John Parduba started making custom mouthpieces in 1915 then opened his original shop in NYC. In the early 30 s Parduba moved to his new shop at 140 W 49th St. where in 1935 he introduced a remarkable new design in mouthpieces for brass instruments. This was the world famous Double-Cup which was unknown and not too popular until 1938 when Harry James discovered it while playing with the Benny Goodman Band across the street from Parduba s place at the Plymouth Hotel. As a result the Parduba Double-Cup became an overnight success throughout the country with trumpet players in many top bands. Name players such as Ziggy Elman and Ray Anthony started using the Parduba and in 1943 Louis Armstrong joined the club. The entire trumpet sections of several name bands were using these fine mouthpieces. Because of the success of his mouthpieces Parduba discontinued making trumpets and cornets and doing repair work and specialized only in making mouthpieces. Today by all standards the Parduba Mouthpiece is still one of the best and most popular. The unusual patented design of the Parduba Double-Cup mouthpiece enables a great ease of playing in the high register. This is noticeable the very first time that one tries this mouthpiece. Although the cup appears to be very shallow the lower half of the cup gives great length to the overall shape of this Double-Cup design which in turn produces a very brilliant yet rich melodic tone. Parduba Trombone Mouthpiece 2. Cup Size 2 Cup Depth 22.12 Cup Diameter 23.30.