The term "classical music" has two meanings: the broader meaning includes all Western art music from the Medieval era to the 2000s, and the specific meaning refers to the art music from the 1750s to the early 1830s—the era of Mozart and Haydn. This section is about the more specific meaning. Classical era musicians continued to use many of instruments from the Baroque era, such as the cello, contrabass, recorder, trombone, timpani, fortepiano (the precursor to the modern piano ) and organ. While some Baroque instruments fell into disuse (., the theorbo and rackett), many Baroque instruments were changed into the versions that are still in use today, such as the Baroque violin (which became the violin ), the Baroque oboe (which became the oboe ) and the Baroque trumpet, which transitioned to the regular valved trumpet. During the Classical era, the stringed instruments used in orchestra and chamber music such as string quartets were standardized as the four instruments which form the string section of the orchestra : the violin, viola, cello and double bass. Baroque-era stringed instruments such as fretted, bowed viols were phased out. Woodwinds included the basset clarinet , basset horn , clarinette d'amour , the Classical clarinet , the chalumeau , the flute, oboe and bassoon. Keyboard instruments included the clavichord and the fortepiano . While the harpsichord was still used in basso continuo accompaniment in the 1750s and 1760s, it fell out of use in the end of the century. Brass instruments included the buccin , the ophicleide (a replacement for the bass serpent , which was the precursor of the tuba ) and the natural horn .
The music of the Classical era is characterized by objectivity. While emotion is an important aspect of all music, in the Classical period, emotions were carefully controlled. This control is evident in the use of dynamics and expressive differences within sections or movements of a composition. The Baroque notion of terraced dynamics, coupled with the expression of a single emotion in a given section of a composition, was replaced by the classical trait of varying the emotional content of a given movement, section, or even a measure of a piece. Dynamically speaking, this was accomplished through the use of crescendo and decrescendo.