The orchestra in Baroque period was very unstable, depending on the number of musicians employed in each court and the instruments they used. So some bands have a lot of wind music, and some bands have no wind music at all. Only string instrument groups are relatively fixed, usually based on complete violins and violin instruments. Plus bass ensemble.
In the era of Haydn and Mozart, the band began to have a relatively formed norm. Generally about 30 people, including the complete string group. Wind instruments are flexible, and there are few complete wind groups. There is almost no percussion. A few cases use timpani and other percussion instruments.
From Mozart's later years to Beethoven's era, the band gradually expanded to about 50 people. In Beethoven's era, the woodwind group was basically formed, while the brass group was more changeable, and the most stable ones were the horn and trumpet. In Beethoven's time, trombone was first used in bands, while tuba was later. Beethoven's emphasis on timpani promoted the important position of this instrument. Except for the timpani, other percussion instruments are still rarely used.
After Beethoven, Berlioz was regarded as the pioneer of modern big bands. In his time, big bands have grown to 100 or even hundreds of people. There are many percussion instruments, such as triangle iron, gongs, bowls, drums and cymbals.
In the middle and late period of romanticism, with the increasing influence of nationalism in music, many composers began to use non-western traditional percussion instruments to create special effects, and a large number of unconventional percussion instruments, including wooden fish, castanets and tambourines, also poured into modern bands. As the most important symphony composer in the late Romantic period, Mahler added more things to the band that could hardly be called musical instruments. Such as sledgehammers and boards. In order to pursue special effects, opera composers also use birds' songs, whistles, rifles and anvils.
At the beginning of the 20th century, the band was basically fixed at the scale of 100 people, and sometimes it was increased or decreased as needed. As for the number of percussionists, it depends on the selected works. Of course, some domestic orchestras, especially informal orchestras, also passively choose tracks because they can't find enough musicians.