Just three days after it's release, Mac Miller joined NPR Tiny Desk to perform a few personal favorites off his fifth studio album, Swimming. Backed by a live band featuring a pianist, drummer and wavy bass lines led by Thundercat, the Pittsburg-born MC tackled tracks like "Small World," "What's The Use?" and "2009."

"I really wanted to have strings for this song because this one just means a lot to me," he starts before "2009," a song reflective of his life before the release of his breakthrough mixtape K.I.D.S. "We weren't gonna be able to travel with strings so we sent these guys sheet music and this is actually our first time, we just played it together for the first time 20 minutes ago... It's a beautiful thing, man. Music is a beautiful thing."

Luckily, Mac has a niche for one-time takes. In a recent interview with Zane Lowe, Mac revealed that the memorable bass line off "What's The Use?" came by simply accident. When Mac and his producer had put the track to the side, Thundercat offered some inspiration which quickly became the backbone of the track.

"Thundercat came over that night and I was like, wait, could you try a bass line?" Miller told Lowe. "Swear to God, that was the first thing he played, like not even checking the notes or anything. He literally picked up the bass and that was the first thing he naturally did."

As a result, Thundercat will join Mac Miller and J.I.D. on The Swimming Tour this winter. The 26-date trek will hit every major city starting with San Francisco on Oct. 27 and wrap up in Vancouver on Dec. 10.

Cop your tickets now and watch the 17-minute performance below.

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