Big Star Tuning Fork Rydel Seiffer Graduated

The original design Rydel Seiffer 64/128 Hz graduated tuning fork. End weights convert the tuning fork from 128 to 64 Hz. The weights have been scaled allowing reliable quantitative vibratory testing. As the intensity of the vibration starts to diminish the two triangles move closer together again and their point of intersection moves slowly upwards. The intensity at which the patient no longer detects the vibration is read as the number adjacent to the intersection of the triangles.

Manufactured in Germany to the original specification for over 90 yrs. Each tuning fork check for accuracy.