The foundation of offshore wind farm turbines using driven piles causes high levels of underwater sound emission during construction. The emitted sound levels are potentially harmful to marine mammals and other sea life. In order to protect the marine fauna, several countries have defined limitations for the sound pressure levels. Therefore, pile driving of state-of-the-art piles for o shore wind farms requires the application of noise mitigation systems, e.g. bubble curtains, to assure that sound pressure levels do not exceed o cial limits. Rapidly increasing dimensions of wind turbines with even higher pile diameters demand additional measures to comply with the o cial regulations. Therefore, the design of the hammer regarding its acoustic characteristics has recently gained attention. Within this contribution, the driven pile as noise source and possible modifications of the pile excitation, i.e., the hammer impulse, to reduce sound emission, are discussed and first results towards a more silent hammer are presented.