Like much of Africa, Ghana is in the midst of a youth boom, which means that more than half its population is under 25. This is one reason for the country’s bustling music scene, which at one extreme is as glossy and corporate as the west can be. As their name suggests, Alostmen are from the grittier end of things. “We were lost in the street, the forgotten people,” explains Stevo Atambire, the quartet’s charismatic leader and master of the kologo, the two-stringed lute particular to the Frafra people of Ghana’s north. Atambire plays the kologo differently, as a power instrument, and sports a mean, homemade oil-can version. This debut album, much of it recorded in tour hotel rooms by producer Wanlov the Kubolor, has Atambire chopping out trancey rhythms overlaid by strident calls, female choruses and raps by a cool roster of pals. Along the way there are traditional moments, with rattling percussion and one-string fiddle. Teach Me is a rowdy celebration with Nigerian guest star Villy (of Villy and the Xtreme Volumes); hot rapper Yaa Pono shows his style on Fauziah; and on Do Good, another wordsmith, Medikal, preaches stylishly. Hot stuff.