In Latin music -- the realm of the troubadour, the serenade and the romantic -- few things separate more clearly the men from the boys (or, in this case, the women from the girls) than what an artist can do with just a voice and a guitar.

Last week at the MO Bar + Lounge inside the Mandarin Oriental Hotel in Miami, Spanish songstress Rosana transformed her guitar into an orchestra with her voice as the expressive conductor.

"I never know exactly what I'm going to sing any given night," Rosana told Billboard after the show, where she performed some of her greatest hits -- -songs of love, joy and optimism -- including "Sin Miedo" (Fearless) with guest Sie7e, the Puerto Rican singer/songwriter also signed to label Warner Music.

The intimate show is part of Warner Music Latino's partnership with Mandarin Hotels that earlier this year also brought Chilean rockers La Ley to the hotel lounge. While that show was fully plugged, Rosana's was fully acoustic.

The Spanish singer took the makeshift stage in front of some 200 people and sat on a comfy couch designed to look like a familiar living room, singing solo for nearly an hour before bringing Sie7e up for their upbeat duet. She ended her show like she ends all her performances: taking her mike and singing a cappella as she walked among audience members.

Not many acts can pull this sort of thing off. For Rosana, who's been relentlessly touring Spain and Latin America with her band, the easy banter goes hand in hand with her potent voice and rousing songs.

That she managed to make it sound new and wonderful -- yet again -- is a testament to the artistry.