As Willie Nelson has proven, if you’re going to play outlaw country on an acoustic guitar, you really need to deliver the goods and own your songs. On their 2012 debut album, Science of Flight, the El Paso quartet known as The Dirty River Boys play like they were born with this knowledge. The opening cut, “Dried Up,” resonates with a tense contrast of restraint in the verses and propulsion in the chorus so explosive that even singer Nino Cooper’s acoustic strumming sounds tougher than the background electric guitar of Marco Gutierrez. But it’s the desperation and anguish in Cooper’s nasal tenor that makes this tune so riveting. The following “Road Song” swaps out hamfisted strumming for nimble fingerpicking that’s strengthened by a hard-galloping rhythm. The bass work by Colton James is so aggressively played that you can hear his strings rattling against the instrument’s body. The sinister-sounding “Lungs” harks back to late-'90s alt-country, but with an unaffected Red Dirt drawl and a haunting banjo performance that could only come from the western tip of Texas.