As anticipated, the Foo Fighters are going acoustic this summer with a string of theater dates in July and August.

The quartet has drafted violinist Petra Haden, Wallflowers keyboardist Rami Jaffee, percussionist Drew Hester and former Foo Fighters guitarist Pat Smear to join the all-acoustic tour, which will begin July 11 at the Paramount Theater in Seattle. This will be the first tour that the group will perform songs from disc two of its latest release, "In Your Honor" (RCA).

Tickets go on sale Friday (May 19) for the first seven confirmed dates. Timmy Curran will be opening in July, while Frank Black supports in August. More dates are expected.

The acoustic tour will follow the Foos' biggest career headlining show, which will take place June 17 in London's Hyde Park, for which all 85,000 tickets have sold out.

Here are the confirmed Foo Fighters acoustic dates:

July 11: Seattle (Paramount Theater)
July 13: Berkeley, Calif. (Berkeley Community Theater)
July 17: San Diego (Civic Theater)
Aug. 16: Philadelphia (Tower Theater)
Aug. 21: New York (Beacon Theater)
Aug. 22: Boston (Wang Theater)
Aug. 25: Chicago (Auditorium Theater)