The 56-year-old guitarist Duff McKagan, best known as the bassist of the American hard rock band Guns N’ Roses, which formed in 1985, has just sent a new photo through his social media account and showed his fans the rare thing he does.

He did a tech talk with his fans and taught them something they don’t know.

“Tech talk: I rarely do this, but in the last few days, I’ve been asked a ton about my bass tone on the new Ozzy record. This will be a two part answer, as I use two amps.

“These are the settings I use (zoom in) on the right (gain) side of the Fender Super Bassman,” he added. “I pull out the bass knob for more low end, and Mic up a 10″ speaker on the Fender 4×10 cab.”

While he talks about part two, he showed the blend he used at all live Guns N’ Roses shows.

“Tech talk #2: I also use the GK MB 800 head with these settings (zoom in), and Mic a GK 15′ speaker. I use this blend at all live GNR shows, and on the Ozzy record. It’s a real good mixture of clean and dirty, and has the right amounts of low and high end. If you get it right, it should feel like you’ve been punched in the gut.”

After his twelve years career in Guns N’ Roses between 1985-1997, he rejoined the band in 2016 following the band’s induction into the Rock and Roll Hall of Fame.