Perhaps the best indication of how the Backstreet Boys have managed to straddle both their old and new selves on their ninth and latest album DNA is the song Breathe.

The a cappella track is a showcase of their sublime, five-part harmonies that are still as flawless, 23 years since the group debuted.

While it is a callback to the a cappella tracks like I'll Never Break Your Heart, which the boyband kicked off their career with, it is a perfectly up-to-date pop ballad.

That said, DNA is no nostalgic trip and it is clear that the group - made up of AJ McLean, Howie Dorough, Nick Carter, Kevin Richardson and Brian Littrell - are taking chances.

There is also a notable conscious attempt at bringing Backstreet Boys up to date.

Album opener Don't Go Breaking My Heart is filled with bright synthesizers while Nobody Else is layered with lush, electronic production.

The country-pop influences are apparent too, on solid tracks like No Place, Just Like You Like It and Chances, which is bolstered by songwriting credits of One Republic frontman Ryan Tedder and pop star Shawn Mendes.

But there are also the sub-par pop numbers like Is It Just Me and the occasional tacky lyrics ("Who are you? The sex police?) on the likes of New Love.

That said, DNA is a work that does not feel like it is trying too hard to fit into the current pop music sphere.

Instead, it is a natural evolution, befitting of this boyband turned man band.