Now to my take…Trumpets have 3 basic parts. Brass tubing, valves or rotors and a bell. The tubing starts with a tapered piece called the lead pipe or mouth pipe. The taper needs to happen as it is the transition from the mouthpiece to the final tubing size. There is also a variety of venturi openings that begins that taper. The taper can be a variety of shapes and lengths, within a certain parameter, of course. That parameter depends on whether you have a standard tuning or a reversed tuning slide. The mouthpiece receiver and lead pipe determine the blow or resistance that the trumpet has. Those characteristics can feel tight or open and does effect how the trumpet reacts in low, middle and high range. Each maker or brand has certain configurations depending on model of trumpet.
The bore is the final destination of the lead pipe.There are roughly four sizes of bores. Medium, medium large, large and extra large. In numbers that would indicate .450, .459/.460, .463 and .468. Even among these, different makes can be made with a straight bore, (same size throughout) or step bore, ( a gradual increase) as the tubing goes through the trumpet. The valve or rotor section is then sized accordingly. Bore size also influences the feel or resistance and even sound, but some models can have different characteristics depending on the combination of straight bore or step bore. Step bore trumpets can play “bigger” than their bore, especially if the originate as a small bore instrument.
Finally, the bell. Multiple tapers can be had made with different alloys and gauges. The tapers of the bell are the result on the shape they get to the throat of the bell. They can be a fast or a slow taper. Alloys can run from yellow brass to rose or a copper content of brass. Sterling silver also. The thickness of brass is also important. More copper content yields a warmer or darker sound, while the other contents, favor the high overtones. The final touch of the bell rim, be the flat French bead or other, gives one more aspect of the finished sound. Please realize that these descriptions are gross generalizations and that there are many configurations out there that defy being categorized.
Finishes can range from raw brass, lacquer sprayed, silver and gold plating.
How does this apply to your trumpet you ask??? If you have an entry level model, the maker has chosen a tried and true combination that works well with each other. The intermediate models have construction of the entry level with some aspects of the better quality materials. Professional level trumpets have a little more thought and better or different materials put into them. They also are available with more options, depending on what playing characteristics you are looking for. You can find great descriptions in the catalogs of Getzen, Bach, Yamaha, Schilke, and Calicchio. From there, you delve into the realm of the boutique trumpets of Scodwell, Monette, Lawler, Marcinkiewicz, Blackburn, Stomvi, Van Laar, Adams and others.
I hope this has helped, but I also know that it has opened a Pandora’s box of the trumpet world!