The shape of the bell and its tone

Harmonic sets

The biggest influence on a bell’s sound is

- the shape obtained by means of forming using the original template, the so-called rib

- type of materials used: the most pleasant sound is achieved with a copper and tin alloy is used in a ratio of approx. 4: 1.

 

It is said that the bell sounds good if "the sound is harmonized with the bell" - i.e. the strongest tone is consistent with the impact note, then the sound is purest and brightest. The result of many years of searching culminated in the optimal bell pattern designed by our craftsmen, adapted to cast each bell size.

Although the bell is cast according to a specific pattern, due to the uniqueness of each cast, it is often necessary to tune it in order to obtain the desired tone of impact and the associated harmonics. For this purpose, a bell is processed in a way in which the metal from some parts of the bell's interior is removed in order to change the harmonic properties.

Bell Foundry, Marek Kawiński

The shape of the bell and its tone

 

The sound coming from the bell is the result of physical phenomena occurring during the work of this powerful musical instrument.

The bell is one of the most complex percussion instruments in terms of vibrations that appear in it after impact. This results in its construction, i.e. a diversified side profile and variable coat thickness.

 

"To understand how the sound arises in the bells, it is necessary to imagine what happens when the heart hits the bell cup, the heart, after hitting the wreath, causes the circle to be deformed into an ellipse, then the bell's spring forces change the shape of the ellipse by changing its axis.

Changes in the bell profile have not only an effect on the frequencies that can be extracted from it, but also on their intensity. Different tones are excited in different parts of the bell, and so: the the fundamental is raised just above the sound bow, the nominal is near the edge, the hum tone is called at the entire height of the bell but the loudest sounds near the edge, the tierce arouses in the lower part of the coat, while the quint is located just above it and reaches up to the crown. By buckling from the inside of the bell at the appropriate heights, you can change the frequency of certain tones, thus improving others. These changes especially affect the resonance properties of bells.

The uniqueness of bells as musical instruments is revealed in their wording. They are not heard as one sound at a given frequency and timbre, but as a chord of two sounds. This phenomenon is so strange that modern science can not explain this phenomenon. "

 

Analysis of the sound of the Tuba Dei bell

Piotr Więcławski

Bell tones

- lower octave (hum)

- fifth (quint)

- third (tierce)

- primate (fundamental)

- impact tone

- upper octave (nominal)

The tone of a bell and its size

TON

weigt

(kg)

diameter

(m)

TON

weight

(kg)

diameter

(m)

TON

weight

(kg)

diameter

(m)

g 5600 2,06 g 700 1,03 g 90 0,51
gis 4640 1,94 gis 580 0,97 gis 80 0,48
a 4000 1,84 a 500 0,92 a 70 0,46
ais(b) 3360 1,74 ais(b) 420 0,87 ais(b) 60 0,43
h 2800 1,66 h 350 0,83 h 50 0,41
c 2400 1,58 c 290 0,79 c 40 0,39
cis 1950 1,46 cis 260 0,73 cis 35 0,37
d 1650 1,4 d 220 0,7 d 30 0,35
dis 1450 1,32 dis 190 0,66 dis 25 0,33
e 1200 1,24 e 150 0,62      
f 970 1,18 f 130 0,59      

 

Bell Foundry, Marek Kawiński