Rod Hodges walked into the Music Shed in mid-August to cut tracks for Loose Cattle’s Christmas album, Seasonal Affective Disorder, and a muggy New Orleans summer day suddenly transformed into something completely different.

“It was kinda weird,” said the Iguanas guitarist. “I had just gotten back from California and it was all dark in the studio. I plug in and suddenly I’m playing on ‘The Day It Snows On Christmas.’ It was... psychedelic.”

Hodges was one of several New Orleans mu...