Schilke Symphony M Series Trombone MouthpieceSchilke Symphony series trombone mouthpieces. The M5. 1, M5. 2 and M5. 3 have medium shallow cups for players desiring more brilliance and projection. The D5. 1, D5. 2 and D5. 3 mouthpieces have deeper cups, providing increased depth of sound. The * models have a more tapered throat which will feel more open and will have increased flexibility. The 6. 0 models are improvements on the standard model 60 bass trombone mouthpieces. Call if you don't see