The Wisconsin Chamber Orchestra made beautiful music during its 25th annual Concerts on the Square series this summer. And it's scheduled to begin its new fall season at Capitol Theater in early October.

But behind the scenes, there's discord.

WCO management's contract with its musicians expired Sunday, with both sides wrangling over issues such as who should be covered by the agreement and how much out-of-town musicians should be reimbursed for travel.

Negotiations began in February and a federal mediator was called in this summer, said Todd Jelen, a WCO musician who is helping negotiate on behalf of his fellow orchestra members. The current contract will remain in place while both sides plan for the next round of meetings Sept. 15 and 16, but a strike is not out of the question, Jelen said. The Madison Symphony Orchestra, which begins its season Sept. 26, is a separate organization and not involved.

Along with WCO Executive Director Doug Gerhart and General Manager Martha Scales, the orchestra's board has called in Foley & Lardner labor attorney Daniel Kaplan to negotiate on behalf of management.

"Sometimes the earlier you start doesn't necessarily mean that you reach agreements any sooner," said Gerhart, who joined the process when he became the WCO's top administrator in June.

"We're not going to talk about negotiations in the press," he added. "We just continue to discuss lots of items. And the items, as you could imagine, are anything from work rules to rates of pay."

The last time the WCO's musicians and management negotiated a contract, in 2002, the process took a  year, said Jelen, principal bassoon for the WCO. Jelen shares musician bargaining responsibilities with three other WCO musicians and Brian Whitty, a bass trombonist and board member of the American Federation of Musicians Local 166. A negotiator from AFM's national office also consults.

Although not a WCO member, Whitty regularly performs with the group, and, therefore, is known as an "extra" -- a key term in the current talks.

Only 33 musicians are listed on the WCO's official roster, including 19 string players, eight woodwinds, four brass and two percussion. Additional musicians hired for specific shows, such as the Concerts on the Square series, are "extras."

"So the group you see on the Square most of summer," Whitty said, "including three trombones, one tuba, one harp, two of the four horns, drum set, keyboard, any extra flutes, clarinets, bass clarinets, extra bassoon, extra percussion -- those (additional) musicians are all extras."

The union wants "extras" and "subs," musicians who perform in case of an absence, covered under the same contract as WCO members, so they would receive the same protections and compensation. Contracts prior to the current agreement did cover subs and extras, Jelen said.

"The (core) players feel that they should be part of the contract," he said. "We think we would be doing a disservice to them and to the subs and extras to just drop this."

Extras and subs are paid "roughly half" of what WCO core musicians make, Whitty said. As an extra, he performs in all the WCO's summer shows, as well as the annual Halloween and holiday pops concerts, the "Nutcracker" ballets, "Side by Side" concerts with the Wisconsin Youth Symphony Orchestra and several Masterworks performances, he said.

"We have the same responsibilities of preparation of music and performance excellence that is rewarded with the higher pay rate for a core musician, and is not recognized or rewarded with the extras or the substitutes," Whitty said.

Musicians also want a boost in travel reimbursements. About a third travel from out of state for rehearsals and shows, said Jelen, who lives in Ohio.

So far, the mood of the negotiations has been "relatively respectful," Gerhart said. "You know, I was a musician -- past tense. I understand these issues well. It's always about trying to reach some sort of a happy middle ground, if that's possible, that's (financially) responsible and acknowledges the fine work that people do in the orchestra."

"The sentiments are that we want to wrap this up and bargain collectively to get a contract," Jelen said. "However, we do not know where the law firm and the board stand on these issues. We're prepared for everything, though."