Acoustics are the essential
requirement of bell casting. As the basic shape of a Chinese bell,
the ratio of the height to the rim diameter is about l:0.7, while
the ratio is about 1:1 for a Western bell. The Chinese bell
produces deep and melodious notes. The Western bell produces short
and sonorous notes. The strokes of bells contain profound national,
regional and cultural connotations. The Chinese determined the
choice more than 2,000 years ago. Yet we can learn more from the
Yongle Bell. The thicknesses of the bell vary regularly. The waist
of the bell is relatively thin and the lower part of the bell grows
thicker and thicker toward the rim. The varying thicknesses of the
bell make it produce deep and melodious notes and enhance the
harmonization of the timbre.