Is it possible Barbra Streisand's voice could actually get better with age?

That seems like an iffy proposition, with 70 around the corner next year and an upper range that can't last forever. Yet she's never sounded more appealing than she does on her 33rd studio album, What Matters Most: Barbra Streisand Sings the Lyrics of Alan and Marilyn Bergman.

The occasional slight rasp in her voice -- we're talking very slight -- makes her sound almost human. The intersection of near-perfection and near-mortal turns out to be a sweet spot.

The new album hasn't been as wildly anticipated among fans as her previous effort, 2009's Love Is the Answer, which had her tackling standards under the direction of producer Diana Krall. For this self-produced followup, she looked solely to her favorite longtime lyricists, the Bergmans, and swore to take on only songs she'd never recorded before.

Since, as she points out in the liner notes, she'd already cut 51 of their tunes, what was left from their catalog is pretty much obscurities, except the opening The Windmills of My Mind. But for those of us who cotton to the idea of Streisand lending her pipes to something unrecognizable, the lack of familiarity is a boon.

From all appearances, Streisand has reached a secure place in her life, so it makes sense that she should devote an entire album to the work of longtime BFFs whose work positively oozes romantic contentedness. After 50 years of blissfully wed co-writing, the Bergmans are so devoted to love as an eternal ideal, they make Sade sound like Sartre. They're practically AARP poster children for keeping passion alive into the 60s and 70s - and beyond (Alan is 85, Marilyn is 81).

As a result, they have a reputation for schmaltz -- and there's a reason why some of the songs here were originally heard as Oscar-bait ballads in forgotten movies Micki and Maude and The Champ and not Kill Bill. But if the Bergmans have a mutually one-track mind when it comes to exalting the power of love, Streisand's faith in them is not altogether misplaced.

You can -- and maybe should -- wince at hearing Streisand sing lines like The moon must surely love us, as it bathes us in its light or Love's the refuge that sees us through. But when, in I'll Never Say Goodbye, she declares When I say always, I mean forever/I trust tomorrow as much as today, you shouldn't let the fact that the song is the theme from The Promise blind you to the simple profundity of that proclamation of faith.

Windmills of My Mind is the standout, and not just because it probably marked the last time the Bergmans indulged in lyrical psychedelia. Streisand sings a good portion of the standard a cappella, in a reading as effective as it is brave, before William Ross' fairly subtle orchestral arrangement adds to the turbine power.

Ross did most of the arranging, and it's terrific work, though hearing the same substantial orchestra on every track might eventually make you long for the approach Streisand and Krall used on the previous album, where orchestral versions were available on one disc and jazz combo arrangements on the other.

Old hand Patrick Williams shows up long enough to contribute jazzier arrangements for the two oldest and peppiest songs on the disc. One, That Face, was originally recorded by Fred Astaire in 1958 and given by Alan to Marilyn as an engagement present. (Streisand recorded a snippet of it in a medley on her 1966 Color Me Barbra album, so her assertion that she'd never cut any of these songs before merits an asterisk.)

The other, Nice 'n' Easy, dates back to Frank Sinatra's same-named 1960 LP. In a smooth move, Streisand starts the tune off like one of the album's dominant orchestral ballads -- taking Hey, baby, what's the hurry? literally -- before adding in horns (including a Chris Botti trumpet solo) and picking up the pace to a trot.

Regardless of whether these are the songs you've been itching to hear her sing, What Matters Most marks another credible entry in the musical renaissance that began a few years ago, and you won't even have to believe her gracefully aging voice isn't butter. It is, still, the odds notwithstanding.