Videos done by Stephen Birkett using high speed video, showing strings vibrating, dampers, and compression of front felt punchings.
Key compressing a Wurzen felt front key punching00:00:30
Key compressing a standard, woven cloth (partially felted) front key punching00:00:24
Shows the vibration at the bridge with a vertical Wapin pin00:01:29
The damper rises, string vibrates, damper damps string.00:01:29
Viewed at the damper, the strings are seen vibrating (out of phase), then the damper damps them.00:03:39
Vibrations of the string at the bridge pin00:04:04
Showing the propagation of the wave, going back and forth from agraffes to bridge00:01:53
Rising, then lowering and interacting with strings00:01:08