The Philadelphia Orchestra, while awaiting the arrival of its new president, is losing one of its two interim co-presidents.

Matthew Loden will become CEO of the Toronto Symphony Orchestra in mid-July, a few weeks before Matías Tarnopolsky officially arrives to take over as the Philadelphia's new president and CEO. Ryan Fleur, the orchestra's other interim co-president, will fill the brief gap by taking on the title of interim president.

Loden, 50, had been a candidate for the top job in Philadelphia, and said: "I think the time comes when it makes sense to be the number one, to be responsible for everything."

The Toronto Symphony is considered an excellent orchestra, and Loden will be part of the team that selects a successor to Peter Oundjian, who concludes his tenure as music director there at the end of the 2017-18 season. The TSO has been run by interim leadership that took over after the 2016 resignation of previous CEO Jeff Melanson, who was accused of personal and professional improprieties by his (now former) wife, according to the Globe and Mail.

Loden's departure creates one other local ripple in the Philadelphia arts community. His wife, Kristen B. Loden, is senior vice president of advancement at the Curtis Institute of Music, and she will leave that fund-raising position on a timeline yet to be determined, a Curtis spokeswoman said.

Whether the orchestra will replace Matthew Loden has not been decided. Before the exit of Allison Vulgamore as president and CEO at the end of 2017, he and Fleur held vice president titles — Loden overseeing external matters such as fund-raising and marketing, and Fleur managing matters like orchestra personnel, touring, and logistics.

They were both hired in March, 2012, while the Philadelphia Orchestra Association was in bankruptcy.

Tarnopolsky is currently executive and artistic director of Cal Performances at the University of California, Berkeley. Determining the future administrative configuration in Philadelphia will wait until his arrival, Loden said.