Andy Hackbarth was hailed as a classical-guitar virtuoso in his early twenties; in 2006, he left Colorado for Nashville, where he honed his songwriting skills to catch up with his playing. His last effort, 2010's The Last Love Song, made it clear that Nashville had helped him develop a knack for writing catchy, hook-driven tunes. While he hasn't totally abandoned the pop feel of that album on his new seven-song EP, Treadmill Horses, the songwriting feels more mature and introspective. It's as if he's widened his scope somewhat, reaching deeper than just writing hooks and sprinkling a bit of jazz and country into the mix. "Windmills," a tribute to Pablo Neruda's odes, is a gorgeous effort supported by dual violins, while "1939," inspired by one of America's first paratroopers, is buoyant with harmonies.