Next door at Jacobs Pavilion at Nautica, The Beach Boys were starting their sound check for that night's concert, unknowingly drowning out the ceremony with their song "God Only Knows."
"It was awesome and perfectly timed. 'God Only Knows' will likely be our official song now," Diadium told The Plain Dealer.
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When the band was alerted of the wedding next door, they offered free concert admission to everyone attending the wedding — many guests wandered over for a few songs that evening — and even invited the bride on stage to play the tambourine during the encore: "Fun, Fun, Fun."
"I thought about trying to sing along in the mic, but it was best for everyone that I stuck to the tambourine," Diadium said.
Watch the newlyweds gush about their very welcome wedding crashers below: