The 108G is very similar to the Bach 1.25G and 1.5G, with a nearly identical cup, when you allow for the Wedge oval shape. The Bach 1.25G and 1.5G have very similar cups, with the main difference in the two mouthpieces being the softer bite radius of the 1.25 rim, which makes it feel bigger.
Material - These mouthpieces can be made in either Delrin or Acrylic plastic. Here is a comparison of their characteristics:
- Feels softer on the chops because it has more give than metal. This is a great advantage for players with braces.
- Not as slippery as silver, giving more grip.
- Added grip makes Delrin mouthpieces feel smaller than their metal counterparts with the same size designation.
- Not as smooth as metal, so some players may feel slight chop irritation for the first day or two while they adjust.
- More comfortable to play in cold weather because they feel warm on the chops.
- Plastic mouthpieces are more responsive than brass, making soft entries more secure.
- Articulation less crisp with less point at the front of the note compared to brass.
- Darker sound than brass.
- Less core in the sound compared to brass.
- Feels softer than brass but less soft and Delrin on the chops.
- Less slippery than metal but more slippery than Delrin.
- Grip intermediate between Delrin and silver.
- Feel slightly smaller than the metal counterparts.
- Smoother than Delrin, very similar to silver.
- Comfortable to play in cold weather.
- Responsive to soft articulation.
- Articulation is clearer than Delrin, very similar to metal.
- Sound is slightly darker than brass and brighter than Delrin.
- More core in the sound than Delrin, but not as much core as metal.
Note: Some bass trombones, for example some vintage King models, have an extra deep receiver. If your mouthpiece inserts more than 1.25 inches (31 mm) into your leadpipe be sure to select the BT Deep Receiver option when ordering bass trombone mouthpieces.