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Author Topic: Why move the bell not the clapper?  (Read 2899 times)

RKA

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Why move the bell not the clapper?
« on: 22/11/2008 18:18:48 »
Roger Adams asked the Naked Scientists:

Hi - great show guys so keep up the good work!

My question concerns bells, as in belfries of churches and cathedrals. Why do they still, and always have, swung the whole bell to the clapper, rather than just swinging the clapper to the bell.

If you look at the engineering challenge of swinging a multi-ton bell versus a clapper that weighs at most a couple of dozen pounds, it is so much more intricate.

So my question is, is there any scientific or musical advantage in swinging the bell rather than just the clapper.

BTW, I know it must be more fun for the bell ringer to get lifted up by several feet every time the bell does a full swing, but I somehow don't think that's the reason for this weird practice.

What do you think?


 

Offline LeeE

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Why move the bell not the clapper?
« Reply #1 on: 22/11/2008 20:10:32 »
Large bells, as in a belfry, are balanced.  Although their high inertia has to be overcome, this can be done progressively by a relatively weak person, by adding a small amount of energy on each swing.  Unless you could balance the clapper in a similar way, you'd need to put in a large amount of energy for each swing.  In addition to this, the natural swing frequency of large bells is low enough that people can monitor and correct it, keeping it in time, whereas the natural swing frequency of the clapper, in the same size bell would be higher, making it more difficult to use.

Another likely factor is the desire to locate the bells high up so that not only does their sound carry further, it doesn't deafen the campanologists and congregation.  Once you've isolated the bells from the campanologists you need rope to link them and then it's just as intricate, if not more so because the clapper shouldn't remain in contact with the bell after striking, to swing the clappers than just to rotate the entire bell and have the clapper swing free.

I believe that swinging from the bell ropes is seriously frowned upon.
 

lyner

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Why move the bell not the clapper?
« Reply #2 on: 23/11/2008 11:27:55 »
The reason is almost certainly not to do with implementation. They do it that way in many Churches overseas. Hammers against stationary bells are often used in systems which play music and clocks (Big Ben etc)
In church bells, both the bell and the clapper swing freely.
The reason is probably to get the sound 'right'. As the bell moves backwards and forwards it gives a 'chorus' effect as the phase of the note keeps changing. This effect is also very popular when used in the Leslie Speaker, on electronic organs. It is /was  difficult to produce the sound without actual physical rotation. It certainly gives church bells a special sound.
 

blakestyger

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Why move the bell not the clapper?
« Reply #3 on: 23/11/2008 14:45:20 »
The bells in British churches do need that certain sound to be 'right' as sophiecentaur says. I've often thought that village church bells were unusually loud things for such small places but have since realised that they had to be heard all over the parish - an introduction dating from Saxon times.
I remember that about 35 years ago, the bells in the village church where my parents lived packed up because they needed re-bushing. My father, who was handy that way, researched it and did the job for free by turning some new bushes on his lathe and fitting them himself. He used the traditional wood for that job - pear - that had been grown locally. As far as I know they are still working.
I think the Health and Safety lot would have something to say about that nowadays.
 

Offline DoctorBeaver

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Why move the bell not the clapper?
« Reply #4 on: 23/11/2008 15:55:05 »
A lot of churches now use recordings of bells played through load speakers. It sounds awful!
 

lyner

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Why move the bell not the clapper?
« Reply #5 on: 23/11/2008 16:48:40 »
Like an ice cream van!
 

Offline DoctorBeaver

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Why move the bell not the clapper?
« Reply #6 on: 23/11/2008 16:52:56 »
Worse than that. Ice-cream van chimes don't go on for hours!
 

lyner

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Why move the bell not the clapper?
« Reply #7 on: 23/11/2008 17:25:24 »
Plus, I happen to believe in ice cream!
 

blakestyger

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Why move the bell not the clapper?
« Reply #8 on: 23/11/2008 18:54:12 »
Plus, I happen to believe in ice cream!

Very good -  ;D
 

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Why move the bell not the clapper?
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