ReverbBy Colleen SmithThe Wailin’ Jennys lend new meaning to the phrase “harmonic convergence.” The women (two Canadians and an American) braided their vocals to create perfect chords at the L2 Arts and Culture Center on Friday.I first heard the Jennys on Garrison Keillor’s radio program, “A Prairie Home Companion,” typically broadcasting throwback bands and folkie musicians. Keillor has invited the Jennys back to PHC more than once. He once commented on air that if he ever were to get married again, he’d hire the Jennys to sing at his wedding.The Wailin’ Jennys do sweeten their music with a traditional element of tender romance, but a melancholy bittersweetness prevents any sticky saccharine. At Friday’s sold-out Swallow Hill show, the Jennys heartfelt love songs provided a perfect prelude to Valentine’s Day.The mixed-generation crowd seemed well aware of the Wailin’ Jennys’ music, despite the fact that the sold-out concert was the band’s first ever show in Denver. An attentive audience fell silent during songs, allowing for every nuance of their delicate acoustic tunes.The three songbirds turned in tightly knit harmonies reminiscent of “Trio” — the combination of Emmylou Harris, Linda Rondstadt and Dolly Parton. A rapturous set-list blended one part Appalachia, one part heavenly host, one part Pointer Sisters, one part Indigo Girls.The band did a few covers. “Bring Me Li’l Water Silvy” allowed me to forget for several minutes the fact that we live in the digital age of robots and phones smarter than I.Each of the Jennys writes songs, so they’ve developed a broad catalog of original material. Selections from their brand new release “Bright Morning Stars,” including the title track, “You Are Here” and “Bird Song,” convinced me to buy the fresh CD.Ruth Moody invited audience participation on “Glory Bound,” her “non-denominational Gospel song.” The sing-along succeeded because the Swallow Hill crowd can carry a tune. Moody’s song “One Voice” is, for my money, one of the most hauntingly beautiful and hopeful songs ever recorded. I bought the live CD for these songs.The Jennys also are accomplished instrumentalists. Moody alternates between acoustic guitar, banjo, accordian and bodhran (that funky, handheld Irish drum), and on one number multi-tasked by playing a tambourine with her foot. Heather Masse plucks an upright bass. Nicky Mahta plays acoustic guitar, percussion and ukelele.The Jennys’ act is something of an extended family. Moody’s brother accompanies on fiddle. Mahta’s husband serves as the sound man.To their credit, Swallow Hill anticipated the popularity of the Wailin’ Jennys, booking them at L2, an elegantly cool concert venue. Swallow Hill concerts lean heavily toward amiable, laid-back ambiance; so during the Jennys’ encore, when the three songbirds split their guts laughing on three attempts at an a capella song, nobody minded. The audience laughed along.Aside from an impromptu crack-up, don’t expect any sensationalism or outrageousness: The Jennys don’t need it. They trade not on shenanigans or shock value, but talent.