23: Large orchestral backbore.
W1: Reproduction of an old Viennese backbore, sonorous sound.
1: Standard bore of the G1-mouthpiece, classical orchestral backbore
2: Round, soft tone, for symphonic use, ideal combination with G2 cup
89: in between backbore nr 2 and nr 3
G: Original form of the backbore No. 2, similar sound and response behavior of No. 2
W2: backbore shape of W1, but narrower, therefore smaller volume, easier to play
L: Guaranteed precision response; Beautiful, centered tone. Similar to Bach 24
P: Universally applicable orchestral backbore, excellent sound
3: Accurate response, brighter, bearing tone.
54: For symphonic use, great sound
4: For young windplayers well suited, for piccolo still too wide
5: Great sound for piccolo, long seele** for good easy feeling in the high register.
6: For wind players who need a deep cup but have little strength
S: Easy to play, without significant loss of quality in sound, standard backbore of the G3 mouthpiece
25: narrow backbore, easy to play, with precise height recommended for Piccolo
N: For trumpets with Perinet system; Good results with piccolo trumpet
7: For jazz and entertainment music. Bright, transparent sound
117: Similar to the legendary drilling of Bach Corp. Mt Vernon # 117. Bright sound
118: Allround drilling for high demands. Lead backbore with range.
9: Extremely narrow stem hole for individualists
** Seele or soul of a mouthpiece, is the cylindrical space in between the throat and the actual backbore. When enlarging the soul, the mouthpiece gets more resistance because of the air that travels slower towards the backbore. When shortening the soul, the resistance gets less and the sound more round.