Voice of Ages marks the Chieftains 50th anniversary. Initially, Paddy Moloney wanted to get all the living members of the band together for an album-length jam on “Toss the Feathers.” Concord and co-producer T-Bone Burnett had a different idea. Advance label and press hype crowed about the radical approach of this album because of its collaborations with indie rockers -- nonsense. Given the Chieftains' history, collaboration -- Van Morrison, Emmylou Harris, Sting, Mary Black, Mick Jagger, Mark Knopfler, and Ry Cooder, to name a few -- is an integral part of their mission. Voice of Ages' 15 cuts contain, sadly, only one solo number. "The Chieftains Reunion" is among the album's best moments and clocks in at over 11 minutes, giving Moloney's original notion a nod. Other highlights include "Carolina Rua" with Imelda May (followed by the Chieftains jamming on a reel), "Come All Ye Fair and Tender Ladies" by the Pistol Annies, who wed their unique roots music to the Celtic tradition seamlessly, the stunning, "My Lagan Love" with Lisa Hannigan's otherworldly voice, and the Civil Wars' reverent yet joyful reading of "My Lily Love." On these cuts, one can hear the Chieftains really creating with their intuitive magic; extending the scope of Irish music into the world of popular music, with vocalists who understand -- at root level -- what they're all about. Another winner is Bob Dylan's "When the Ship Comes In" with the Decemberists. While Dylan's tune is based on a traditional Celtic song, the band's performance lends inspiration and celebration to the Chieftains' arrangement. "The Lark in the Clear Air/Olam Punch" and "The Frost Is Over" with the Punch Brothers produce fine results because the approach to the material is loose and lively -- and accommodating. Stephen Foster's "Hard Times Come Again No More," with Paolo Nutini's gentle yet reedy vocals backed by the Chieftains at their mournful best, also features the City of Limerick Pipe Band, who give it a stately finish. Together, they make this parlor ballad as moving a reading as any out there. Some tunes just don't work, though: Bon Iver's reading of Charlie Monroe's wonderful murder ballad "Down in the Willow Garden" is labored, tired, and boring. Given the song's emotional core, it deserves to be treated with something more than faux hipster detachment. The Carolina Chocolate Drops try way too hard on "Pretty Little Girl" -- though the Chieftains sound fantastic. The Low Anthem's version of Ewan MacColl's "School Day's Over" is far too studied and restrained. The bonus track, "Lundu," with Galician piper Carlos Nunez -- and his family members helping out on bouzouki, electric guitar, percussion, and loops -- is rough and ready. It feels like a spontaneous demo, sending Voice of Ages off on a high note as the Chieftains get their Irish reel groove on. Voice of Ages is a good Chieftains recording; its solid performances easily outweigh its duds, but it feels like something less than a 50th anniversary celebration. Moloney's original idea would have been more fitting, and really something to hear.