An orchestra is an ensemble, or group, of musicians who play a variety of instruments, including string, brass, woodwind and percussion. Generally, orchestras with fewer than 50 members are called “chamber orchestras,” while full-size orchestras of 50 to 100 musicians are called “symphony orchestras” or “philharmonic orchestras.”

The number of musicians required typically depends on the piece of music being performed and the size of the performance location.

Each group of instruments has a leader called the “principal.” The principal is responsible for leading the group and playing solos. The principal trombone leads the brass section, while the principal oboe is the leader of the woodwind section.

The violin section is divided into two groups: first violin and second violin. The principal violinist of the first violins is called the “concertmaster.” The concertmaster is the leader of the string section and helps the conductor lead the entire orchestra.

Before the orchestra begins, the concertmaster makes an entrance alone. He or she greets the public and then, along with the principal oboe, leads the orchestra as the musicians tune their instruments and prepare to play as a group.

The conductor is the leader of the orchestra. Each musician in the orchestra is familiar with his or her part of a piece, but a conductor must be familiar with the entire musical selection. He or she becomes a sort of musical traffic director, telling each instrument how fast they should play, when they should enter the musical highway and when to stop.

Of course, a conductor cannot use spoken words to communicate with the musicians over the music. Instead, the conductor communicates with the orchestra by waving a baton and using special hand and arm movements. The musicians understand these movements and adjust their playing based on the conductor’s silent instructions.


6 Join the Discussion

1 Star2 Stars3 Stars4 Stars5 Stars  (10 votes, avg. 4.70 out of 5)
  1. To use a question as both the title and a bullet-point and then answer it with only one brief sentence does injustice to this topic. It would have been really wonderful to hear the difference between an ensemble, chamber orchestra and symphony. I’m disappointed in this one. And it’s so much more than location and piece. Your answers to the other bullet points are nicely done, however.

    • Thanks so much for your comment and for inspiring a future Wonder topic, Anna! We think the differences between an ensemble, chamber orchestra, and symphony would make for an AWESOME Wonder of the Day! Would you mind contacting us at so that we can take advantage of your musical knowledge when we’re creating the new Wonder? Thanks again!

    • That would take a really long time, Tom…there are quite a LOT of Wonders in Wonderopolis! :-)

      Did you know there are fun ways to search all the past Wonders of the Day? You can click on the word “wonder” in the bar at the top of each page in Wonderopolis and search away! If you’re looking for a Wonder about a specific topic, you can enter that topic into the “search” block at the top right of the page. You can also search Wonders by clicking on a Category (found on the right side of the page). There are many Wonders and many ways to search them! :-)

    • Wow, Emory, how great! We bet you’ll do a marvelous job playing the cello with the rest of the band! We wish you lots of luck during your concert– have a great time playing those five songs! :)

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>


  • Wonderopolis on Facebook
  • Wonderopolis on Pinterest
  • Print

Have you ever wondered…

  • What is an orchestra?
  • Why do orchestras need so many people?
  • What types of instruments do musicians play in an orchestra?

Wonder Gallery

Wonder #69- Orchestra Static ImageVimeo Video

Try It Out

Maracas are a percussion instrument native to the Caribbean and Latin America. Traditionally, maracas were made from gourds or coconuts with dry beans. Maracas are played by shaking them to the beat of the music.

Want to join in the rhythm? You can make your very own maracas using everyday items from around the house. Before you know it, you’ll be an expert at shaking it, too!


Still Wondering

Ready for an encore? Use baseball to explore the instruments and history of the orchestra with the Perfect Pitch interactive activity from ArtsEdge!


Wonder Categories/Tags

Wonder What’s Next?

Music speaks in notes, not words, but it can say so much. Tomorrow we’ll travel to Japan to discover a form of poetry that can say a lot in only a few words.

Upload a Photo or Paste the URL of a YouTube or SchoolTube Video.