Female performers give a relaxed, charming show, engaging the audience at Royce Hall to sing along.

At first glance, "A Woman's Heart," a program of Irish music at Royce Hall on Thursday, suggested similarities with "Celtic Woman," which was presented at the Greek Theatre a few weeks ago. Both featured female singers performing Irish repertoire. But the comparisons end there.

Where "Celtic Woman" was a slick, neatly wrapped and packaged musical production, "A Woman's Heart," a franchise dating back to a recording released in the '90s, had the laid-back, spontaneous intimacy of an evening with old friends. Each of its four principal performers — singers Mary Black, Maura O'Connell and Cara Dillon, and accordionist Sharon Shannon — brought unique musical characteristics to their individual sets before joining in a hootenanny-like finale.

Newcomer Dillon, opening the evening, sang in a warm, engaging soprano, her dewy youthfulness countered by her attraction to dark- themed songs. A touching reading of "The Emigrants' Farewell" was one, and "There Were Roses" — written and performed with her husband, keyboardist-guitarist Sam Lakeman — was an especially pointed narrative about the Troubles in Northern Ireland.

Shannon's high-spirited instrumental set followed, mixing fast-paced jigs and reels with a few quiet moments and a final tune, "Potholes," driven by an unexpected contemporary rhythmic groove.

The second half of the bill featured veteran singers O'Connell and Black. O'Connell was, as always, buoyant and entertaining, interacting with the audience, tossing in a joke or two between numbers.

But her cheeky persona drifted into the background when she sang, her intense contralto finding the inner stories in songs such as "Trouble in the Fields."

Black has been visible in this country primarily as a Celtic diva. But her performance revealed what Irish fans have long known — that she is a versatile vocalist who brings energizing qualities of pop and jazz to her foundation in traditional music. Songs such as "Spanish Lady" and "Columbus" were transformed by her gorgeous timbre, and her version of Bob Dylan's "Lay Down Your Weary Tune" enticed the capacity crowd to join in the final choruses.

The entire company wound up this engaging evening with Van Morrison's "Crazy Love" and a final, collective rendering of the production's theme song, "A Woman's Heart."