Materials Used in Trombone Construction
Brass has been the material of choice in brass instrument construction for centuries. While alloys have changed through the years, modern brass is typically an alloy of copper and zinc, with other trace metals present. The exact percentages of copper and zinc in the brass can change the physical color of the metal, as well as its sound, response, articulation, and overall playing attributes.
Yellow brass is the most common alloy of brass used in brass construction. Yellow brass is 70% copper, 30% zinc and typically has a relatively bright sound with a defined outside and stability at higher dynamics.
Gold brass (sometimes called rose brass) is composed of approx. 85% copper and 15% zinc. With its higher copper content, it typically has a warmer, darker sound with a more rounded outside, softer articulation and more change in the color of the sound between soft and loud dynamics. After yellow brass, gold brass is the most common brass alloy used in trombones, and is often seen used in bell construction.
Red brass is composed of approx. 90% copper and 10% zinc. Its playing attributes change even further from gold brass with an even warmer, darker sound, very rounded outside and more substantial changes in sound and response. Due to its relative stability in comparison to red brass, gold brass has overtaken it as a preferred alloy for many builders.
Nickel silver is comprised of brass with the addition of nickel. It is typically lighter and harder than brass and is a very common choice in the braces and ferrules used in connection trombone components together. It is also often used in handslide construction, with either the bottom crook and/or the outer handslide tubes being made from nickel silver instead of brass due to its lighter weight (resulting in a faster slide response) and sound characteristics it can bring to the trombone. Chrome-plated nickel silver is also used exclusively in building the inner handslide.