I have developed numerous bell options over the years with the goal of having more than one viable option for every player's preference. Today, most clients typically have 3 to 4 options that will meet their needs. This allows for slight variations in projection, tonal quality and feedback after you've identified the zone of options that fits you specifically.
Choosing a bell is relatively simple and definitely fun. Want more projection? Then a thicker wall is for you. Want to hear sizzle or more sound behind the bell? Then a thin wall will give you more feedback. Just remember that thin wall bells are relatively fragile and less efficient than standard and heavy options.
Let's start with versatile bell options. Being a performer of every genre, I tend to prefer a balance of brightness, darkness, projection and feedback behind the horn. I want the best of all worlds. Versatility is often the name of the game and the most popular bell that fits every style of music is bell 1. I modeled this bell after the Bach 37 with a few minor changes. It plays more in tune than a Bach 37 or Yamaha Xeno, yet blends with these factory horns easily. The overtone series is vibrant, rich, colorful and satisfying much like a great Bach trumpet, but without the inconsistencies.
Other versatile bell options include bells 9, 7, 3, 4, 6 and 10. That's a lot of options so there's something for everyone. Bells 3 and 6 are more broad and slightly darker than bell 1 offering more low and mid partials in the overtone series. Bells 4 and 10 are even more broad leaning toward a darker tone that is usually suitable for all around playing. Bell 9 is a heavy wall version of Bell 1 designed with a slightly tighter bell tail giving this one more sizzle. And Bell 7 is also similar to Bell 1 designed with a larger bell tail and a larger final diameter of 5.4" producing a vibrant overtone series that projects more evenly to the audience.
My personal favorites are bells 7, 8 and 9. Of course, I would like to have one of each, but since I only have three horns, these are my bells. My Summit Midnight has bell 8, which is standard on the Midnight model. My Summit One has bell 7 and the Medusa trumpet has bells 8 and a tighter version of bell 9. For the past several years, I have only had these three trumpets as my personal horns. Maybe when I get ahead on orders I'll build myself a new Summit Two with the new AGR. At least, that's my goal for September.
The Bell diameter determines the projection pattern. Standard bells before WWI were often cornet and flugel bells, many of which ranged in size from 4 inches to over 6 inches. With the big band era came a small bell trend in taper, volume displacement and diameter. Most bells in the the 1920's through the 40's had relatively less volume displacement, tighter tapers and a smaller diameter than their predecessors. This was likely due to the nature of big band music, but I can't be sure as I wasn't born until the 70's.
A smaller bell diameter projects more directionally, which is nice when you want your music to move forward toward the audience like in a rectangular hall. Likewise, using microphones is typically easier with a smaller bell diameter, but you sacrifice tonal color and an even projection pattern in the process.
A larger bell diameter projects more evenly. This is ideal for intimate venues, small audiences, playing softly and being more expressive with your sound. And larger diameter bells work great for larger rooms or even arenas as the sound projects more like the wide setting on an adjustable flashlight. It is unlikely that anyone will get too much light in their eyes with this setting and the same is true musically. A larger diameter bell often results in more listeners sharing positive experiences as they no longer hear the shrillness so common in trumpet projection patterns.
Less bell volume in terms of displacement reduces the amplitude of partials in the overtone series. This means that smaller bells have less richness and are usually interpreted as having more edge. This is due to the physical limitation of the smaller space, which results in the full overtone series being diminished. Smaller bell volume is great for players who have lost some of their hearing or for those who prefer a brilliant tone that is easy to hear. I generally do not produce bells with an extremely small volume, but they are produced by other manufacturers.
More bell volume in terms of displacement increases the amplitude of partials in the overtone series. Yes, this is the opposite of the last paragraph. Larger bell displacement can be measured in the taper or by filling a bell with water, then pouring it into a measuring cup. The largest bell I produce is the 8, which is probably the largest taper available from any manufacturer. This bell produces every partial in the overtone series and it is obvious the first time you hear a Summit Midnight. The tone is so big, vibrant, rich and full that most people wonder if there are other trumpet players in the room playing along. All of the bells I offer have a fair amount of volume to create more of this affect with bells 1 and 9 being the smallest options.
Bell thickness affects projection, feedback, intonation and efficiency. There is a fair amount of physics I could bring into this explanation, but in basic terms a very thin bell will lose energy more easily than a thicker bell. This is due to the anti-nodes setting the bell wall into physical motion. The more your bell vibrates, the more energy you lose and the more problems this will cause. Thin bells are responsible for poor projection, intonation and efficiency. However, a thin bell will give the player a ton of audible feedback behind the horn.
Lead players who insist on playing lightweight bells to project are literally fooling themselves. It is physically impossible to project your sound further with a lightweight bell when compared to a standard or heavyweight option of the same taper, material and diameter. So why do so many lead players use thin bells? Usually because the feedback behind the horn sounds better to the trumpet section! Ask the audience and you will always get a different response as thin bells cannot project across a large room. I have had this conversation with many great players and several of them disagree with my findings. The evidence is overwhelming and you can test this yourself with a decibel meter if you're on a budget or a full spectrum analyzer if you have access to the equipment. Simply place your measuring device at the back of the hall and compare horns. Thin wall bells project less amplitude on most or all partials in almost every test.
I do offer lightweight bell options, but these are recommended only in situations where they are actually needed. The player who has lost a lot of hearing is the most common scenario followed by the lead player who insists they cannot play an efficient setup. The most efficient lightweight option I offer is bell 10GLT, which is relatively broad and stable. But at the end of the day, a standard weight bell will project further, play more in tune and easier. The major drawback to lightweight bells is that they are damaged easily.
Now let's get into the thicker options, bells 5 and 9. Bell 5 is made of pure copper and is the most efficient option I offer. However, it is the least popular bell as most players prefer the extra vibrancy and chaos that is present in the overtone series of a thinner, harder material. Copper is soft and does not set into motion easily meaning it is considerably more efficient than brass. In fact, Aluminum has these same qualities and I will soon be milling bells from solid Aluminum billet for this reason. The drawback to copper is that the tone literally sounds too pure for many players who are accustomed to the sound of a Bach, Schilke, Getzen or Yamaha. Bell 9 is almost the opposite of bell 5. The 9 option is very efficient, vibrant, colorful and it is the thickest brass option I offer.
Which bells are best for Orchestral playing? Well, the answer to this question will depend on the type(s) of orchestra(s) and the region of the world you are performing. Many orchestral works call for a broad, dark, open sounding trumpet while others require bright and light. Ideally, an orchestral musician would have many options at his or her disposal and perhaps more so than any other musician.
My major was in Trumpet Performance with an emphasis on Orchestra at a small private college known for very high standards in classical music studies. It sounds great to pre-qualify my advice to you by stating I went to a really cool school, but in reality what I have discovered is that you do not need a degree in something to be competent or even great at any skill. And my recommendations are general in this blog entry so your ideas of what will fit your playing best may change after we have had a conversation in person, on the phone or after you have tried a specific bell first-hand. People are subjective and choosing a bell is also subject to the circumstances. Also, all bell recommendations are the same for Bb and C trumpets.
With all that said, here are my recommendations for bells listed by composition;
On to Jazz, Lead, Commercial, R&B, New Orleans Traditional Jazz and more. I've played my fair share of gigs in every genre so I do have my specific preferences for various settings. But to give you a general idea of what most of my professional clients choose, here's a list of options listed by genre;
A note on "X" bells, these are turned on the same mandrels as their counterparts with an extra wide diameter, usually 5.3" or larger. The X bells spread your sound out more evenly to your audience for a more consistent and enjoyable listener experience.