It seems easier to list the artists Willie Nelson hasn’t collaborated with rather than the ones that he has. But though many of the people he’s sung with (Snoop Dogg, Carlos Santana, U2, Sinead O’Connor) are but footnotes in the Great Big Tome of Willie, Merle Haggard and Nelson’s dual works are a book of their own.

Haggard passed away a little over a year ago, but PBS is allowing you to experience the unique musical chemistry that the two men shared in never-before-seen footage. The network shared a clip from the American Epic Sessions documentary series, which premieres Tuesday night, of Nelson and Haggard strumming through Hag’s “The Only Man Wilder Than Me” in front of an original 1920’s electrical recording system.

The novelty of seeing the two old-timers recording on equipment that was obsolete before they were even born isn’t unique to Willie and Hag, either. The sessions, led by Jack White and Fort Worth native and occasional Austinite T Bone Burnett, use the antiquated technology to offer a glimpse of what contemporary recorded music might have sounded like 90 years ago. We’ll stay tuned to see how that technique translates to artists like, say, Nas—but when it comes to Willie Nelson and Merle Haggard, it sounds pretty perfect.