A vibration damper includes a hub, a first mass, a first resilient coupling, a second mass, and a second resilient coupling. The first mass is disposed concentrically about the hub. The first resilient coupling resiliently couples the first mass to the hub. The first resilient coupling has a first spring constant. The second mass is disposed concentrically about the first mass. The second resilient coupling resiliently couples the second mass directly to the first mass. The second resilient coupling has a second spring constant that is less than the first spring constant. The first mass and the first resilient coupling are configured to attenuate vibration at a first frequency. The second mass and the second resilient coupling are configured to attenuate vibration at a second frequency. The second frequency is lower than the first frequency.
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