Unknown Mortal Orchestra have been mostly mum in 2016 besides a contribution to the National’s triple-disc Grateful Dead tribute compilation Day Of The Dead and the one-off single “First World Problem.” The trio is back today to continue its holiday-time ambient instrumental series that started in 2013. They’ve already shared three 20-minute-plus excursions in as many years with “SB – 01,” “SB – 02,” and “SB – 03,” and today they drop the fourth annual installment, “SB-04.” Just like the others, it’s 20 minutes of warped, winding, ambient psychedelia that keeps the ear guessing. Check it out below.