British singer-songwriter Laura Marling says she compulsively collected records from 1969 before she started working on her fourth album. That probably explains why so much of ‘Once I Was an Eagle’ sounds like Joni Mitchell, whose breakthrough record, ‘Clouds,’ came out that year. From the opening ‘Take the Night Off,’ which segues seamlessly into the title track, Marling’s hushed vocals, gently strummed acoustic guitars and hyper-personal lyrics are ripped from Mitchell’s early-‘70s playbook, before her jazz ambitions got the best of her.

But there’s more to it than that. The 23-year-old Marling’s delicate phrasing recalls Mitchell at her peak ‘Blue’ and ‘Court and Spark’ era, with deep growls easing into soft whispers and then higher-register passages. The spare instrumentation – mostly just Marling on acoustic guitar along with cello accompaniment and the occasional drum brush supplied by producer Ethan Johns – makes it hard to turn away. Unfolding, for the most part, as a single piece of music, ‘Once I Was an Eagle’ demands your attention until it loses it about three-fourths of the way through.

On her first three albums, Marling firmly planted herself in the middle of a British folk revival that includes Mumford and Sons. Her tentative steps have become more steady and certain along the way. ‘I Speak Because I Can,’ her 2010 record, was flush with confidence, stoked by the dynamic backing grooves. ‘Once I Was an Eagle’ is her first stripped-down acoustic album, and she sounds even more poised in the spotlight.

The first part of the album is strung together like a suite, but the best songs on the overlong ‘Once I Was an Eagle’ stand sturdily on their own, like the bluesy, busy 'Master Hunter’ (a dead ringer for the rustic shuffles found on Led Zeppelin’s mostly acoustic third album), the lovely, lilting ‘Where Can I Go?’ and the sprawling ‘Pray for Me.’

Still, Marling is a modern woman with little patience for the occasional naiveté that seeped into Mitchell’s early records. “Damn all those hippies who stomp empty-footed upon all what’s good or what’s pure,” she sings in ‘You Know,’ hoping to distance herself from the comparisons. But placing those words on top of a melodic foundation straight out of ‘Court and Spark’ doesn’t help Marling’s case. She’s a strong songwriter with sizable ambition. She just needs to find her voice and narrow her scope. Then she’ll really have something.