as its inventor, Adolphe Sax, had intended, and that the gradual change to narrower and "brighter" sounding mouthpieces was a distortion of Sax's tonal concept. His students and other disciples felt that the desirable tone for a classical saxophone was a softer, rounder sound—a sound that can only be produced by a mouthpiece with a large, rounded interior (often referred to as an "excavated chamber"). By 1970, narrow-chambered mouthpieces had become nearly universally popular for playing in an environment with amplified instruments, and virtually all new designs featured a narrow chamber, high baffle, or both. Large-chambered and low-baffle pieces continue to be produced for those who seek the tonalities of classical music and "classic jazz." In recent years, new design techniques have emerged such as 3D printing, which allows for the creation of custom saxophone mouthpieces. This innovation was the result of research carried out in IRCAM's scientific and acoustic research laboratory thanks to two acousticians, founders of Syos. Materials Clarinet and saxophone mouthpieces have been made out of hard (vulcanized) rubber, brass or other metal, crystal, glass, plastic, and wood. Today, the most common material for professional clarinet and (classical) saxophone mouthpieces is hard rubber. Jazz saxophone mouthpieces are made out of hard rubber, metal, or (rarely) wood. There is some debate over whether the material affects the tone, or whether tone is shaped only by the internal shape and dimensions of the mouthpiece. According to Larry Teal, the mouthpiece material has little, if any, effect on the sound, and the physical dimensions give a mouthpiece its tone colour. Some recent designs by Van Doren, Bari, and Saxgourmet reflect the theory that the mass of metal over the shank of the mouthpiece, which contacts the neck cork, stabilizes the connection and enhances the integrity of the harmonic series. Capped double-reed instruments On a capped double-reed instrument the function of the mouthpiece is simply to provide a chamber within which the reed can vibrate, with a hole through which air can be blown. Fipple flutes On a fipple flute the mouthpiece, or fipple, provides a shaped passageway for air to be blown against an edge, producing turbulent flow which excites the resonant vibrational modes of the air column. Pirouettes A pirouette is a wooden mouthpiece assembly or lip rest used in some European double-reed instruments, including the piffero, shawm and rackett. In band shawms, it is carried on the staple