Construction

Date: 2015-10-07; view: 427.

Trumpet valve bypass (depressed)

The trumpet is constructed of brass tubing bent twice into an oblong shape. The trumpet and trombone share a roughly cylindrical bore which results in a bright, loud sound. The bore is actually a complex series of tapers, smaller at the mouthpiece receiver and larger just before the flare of the bell begins; careful design of these tapers is critical to the intonation of the instrument. By comparison, the cornet and flugelhorn have conical bores and produce a more mellow tone. Bore sizes generally range from 0.430 to 0.472 inches and are usually listed as medium, medium large and large from various manufactuers.As with all brass instruments, sound is produced by blowing air through closed lips, producing a "buzzing" sound into the mouthpiece and starting a standing wave vibration in the air column inside the trumpet. The player can select the pitch from a range of overtones or harmonics by changing the lip aperture and tension (known as the embouchure). The mouthpiece has a circular rim which provides a comfortable environment for the lips' vibration. Directly behind the rim is the cup, which channels the air into a much smaller opening (the back bore or shank) which tapers out slightly to match the diameter of the trumpet's lead pipe. The dimensions of these parts of the mouthpiece affect the timbre or quality of sound, the ease of playability, and player comfort. Generally, the wider and deeper the cup, the darker the sound and timbre.Modern trumpets have three (or infrequently four) piston valves, each of which increases the length of tubing when engaged, thereby lowering the pitch. The first valve lowers the instrument's pitch by a whole step (2 semitones), the second valve by a half step (1 semitone), and the third valve by one-and-a-half steps (3 semitones). When a fourth valve is present, as with some piccolo trumpets, it lowers the pitch a perfect fourth (5 semitones). Used singly and in combination these valves make the instrument fully chromatic, i.e., able to play all twelve pitches of classical music.

A trumpet becomes a closed tube when the player presses it to the lips; therefore, the instrument only naturally produces every other overtone of the harmonic series. The shape of the bell is what allows the missing overtones to be heard. Most notes in the series are slightly out of tune and modern trumpets have slide mechanisms built in to compensate.

The pocket trumpet is a compact B♭ trumpet. The bell is usually smaller than a standard trumpet and the tubing is more tightly wound to reduce the instrument size without reducing the total tube length. Its design is not standardized, and the quality of various models varies greatly. It can have a tone quality and projection unique in the trumpet world: a warm sound and a voice-like articulation. Unfortunately, since many pocket trumpet models suffer from poor design as well as cheap and sloppy manufacturing, the intonation, tone color and dynamic range of such instruments are severely hindered. Professional-standard instruments are, however, available. While they are not a substitute for the full-sized instrument, they can be useful in certain contexts.