Bass player Joel Beeson explains how if will work: "Certainly to start the song they will be thrown in the deep end. But we'll have our mics on still, if they need a little helping hand with this or that. And maybe some people might feel more comfortable to get up with a friend and sing it as a duet. There are no rules really."

It's a party game the lads have not jumped into without some trepidation.

"It sounds really fun and exciting. But it could also be really tragic. Though I think it will be spectacular either way."

Indeed, crowd participation can mean things could go wrong - like people not wanting to sing or others who will get up and just go a little nuts.

"Both [situations] are equally terrifying," says Beeson. "You know, there is always the chance that someone that jumps on stage could just be somebody that wants to yell out to their mates. You know, 'Damo, I'm on the stage. Damo!' That's not going to be fun for anybody."

The wild idea, that is sure to see some stellar crowd heroics, came about during a late-night planning session for the band.

"It was the culmination of a really long meeting that we had in the middle of the night because Simon lives in Berlin. And after discussing everything else, we were thinking, 'What are we going to do to make this tour more interesting?'

"And someone said, 'What about karaoke?' And I think at that time of the morning even the stupidest ideas everyone gets really enthusiastic about, so we rolled with it, and we announced it. And now we have to work out how to actually do it."

The plan is to play a normal set, maybe letting some people up to sing one or two of their tracks, and then close out the night with the audience showing off their musical skills more fully.

"What we're trying to do, we're trying to learn as many of the songs that people have suggested that we should play and have a shortlist of 20 or 30 and then come back for a second set purely as karaoke, where people can choose one of the 20 or 30 songs from the short list and we'll play it. It's really daunting."

Though crowd participation is something the Philly Jays are pretty used to.

"Sometimes you're just instinctively drawn to the crowd, if there is a really good vibe," says Beeson. "There have been times where someone has jumped up on stage and danced and it's ended up with 50 people on stage and we're just down in the audience watching this craziness happen."

Philadelphia Grand Jury

When: Friday, June 3

Where: Transit Bar

Tickets: $15+bf from moshtix.com.au.