Just Hammond: Difference between revisions
| Line 197: | Line 197: | ||
The whole set of frequency ''ratios'' is fixed by the design of the gear mechanism. The driving shaft’s (A) rotational speed ''n<sub>1</sub>'' determines the instrument’s (master-)tuning. Rotating at exactly 1200 rpm (which equals 20 rev./sec), the pitch of note A equals precisely 27.500 Hz or one of its doublings. Therefore the instrument aligns note A with a concert pitch of 440.0 Hz. | The whole set of frequency ''ratios'' is fixed by the design of the gear mechanism. The driving shaft’s (A) rotational speed ''n<sub>1</sub>'' determines the instrument’s (master-)tuning. Rotating at exactly 1200 rpm (which equals 20 rev./sec), the pitch of note A equals precisely 27.500 Hz or one of its doublings. Therefore the instrument aligns note A with a concert pitch of 440.0 Hz. | ||
<math>f_A=20.0/\textup{sec}\cdot\frac{88}{64}\cdot(2^4)=440.0/\textup{sec} = 440.0 | <math>f_A=20.0/\textup{sec}\cdot\frac{88}{64}\cdot(2^4)=440.0/\textup{sec} = 440.0 Hz</math> | ||
[...WILL BE CONTINUED] | [...WILL BE CONTINUED] | ||