Directioners' parents overhearing One Direction's new single, "Best Song Ever," may have thought it sounded like their best song ever growing up: the Who's "Baba O'Riley" from 1971.

Producer Julian Bunetta opened up to MTV News about the track and that sonic coincidence on Thursday, one day after it leaked prior to its official release on Monday. He said, "Well I mean it starts with a synth and 'Baba O'Riley' starts with a synth. I mean that's a huge compliment because if that can evoke that same excitement than that's amazing but that was not the... we weren't saying 'OK, let's rip off 'Baba O'Riley'.'"

He added, "At a certain point we recognized it had the same type of intro where there's a synth and a piano, but we really tried to make sure that there was no intellectual property stolen or anything like that."

(This is not the first time the young stars have looked to the past for some inspiration. Last year, 1D admitted to paying homage to The Clash's "Should I Stay or Should I Go" on "Live While We're Young.")

So, if "Baba O'Riley" is not the best song ever that inspired the group's new single, just what was?

Well, Bunetta says that's a mystery, even to him. "That's the thing. Have you ever had a night when you were out and you were with friends and you were partying and you were dancing and you were at the height of your happiness and you woke up the next day and went 'That was so much fun... what was that song?' It's just kind of one of those [feelings]," he said. "The song is irrelevant. It's just kind of like at that moment, it's the right thing and it doesn't even matter, all elements added up to being a lasting memory."

The party-like atmosphere of the track is not only felt in the upbeat melody, but also the lyrics of the sing-along chorus. "A moment can mean just as much as any of those [more lasting friendships and relationships] if it's the right moment and in the right setting," he said.

"Then we put it in the context [of the chorus] of [how] it's a little bit of poking fun at pop music, but also embracing it at the same time."

1D, Bunetta and the crew knew they wanted to make the chorus very anthemic, but with "a new spin." He said, "Because there's a lyric in the chorus [where] we're doing the thing in most pop songs now is to have an 'Ooh ooh' [chant] section at the end of the chorus. And we did that, but we sort of like made fun of it saying 'I think this song went 'Ooh ooh.' I think it went 'yeah, yeah, yeah,' but I don't quite remember.'

"We thought it was a clever way to include that because it works so well. That anthemic chant when it's executed right is such a perfect device," he said. "But we all kind if wanted to put our own spin on it."

In the end, the song, and lyrics, referencing steamy kisses and dirty mouths, really embraces just how cheeky 1D are. "Hanging out with the boys and knowing their personalities ... as people they're light-hearted and they're fun and they're sarcastic and we wanted to make sure those aspects of their personality came through in the lyrics," he said.

The song, also produced by Ed Drewett, Wayne Hector and John Ryan, will get its first official radio play on Friday. On Monday, the video will be released. And, the guys have been tantalizing fans with teases for the Hollywood-themed "BSE" video. The latest, which dropped Thursday (July 18), features Harry Styles dolled up as La La Land marketing guru, Marcel.

What do you think is the "best song ever"? Tell us in the comments below!