Trumpet vs. Cornet

Trumpets are ubiquitous in symphony orchestras, marching bands, jazz groups,
etc. In a standard brass quintet, the lead voice and the second voice are trumpets.

The standard size is the B-flat trumpet. Piccolo trumpets are smaller and so play higher pitches.
They are fairly rare. Bass trumpets are larger and so play lower pitches. They are more rare.

Here are two different models. The obvious difference is the color. They are both made of brass, but one
is plated with silver. The silver trumpet is considered to produce a more brilliant sound, but I believe the
average listener will detect more distinction between the sound of two players than that of two metals.*

Now compare these two. The obvious difference is the overall length. However, they are
technically two different instruments. The one on the right is actually a cornet, not a trumpet.

The cornet has a slightly more mellow sound (although again it's probably not noticeable to the average
listener*). Notice that the tubing on the cornet has a larger diameter on the curve shown below. That's
because it's conically bored—its outward taper begins much sooner than the cylinderically bored trumpet.

Here are two cornets. The noticeable difference between them is the route taken by the tubing.

~ FURTHER READING ~

*I could be wrong; I haven't tested this.