While guitarist John Douglas acknowledges the Trashcan Sinatras’ 30th-anniversary acoustic event this Tuesday night at the Metro Music Hall in Salt Lake City will be a stripped-down, bare-bones affair, he and his bandmates still have grand ambitions for it.

“We play for a while, we do two sets, we’ve got no support, [play] a couple hours, maybe longer than that depending on the venue, what the rules are, but basically the concept is we just play all night,” he said. “If the doors are at 7, we’ll be onstage at 8, and we’ll be there ’til 5 or 6, so get something to eat or go for a drink if you want, because we’re not going anywhere!”

Fittingly, the show is billed as “All Night With the Trashcan Sinatras,” and, for what it’s worth, the event’s listed time is 6 p.m.

The Scottish alt-rock band burst on the scene in 1990, as the hit single “Obscurity Knocks” rose to No. 12 on the U.S. Modern Rock chart, helping to keep the Sinatras’ debut album, “Cake,” on the Billboard 200 for a solid three months. Their lone top-10 U.S. hit, “Only Tongue Can Tell,” came from the same album. Their last song to chart in the States was “Hayfever,” which got to No. 11 in 1993.

Trashcan Sinatras

When • Tuesday, 6 p.m.

Where • Metro Music Hall, 615 W. 100 South, Salt Lake City

Tickets • $20; Ticketfly

Still, the band has maintained enough of a following, in spite of subsequently infrequent album releases, that Douglas, fellow guitarist Paul Livingston and vocalist Frank Reader — half the band’s official lineup — could, on the spur of the moment, book a five-week, three-piece U.S. acoustic tour.

“That was a kind of last-minute decision we weren’t planning. We toured as a full six-piece band last year, and this year we weren’t really planning on doing any touring,” Douglas conceded. “But Frank, our singer — I live in Glasgow in Scotland and Frank lives in Pasadena, and Frank spent the summer in Glasgow with me and we got charmed, and he said he basically wanted to go and sing. He was getting a bit … he felt his abilities were not being used and he wanted to go and sing. So we thought, ‘What’s the quickest way of doing some shows?’ And we decided, ‘OK, well, let’s do it, let’s do it,’ and kind of traveling light, with the band basically cut in half.”

In April 2016, the Sinatras released their first album in seven years, “Wild Pendulum,” which has spurred the band into a period of business.

Douglas said that while he, Livingston and Reader, the band’s three songwriters, are always kicking ideas around, their impending 30th anniversary as a group helped inspire the new album’s the subject matter.

“I think this batch of songs are reflections on age, the passing of time, a bit of storytelling as well,” he said.

That said, Douglas is actually a bit surprised the group even made it to the three-decade milestone at all.

“It wasn’t something that was anticipated — definitely not. We always seemed to take things week by week, and song by song, to be honest. It means a lot to still be here,” he said. “It seems like something kinda natural in a way — it’s quite a slow process of working. So even though it’s 30 years, there’s only six records. So, in a lot of ways, it still seems as though there’s things to do. We’ve always been driven by songs. Even when there’s only one or two, that’s always given us the impetus to carry on. But no, never in a million years would I have said longevity was part of the thing. But it feels great to still be here 30 years on and still be friends and still admire each other for what we all bring to it individually.”

With more than 100 songs in their repertoire now, Douglas said everything was on the table for these acoustic shows.

He said the band was making it a point not to play the same prefab setlist every night, in order to bring a sense of spontaneity to each individual concert and to ensure the performers are “just relying on your basic abilities.”

It’s an ambitious approach, but one he thinks fans will appreciate.

“They can expect a few surprises, to be honest. … We’ll play whatever, we take requests before the show, we’ll play things from every record that we’ve done,” Douglas said. “We try to keep it refreshed for ourselves, so until the day we arrive, we won’t know precisely what the setlist will be.”