Monette MF III rim vs Yamaha TR-14B4
The Yamaha TR-14B4 has a wider cup diameter, the Monette MF III rim has a larger throat opening.
Cup Diameter
The Yamaha TR-14B4 has a cup diameter of 16.85 mm / 0.6634 in compared to 16.25 mm / 0.6398 in on the Monette MF III rim — a difference of 0.60 mm / 0.0236 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a shallow cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
The Monette MF III rim has a wider throat (3.81 mm / 0.1500 in vs 3.65 mm / 0.1437 in). A wider throat allows more air through, increasing volume and projection but reducing resistance.
Which is better?
Neither mouthpiece clearly dominates the other — the right choice depends on your embouchure, playing style, and the sound you're after. Try both if possible.