Pair of tuning forks on resonance boxes

The instrument maker Rudolph Koenig made a vast number of tuning forks with great tonal purity. The identical tuning forks presented here both carry his signature ‘RK’ and the inscription ‘UT3 512 VS’. The latter means that the touched fork produces a note of 512 cycles per second (measured at 20 oC). These tuning forks are accompanied by a resonance box designed in such a way that the air in the box vibrates simultaneously with the tone of the tuning fork. When two resonance boxes with identical tuning forks are placed with their openings towards each other, the vibrations of one resonance box are transmitted to the other resonance box. This phenomenon is called ‘resonance’. This phenomenon can be repeated several times by damping the tuning forks alternately by hand.