The Mountain Goats, like a fine wine, just get better with age. In their 14th album, “Transcendental Youth,” the indie folk band delivers jazzy instrumentals coupled with poetic storytelling. Though “Amy aka the Spent Gladiator”energetically opens the album with declarative vocals and enthusiastic guitar strumming, the rest of the album resonates with a more subdued mood. Darnielle’s voice plaintively narrates contemplative soliloquies and snapshots of longing to quiet minimalist melodies. Standout songs “White Cedar” and “In Memory of Satan” swell with poignant solitude and Sinatra-esque trumpet blares, perfectly marrying understated sounds with quixotic verse. With “Transcendental Youth,” The Mountain Goats prove that some bands really do get better with age.