It was a bit of a difficult answer. I was into the Monkees years before Ducks Deluxe. But I realize that The Monkees got me into the Monkees. My musical interest wasn't moving on from there. With Ducks Deluxe it was different. I came upon an album of theirs (technically, a compilation album) called Don't Mind Rockin' Tonite. I got really into that record, and from there there was an explosion. From the Ducks I moved on to Dave Edmunds. Then Nick Lowe. Then Rockpile, the Motors, Graham Parker & the Rumour, Dr. Feelgood, Wreckless Eric. I could name lots more pub rock bands. And then other non-pub bands that I got into as a result of them. Suffice to say it kind of exploded out from there in many directions. In a manner of speaking, Ducks Deluxe was my big bang of music fandom.
That's not to say that everything I like can be traced back to Ducks Deluxe. There were some small bangs too. The Monkees, I guess, were a small bang (that, as I said, came long before the big bang). So was Twisted Sister (which I got into because of a girlfriend). And Simon and Garfunkel.
But the big bang that opened my world was Ducks Deluxe. I've posted it before but here's a clip of them at their sweaty best: