The sonic differences between ‘Riser’ and Dierks Bentley’s five previous studio albums (excluding ‘Up on the Ridge’) are subtle, but important. The Arizona-raised singer drops the rumbling, rambling, Bakersfield-inspired licks that made up many of his biggest hits and adds great lyrical depth.

‘Riser’ is by far Bentley’s most personal album. ‘I Hold On,’ ‘Damn These Dreams’ and the title track are vulnerable and imperfect, which is in a way, perfect. Melodic choruses don’t always snap neatly into place. At times, his message is left dangling over a more polished arrangement, like a great piece of outsider art at a high end gallery.

‘Here on Earth’ is the best example of this. Sonically, this is the greatest stretch from anything Bentley has done previously. Delicate strings — like a mandolin that needs tightening — play from the right side while a thick bass drives a moody rhythm section. Over and over again on ‘Riser,’ Bentley and producer Ross Copperman create a unique orchestra to back his poems.

That’s truly what the best songs on the album feel like. They’re journal entries read with unmatched passion over an industrial bluegrass sonic palette. One realizes ‘Bourbon in Kentucky’ is a much more powerful heartbreak song than it ever got credit for. Suddenly, Bentley’s experiment works.

A few mainstream, easily digestible cuts like ‘Party Girls’ and ‘Drunk on a Plane’ tip a hat at the rowdy style the 38-year-old singer cut his teeth releasing. But this is an album for fans of ‘Come a Little Closer,’ ‘Every Mile a Memory’ and ‘Home.’ After the upbeat 'Back Porch,' 'Hurt Somebody' bookends 'Riser' with another tormented love song. This singer's many varied influences began forming a unique sound on the 'Home' album. 'Riser' is the next generation.

Key Tracks: 'Bourbon in Kentucky,' 'Here on Earth,' 'Riser'

The Bono: U2 frontman Bono got to hear 'Here on Earth' and really enjoyed it. He thought Bentley should add a more direct religious reference, but ultimately decided that was already implied. Bentley says he should have done it, as then he could say he had a co-write with Bono.

Did You Know?: The road trip Bentley refers to in 'I Hold On' is his move to Nashville. The singer and his dad hopped in the old white pickup truck fans have heard so much about and made the 1700-mile trip. He still drives that truck today.