Natural frequency

The frequency or number of cycles per minute (CPM) or cycles per second (Hz) that a part will oscillate at if it is excited and then left to vibrate at its own speed until it comes to rest. It is dependent on the AV mountings spring stiffness, & hence the AV mountings deflection under load. As a rule of thumb, the greater the mounting deflection, the lower the natural frequency & the better the isolation.