Focus diameter

The sharpness diameter is the diameter of a bell measured at its lower edge, which is called the sharpness . When the diameter of a bell is spoken of, it usually refers to the diameter of the sharpness, as it is usually the largest diameter. In addition to the weight and the course of the wall ( rib ), the sharpness diameter is an important parameter for the pitch of the sound of a bell. When designing a bell, the sharpness diameter increases in inverse proportion to the desired number of vibrations. An octave lower requires roughly doubling the focus diameter.

Examples

The gloriosa of Erfurt Cathedral has a sharpness diameter of 2.56 m and a striking tone of e ⁰ . One octave higher - with a strike note e ¹ - for example, the Marien-Glocke 2 of St. Nicomedes in Borghorst has a sharpness diameter of 1.19 m. Another octave higher with a strike note e ² , the prayer bell of the Old St. Nikolaikirche on the Römerberg in Frankfurt am Main has a sharpness diameter of 0.63 m.

Individual evidence

1. ↑ Fabian Brackhane's Orgelauskunft.de
2. ↑ www.dom-erfurt.de: The Gloriosa in Erfurt Cathedral St. Marien
3. ^ Bells from the collegiate church in Borghorst ( Memento from November 9, 2014 in the Internet Archive )
4. ^ The bells ( memento of November 9, 2014 in the Internet Archive ), St. Paulsgemeinde, Frankfurt