What Are Period Instruments?From the 16th to the 18th centuries, along with the prosperity of instrumental music, many new instruments appeared and a considerable amount of music was written for them. By the end of the 18th century, however, due to major changes in the various environments surrounding music (the capacity and the acoustics of larger concert halls, the tastes of the audience, compositional styles, etc), some of them were modified and others fell into obsolescence. Accordingly, we call the instruments in the old style "Period Instruments" to distinguish them from "Modern Instruments".
Violins, cellos and instruments in that family share a common basic structure, but there exist important differences that set apart baroque instruments from their modern-day counterparts: gut strings, lighter and convex bows, and a baroque tuning - lower in pitch - that applies less pressure on the instrument confer them a delicate tone and nuanced resonance.
Until the 18th century all woodwind instruments were literally wood, having only a few keys if any, and keyboard instruments like the harpsichord, for which considerable repertoire exists, were plucked and did not initially have pedals. In performance, keyboard players would rely on expressive devices such as tempo rubato, broken chords and improvisation on figured bass-lines.