| 摘要 |
A grand piano having a lower lid attached thereto by hinges, and a lid designed for attachment to the bottom of a grand piano. The lid completely covers the bottom of the piano case when latched in a closed position. In its closed position, the lower lid protects the soundboard from damage (such as during transportation of the piano) and mutes the piano's sound. The lower lid of the invention is designed so that, when released from its closed position and pivoted downward into an open position, it will reflect sound from the soundboard outward from the front of the piano. Preferably, the angular orientation of the lower lid in its open position is chosen to reinforce and focus the projection of sound within a desired frequency range (for example, midrange sounds) to a desired target region. Such optimal angular orientation can be determined experimentally. In one embodiment, the lower lid consists of two or more panels connected together by hinges, so that it can be detached from the piano and folded into a compact volume for convenient handling and storage. The dimensions of the lid and the positions of hinges which connect its panels are preferably predetermined so that lid has an optimal orientation for reinforcing projection of midrange sounds (or sounds within another desired frequency range) in a typically-sized room or concert hall when the lid is lowered to an open position in which it rests on the floor.
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