Bruno Tilz 230-A 1 vs Bruno Tilz 231-C 4
The Bruno Tilz 231-C 4 has a wider cup diameter, the Bruno Tilz 231-C 4 features a deeper cup, the Bruno Tilz 231-C 4 has a larger throat opening.
Cup Diameter
The Bruno Tilz 231-C 4 has a cup diameter of 33.00 mm / 1.2992 in compared to 29.00 mm / 1.1417 in on the Bruno Tilz 230-A 1 — a difference of 4.00 mm / 0.1575 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
The Bruno Tilz 231-C 4 has a deep cup while the Bruno Tilz 230-A 1 has a very shallow cup. Deeper cups favor a darker, richer sound; shallower cups provide more brightness and easier upper register.
Throat Diameter
The Bruno Tilz 231-C 4 has a wider throat (8.20 mm / 0.3228 in vs 6.10 mm / 0.2402 in). A wider throat allows more air through, increasing volume and projection but reducing resistance.
Which is better?
Both mouthpieces are categorized as "Catalog" — the physical dimensions above will determine which suits your embouchure and playing style better.