The gift was made by DSO board chairman Jim Nicholson and two anonymous donors. The three will match donations made over the next two years.
The grant, the largest ever given to the DSO for operating expenses, is intended to help the orchestra expand its pool of donors and end its chronic deficits. The DSO posted a small surplus this year, but still has an accumulated debut of $2.2 million.
"We are now serving a wider, more diverse community, in many new ways," executive director Ann Parsons said in a statement. "A stable future depends on broad support, finding new donors, and the next generation of donors. "