When more than 12,000 people roll into Garner Park Saturday, armed with picnic baskets and an appetite for operatic fare, they'll be sharing in Madison Opera's seventh annual Opera in the Park.

It's an event, to be sure, and a tradition. But at the heart of Opera in the Park is a celebration of the spectacular human voice -- and the musicianship of four singers handpicked for the occasion.

This year they include tenor Bryan Hymel, a rising star on the global stage; young sensation Kendall Gladen, mezzo-soprano; Melody Moore, a multiple award-winning soprano; and critically acclaimed baritone Luis Ledesma.

The four are superb musicians, youthful (all but Ledesma are under age 30, estimates Madison Opera general director Allan Naplan), theatrically skilled, and good looking. And yes, in today 's opera world, when audiences want the full package, all of that counts.

So does diversity -- in racial and ethnic background as well as vocal ability.

"For Opera in the Park, we need tremendous flexibility in their singing, " says Naplan, who with artistic director John DeMain builds the evening 's program around works the singers already have in their repertoire. Saturday 's show will include selections from Madison Opera 's upcoming season, "Madama Butterfly, " "Cosi fan tutte " and "Faust, " then leap into a few operatic hits and numbers from Broadway 's "Ragtime " and "Showboat. "

When casting the free outdoor concert, "It 's always the voice that guides us, rather than anything else, " Naplan says. And yet, although the company 's mainstage productions in 2,000-seat Overture Hall frequently sell out, Opera in the Park offers the opportunity to reach thousands more. The picnickers who flock to Garner Park may be musically open-minded, but they 're not necessarily converts to the operatic art form -- yet.

"The reality is, in an effort to break stereotypes about opera being an elitist, white-bread art form, I think it is especially important for Opera in the Park that it reflect our casting practices, in its full rainbow, " Naplan says. "Historically, we 've always had diverse casting for this event. "

Talent discoveries

Naplan points to baritone Ledesma, born in Mexico, who played Marcello in Madison Opera 's "La Boheme " last year. Ledesma 's mother tongue gives authenticity to the "Granada " he 'll perform in Spanish from Lara 's "Fantasia Espanola. "

"That 's just one example of how repertoire actually benefits greatly from the diversity, " Naplan says.

Both Naplan and DeMain had worked with Ledesma outside Madison Opera, so he was an easy pick for this summer 's performance. Soprano Moore was recruited for Opera in the Park after DeMain heard her sing in Los Angeles; Naplan later saw her in a videotaped production of "La Boheme. " Tenor Hymel came to their attention through his agent; like an increasing number of young opera singers, he also has concert footage on the video web site YouTube.

Technology has changed the way opera companies zero in on talent, says Naplan, but producers also discover singers through the old-fashioned audition process.

In a December ritual, countless professional singers and opera administrators descend upon New York City for auditions, in what amounts to a huge, transcontinental matchmaking session.

That 's how Madison Opera met mezzo-soprano Gladen last winter.

"We thought she was an outstanding artist, " Naplan says. "It just so happened that there was not a role for her (in Madison Opera productions) next season. But she 's a perfect artist for Opera in the Park, and in the future will certainly make it on to our stage. "

Naplan uses a computer database to keep tabs on performers who 've caught his ear, or even those he 's heard a buzz about.

"We 're constantly keeping track of singers, whether it's an established singer or an up-and-coming singer, " he says.

"Certainly we have tried to make a very strong point of bringing in up and coming singers here in Madison. That 's a really exciting thing, when we can get someone who 's right on the rise, " such as marvel Nicole Cabell (seen in 2006 in "The Magic Flute "), Susanna Phillips (in last year 's "La Boheme ") and Stephen Costello (featured in "Rigoletto " in 2006).

"My feeling is that someone who is a diehard opera fan that wants to see the stars can drive 2 hours to Lyric Opera in Chicago, and many of them do, and also attend Madison Opera, " he says. "But what 's exciting about Madison is that you can get the next stars. You can get the people who are singing small roles at Lyric Opera of Chicago, and here can be featured in the principal roles as their careers are developing. "

Passing the hat

Opera in the Park is free to attend, but costs about $200,000 to produce. Volunteers will be passing the hat at this year 's concert for donations.

"We have no revenue source aside from the generous sponsors of the event, " says Naplan, who at this point can 't promise there will be an Opera in the Park in 2009. "Every year, we 're on that edge of, Can we do it this coming year? ' People don 't necessarily understand the vulnerability of it. It 's a huge endeavor every year to attract the funding that 's necessary. "

The upside: After every Opera in the Park, Naplan says, Madison Opera sees a spike in ticket sales for its fall season.

"The reality is that opera used to be a European art form that was not embraced by the masses, " he says. "But as the masses are embracing it, it 's resonating throughout communities that previously were not interested in opera.

"I think the opera business has changed dramatically in its diversity. Conservatories are filling up now with more diverse students. So it 's starting young and bringing up singers, and they 're becoming great professionals. "

IF YOU GO

What: Opera in the Park, produced by Madison Opera.

When: 8 p.m. Saturday

Rain date: Sunday, July 27

Where: Garner Park, corner of Mineral Point and Rosa roads.

Admission: Free. Contributions encouraged.

More information: www.madisonopera.org, 238-8085.