An event for the true traditionalists, the “Washington Early Music Festival” will appeal to those who feel classical music lost its way around 1700, when it took a dangerously wild turn with Pachelbel and Bach. Throughout the week, several local ensembles that otherwise might not get a lot of work outside of Renaissance Faires will perform rare pieces from the era before composers discovered tonality, emotion, and fun. Led by violinist Alexandra MacCracken, Ensemble Gaudior will perform chamber music from 17th-century Vienna and Salzburg on period instruments: viola da gamba (a cross between a cello and guitar played with an underhanded bow), harpsichord, and a 350-year-old Stainer violin. Works by Biber, Froberger, Muffat, and Schmelzer highlight the program, which celebrates the musical glory of the Holy Roman Empire. The performance begins at 8 p.m. Thursday, June 25, at St. Mark’s Episcopal Church, 118 3rd St. SE. $20. (202) 543-0053.