BELL FLARE
Until the second half of the Twentieth Century, most french horns were built with one piece bells with the exception of some
European brands. Certainly the makers knew that different alloys, hardness, and size greatly influenced an instruments
playing characteristics, but the player could only use what the manufacturer provided. In 1960, the Baltimore Symphony horn
section began using screw bells of different alloys. It was found that one horn could be three horns by using three bell flares.
From that beginning, Lawson Brass Instruments began experiments to see what the weight, alloy, hardness of the metal, and
the size of the flare had to do with the way the instrument performed. The bell flares that were used were made by other
manufacturers until Lawson Brass became capable of making their own.
From the early 1970's, Lawson Brass performed numerous tests, first on hardness of the bell flare, then, sponsored by the
International Horn Society, a test to see what effects different bell alloys would have. The Copper Development Association,
a public relations arm of the Copper Industry, provided much data about copper alloys and Lawson Brass Instruments was
fortunate to have the help and advice of Mr. Thomas F. G. FitzMaurice, Metallurgical Engineer of the Anaconda Brass Co.
in Waterbury, CT. who suggested and helped procure different samples of copper alloys for experimentation.
The early bells produced were of the following alloys:
CDA260 - Yellow Brass containing 70% copper, 30% zinc.
CDA230 - Red Brass containing 85% copper, 15% zinc.
CDA752 - Nickel Silver containing 67% copper, 18% nickel, 15% zinc
In 1979 Lawson Brass Instruments introduced an alloy that was originally designed for architectural structures, a strong but workable material that had never been used for musical instruments. It was AMBRONZE. A beautiful, golden, copper alloy.
CDA 425 - Ambronze containing 84% copper, 2% tin, 14% zinc.
A search for the alloy that the famous Kruspe nickel silver horn was made from yielded NICKEL BRONZE, the closest alloy available now to the pre-WWII German nickel silver used by Kruspe.
CDA 725 - Nickel Bronze containing 89% Copper, 2% tin, 9% nickel
At the present time Lawson Brass Instruments produces french horn bells and tails in both Ambronze and Nickel Bronze. By special order, instruments can also be supplied in Yellow Brass (cartridge brass).
Playing Characteristics
1. Shape, size, and thickness - Subtle differences in playing characteristics such as ease of starting notes, dynamic range,
carrying power are influenced by these dimensional properties.
2. Stability - The internal dampening characteristics of the bell flare influence the stability of the pitch, ease of starting the
sound and the ability of the instrument to maintain sound through slurs. Dampening is controlled by alloy, weight and hardness.
3. Dynamic range - For a given alloy, the hardness affects the dynamic range. A softer bell flare distorts at a higher input of
sound so that more control of dynamics is possible. Varying the hardness gives different degrees of brightness or darkness to
the sound.
4. Tone color - The alloy and its' hardness controls the timbre or color of the sound. This color change is most noticeable at
high dynamic levels.
Differences
The Ambronze bell flare has a powerful, wide dynamic range. The color is nearly constant throughout.
The Nickel Bronze bell flare responds quickly (short start-up time), has a powerful, wide dynamic range. The color changes
from dark at low dynamics to bright at high volume.
For a more technical discussion of material design and some frequently asked questions link to our Materials page.