Brass balanced composition and proper production temperatures and parameters to avoid long-term failures. The high malleability and workability, relatively good resistance to corrosion, and traditionally attributed acoustic properties of brass, have made it the usual metal of choice for construction of musical instruments whose acoustic resonators consist of long, relatively narrow tubing, often folded or coiled for compactness; silver and its alloys, and even gold, have been used for the same reasons, but brass is the most economical choice. Collectively known as brass instruments, these include the trombone, tuba, trumpet, cornet, baritone horn, euphonium, tenor horn, and French horn, and many
Tuba second harmonic (an octave higher than the fundamental). These alternative resonances are often known as false tones or privileged tones. Adding the six semitones provided by the three valves, these alternative resonances let the instrument play chromatically down to the fundamental of the open bugle (which is a 29 Hz B). The addition of valves below that note can lower the instrument a further six semitones to a 20 Hz E. Thus, even three-valved instruments with good alternative resonances can produce very low sounds in the hands of skilled players; instruments with four valves can play even lower. The lowest