The vibrations were made by speaking into the large end of a megaphone whose small end was a thin diaphragm that could freely vibrate.

Once the end of their fretboards were elevated above the top of the instrument's face, the entire top could vibrate freely.

Free vibration occurs when vibration is set off with a push and allowed to vibrate freely.

The finely tuned soundboard is left to vibrate freely as no hardware other than bridge posts come into contact with it.

Free vibration occurs when a mechanical system is set off with an initial input and then allowed to vibrate freely.

But none of those solutions addressed the loss of the bass sound, something for which a freely vibrating stage floor is crucial.

Thus, providing the best possible action requires that the guitar fingerboard have a slight curve to allow the strings to vibrate freely.

The middle ear chamber is also large, probably to allow the drum to vibrate freely.

The ligature must allow the reed to vibrate freely without stifling its vibrations.

On the boss with the stringed part of the mallet, and immediately released to let it vibrate freely.