The rock world has been shaken to its core this year and one of the most impactful blows was the exit from the stage for Brian Johnson in AC/DC. The singer was forced off the road due to mounting hearing issues and replaced by the capable Guns N' Roses frontman Axl Rose, leaving fans to wonder if he would ever reclaim his iconic roll in one of the world's biggest bands. For now, Johnson has kept busy with life outside of AC/DC, continuing his musical ventures in a collaborative effort with the Greg Billings Band.

The song "Old Friends Don't Come Easy" (video above) is a far cry from the ironclad rock 'n' roll of AC/DC, dialing back the intensity in favor of a bluesy, honky-tonk track that rocks steady with a mid-tempo guitar lick, driven by a light piano melody. Johnson makes his way into the song on the second verse, delivering a less fevered yet still unmistakable take.

On the back half of the track, the music appears to wind down and Johnson says, "Let's get a drink, Greg" to which Billings responds, "Not yet, Brian" and counts the band back in for another series of refrains. The song appears on Boom Boom All Night, the latest album from the Greg Billings Band and not only features Johnson's vocal efforts, but Cheap Trick's Robin Zander as well. Place your order for the album here.

There's no timetable as to when or even if Johnson will return to once again front AC/DC, but the singer has pursued a solution to his hearing problems. Facing permanent hearing loss if he continued to perform with AC/DC, the singer stepped down and later met with Stephen Ambrose of Asius Technologies to test new technology that would greatly reduce the effects of the live performance on Johnson's ears, possibly leaving the door open to his eventual return to the stage.

Johnson also hosts The Producers, a radio program where the singer sits down and talks with legendary record producers like Bob Rock (Metallica, Motley Crue), Kevin Shirley (Iron Maiden, Dream Theater) Roy Thomas Baker (Queen, Ozzy Osbourne) and Nick Raskulinecz (Foo Fighters, Deftones).

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