Final answer:
The brass instrument described is the trumpet, which uses valves to change pitch and has the highest voice among brass instruments. It employs brass alloys in its construction and has shorter tubing compared to lower-pitched brass instruments like the tuba.
Step-by-step explanation:
The brass instrument that has a mouthpiece, valves, crooks, a bell, and is noted for having the highest voice of all brass instruments is the trumpet. The trumpet is part of the brass family, which includes other instruments such as the tuba, trombone, and horn.
Unlike the trombone, which changes pitch with a slide, or a bugle that has a fixed pitch, the trumpet uses valves to alter the length of the air column, changing the pitch of the notes it produces. The design of brass instruments, which are often made using brass alloys, plays a crucial role in how they generate sound.
Players can vary the pitch in addition to using the valves by changing the embouchure, or the way their mouth interacts with the mouthpiece. As a higher-pitched instrument, the trumpet's tubing is comparatively shorter than that of lower-pitched brass instruments like the tuba, whose tubing is coiled into loops to accommodate its length.