Thomastik Dominant Pro Series violin strings are designed to enhance the classical sound of Dominant strings. Dominant Pro strings present the skilled violinist with a broad range of sound colors while also providing a balance of brilliance of warmth. Featuring a bell-like tonal character, easily shaped dynamics and excellent projection, these violin strings are great for soloists as well as ensembles. This special Dominant Pro Set contains both an aluminum and silver D string. The silver D which is standard in the Dominant Pro set offers a refined bow noise with brilliance and excellent modulation capacity. With a pronounced sound color, the silver D alloy is more responsive to the bow and does a better job with suppressing wolf tones. The bonus aluminum D is a preferred choice if your instrument requires more brilliance and projection capacity. The aluminum would strings offer more response to the bow compared to silver wound strings. The aluminum D is also a slightly larger diameter, which is some players prefer the feel of a thicker string.