer and we’re really looking forward to this.” 

The only downside, perhaps, is that Young Fathers are performing in Stirling’s Summer Sessions on the same day, something Big City performer Kathryn Joseph says is “strange programming”.

“I’m broken hearted they’re on the same day, because everyone at either gig would want to go to both,” she said. “But I’m delighted to be part of this one. Everyone on the bill is a favourite of mine – Sacred paws. Slowdive, Nadine Shah. I actually can’t even believe I’m saying all the names.”

The roots of Big City can be traced back to Braithwaite’s experience of Primal Scream’s gig at the Rex (as the recreation grounds are known colloquially to locals).

“I went and played some records at the Rum Shack round the corner and loads of our pals were there,” said Braithwaite. “Bobby Gillespie came and hung out there afterwards and the whole thing was just a great vibe. We don’t live in the south side, even though most folks seem to these days, but it feels like the artiest bit of Glasgow.  It’s a really nice spot for this kind of festival. So after that Primal Scream gig I spoke to Regular Music about the idea of a big festival in that tent, and it went from there.”

Having been around for almost 30 years, Mogwai – named for the cute critters in 80s sci fi horror classic Gremlins – have been surprised by the timeshift which has seen them accrue the status of elders. They’re currently working with American producer John Congleton on their eleventh album, being recorded at Chem 19 studios in Blantyre. “We were a lot younger than most of the other bands when we started,” said Braithwaite. “Our first album came out when we were 21. We did End of The Road Festival (in 2011) and a lot of the younger bands were watching us, and they came and spoke to us afterwards. It never occurred to me until then we were an ‘older’ band. 

“When we used to play lunch time at a festival we’d be excited about getting to watch the headliner at the side of the stage. That’s us now. And that’s great. But I’m not quite knocking about with my thumbs hooked into my braces. When we started the band we were just wee guys. The idea of being alive when you’re 50 is pretty surprising never mind being in a band with the same people that you were in a band with when you were 19,” said the frontman, two years shy of his half century. “It’s terrifying on one hand, how did this happen? But on the other hand I love being in this band and I like being with all the other people in the band and the music we make. There’s nothing to not like about it.”

More than that, every note at every gig is an exercise in blessings counted. “To be honest, I’m very grateful to be alive,: he said. “I still feel 25, but I’m getting to the age when some people, some pals, they get sick, things happen to them, so you definitely appreciate what you’re doing when you get to this age. I look at The Cure and they are super-inspiring. Their gigs are twice as long as ours and they’re a lot older than us. It’s clearly doable, if you make an effort to not stop. I think our generation aren’t willing to surrender to old age. It’s more about having a good time and a sunny outlook.”

And wearing ear protection. “I think music should be a physical experience, certainly the kind of music we play,” said the man responsible for Scotland’s loudest band. "But it can be risky for your ears, so get some earplugs. I wear them all the time to gigs. People should look after their ears.” 

Big City, Queen’s Park, Glasgow, June 29