The present invention relates to a piano or a grand piano with a resonance board and strings which rest on a sound bridge with two longitudinal faces. Such a sound bridge serves to transmit vibration energy which is output by the strings of the instrument to a resonance board. The invention is based on the realization that, on the one hand, the rigidity of the sound bridge must be maintained at the locations at which it is in contact with the strings and the resonance board. On the other hand, it is advantageous if the mass of the sound bridge is reduced. For this reason, according to the invention it is proposed that the sound bridge have a first cutout and a second cutout, wherein the two cutouts are arranged on the two longitudinal edges of the sound bridge which lie opposite one another.