At least two french horns, four trombones, four trumpets, and two tubas.
A full-size orchestra consists of about one hundred musicians, who play instruments in the string, brass, woodwind, and percussion sections. There are also chamber orchestras, which are smaller and consist of fifty musicians or fewer.
A full orchestra consists of many types of instruments. Scores of music for a full orchestra would include parts for strings, woodwinds, brass, and percussion instruments.
An orchestra is made up of several families of instruments: strings, woodwinds, brass and percussion. Examples of string instruments are violins, violas and cellos. Some woodwind instruments are clarinets, flutes and oboes. The percussion family includes cymbals, timpani, snare drums, and many other instruments.
Because it is a brass instrument...? Many instruments are made of brass.
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The tuba is the biggest brass instrument used in a symphony orchestra. (There are some very rare special pieces of music where a composer might call for an instrument that is not normally in an orchestra. For example, there is a family of brass instruments called ophicleides that were used in the 1800's, and those came in many sizes, including ones as big as the tuba.)
There are many different types of instruments: strings, woodwinds, brass, percussion, etc. However there are variations of those, so please specify if this would be marching band, rock band, concert band, orchestra, etc.StringsPercussionBrassWind
Over the past couple hundred years, the orchestra added more winds and brass. As such, more strings were needed for everything to be in balance.
The trumpet and tuba have 3 keys but not 3 notes. Brass instruments have many notes.
Four.
It varies. Ever hear the term "12 piece orchestra"? That's an orchestra with 12 players.
This orchestra, and most, if not all, others use pretty much the same compliment of instruments from all four families: strings, woodwinds, brass and percussion. What determines which instruments (and how many of each) are used in a particular composition is what the composer has specifically called out to be used. Each composer envisions his/her piece with a certain array of instruments, so there is really no "standard" configuration that is generically applied to all composed pieces.