The Milk Carton Kids perform tonight in Utah

Southern California folk duo The Milk Carton Kids have three albums, but the first two were offered as free downloads only.

"It was a big decision for us," said Joey Ryan about selling their songs for the first time.

The new album, "The Ash & Clay," has attracted attention for its throwback sound — a record with instrumentation out of the Dust Bowl, albeit with better sound quality.

The creative relationship between Ryan and his bandmate Kenneth Pattengale has evolved over the years "from fast friends to brothers to a married couple in all the positive and negative ways," he said. "We bicker like an old married couple."

One example is when Ryan, Pattengale and Ryan's wife were in the midst of a long van ride and Ryan and Pattengale engaged in a 45-minute argument about windmills. "My wife was with us and she almost jumped out of the window — and it was a moving vehicle."

For all their arguing, the musicians always remember their roots. "We spent time on the porch learning to play together," Ryan said. "It's the spiritual home of the band."

The Barefoot Movement opens.

When • Monday, 8 p.m.Where • The State Room, 638 S. State St., Salt Lake CityTickets • $15 at thestateroom.com