The 6BS trombone mouthpiece was one of my very first designs. It was only the second mouthpiece that I developed, coming after the original ‘A’ model which became the famous 4AL. It was inspired by the Vincent Bach 6½AL. This mouthpiece dates back to the late 1920’s and was known as the Clarke Large and originated from Ernest Clarke, the trombonist, brother of Herbert Clarke, the most famous American cornetist of the time.
Over the years this model had been gradually reduced in cup volume and therefore sound quality. In 1968, I found an original from about 1930, and had my engineer measure it. The rim of the original was very sharp and not really usable, so this had first to be modified. After several weeks of careful, painstaking working, we slightly altered the curves in the cup and finally evolved the 6BS. This had a better intonation pattern and clearer and richer overtone structure than the Clark Large, as well as a much fuller low register. It has proved to be our best-selling trombone model over the years. It also comes in a large-bore fitting, the 6BL, and has variants for euphonium; the 6BM and 6BY which have slightly larger bores with European and very small Japanese fittings respectively.