Investigation into the strike pitch and partial frequencies of hemispherical bells, including a detailed analysis of modes of vibration, and pitch shift due to variation in thickness. […]
Category: How bells make their sound
Identifying Bell Partials
Description of a simple experimental procedure for identifying the nodal patterns of bell partials. […]
Tubular bells
Determining the strike pitch of tubular bells. […]
The strike note of bells
This article was first published in ‘The Ringing World’ of June 20, 2003, page 586. What determines the pitch of a bell – the note we assign it – has been one of the continuing puzzles of campanology. It was Lord Rayleigh in 1890 who first established scientifically that the pitch of a bell was about an […]
The various ways bells are used
There are various ways that church bells can be used, and this can affect the way they are tuned. The three ways considered in this section of the paper are: sounding singly playing as part of a carillon ringing in changes English style. The last is of most interest, but the first two are briefly […]
Doublets or warble in bells
Bells may not be symmetrical about their vertical axis. This gives rise to the phenomenon of doublets. A doublet is a mode of vibration which sounds at two (usually closely spaced) frequencies rather than one. The easiest demonstration of this uses only a mug and a teaspoon. A mug is not symmetrical – it has […]
The musical pitch of bells
Bells are musical instruments, and are assigned a note on a musical scale which identifies them, and which is used to judge whether a bell is ‘in tune’ with others in a peal or chime. When asked what (single) note a church bell is sounding, most people pick a note about an octave below the […]
Basic principles of bell tuning
Many references describe the way bells are tuned; the Dave Kelly articles, George Elphick’s book ‘The Craft of The Bell Founder’, and Lehr’s paper. A quick recap will be useful. The theoretical background is given in the set of papers Rossing’s Acoustics of Bells. A vibrating bell produces many frequencies of sound, each produced by a different vibrational mode […]
How bells make their sound
This series of articles was written 20 years ago, before I started my PhD research. I have done minor updates to correct mistakes and mis-understandings on my part. These papers touch on issues that are explored in much more detail in my thesis. If you are looking for an introduction to bell acoustics with less […]
Introduction
How bells make their sound is a complex but interesting subject. The discussion here is restricted to bells of typical ‘western’ profile, rather than those of the east which have a very different shape. Western bells are usually hit by an iron clapper at a point on the inside, near the bottom, or by an […]