Abstract: A sound reproduction system (10) is disclosed in which a sound barrier (14) defines a horn passageway having an upstream (22) and a downstream section (24). A driver (12) is mounted at the throat (16) of the upstream section (22) so that its rearward directed output communicates with the downstream section (24). Output from the upstream section and the rearward directed output of the driver are merged at a tap point located at the beginning of the downstream section. By altering the respective areas and lengths of the upstream and downstream sections a variety of different frequency dependent responses are obtained. In one example, low-frequency response systems of heretofore unobtainable compact size are realized.

Abstract: The invention relates to a method for the operation of a pipe organ, with at least one of the valves being provided as a valve actuated in multiple ways which can be controlled to open at least on the basis of two different note demands. In accordance with the invention, on a note demand on a valve actuated in multiple ways which is already open due to another note demand, the valve actuated in multiple ways is closed for an interruption time period and then opened again. The invention further relates to a method for the operation of a pipe organ, wherein information input at the console is transmitted via a data bus to remote receiver units which are connected to valves and/or stop pallets for their control, with the receiver units determining individually from the information transmitted whether, and if so, which of the valves and/or stop pallets connected to the respective receiver unit are to be opened or closed.

Abstract: An addressable valve system is described wherein a plurality of valves are embedded into a single, compact valve block. Each valve comprises a piston moving in a bore in the block. A magnet embedded in the piston is positioned within a coil. When energized, the coil attracts the magnet and the plunger upwards away from a valve seat. Magnetic shields disposed between the pistons provide magnetic isolation between the pistons and simultaneously apply a closing force to the pistons by drawing the magnets downward towards the valve seat. When energized, the coils overwhelm the closing force and open the valves. Electronics for the valve block and the coils are provided on a circuit board overlying the pistons and bores. The electronics provide addressability of the valves and automatically generate “pick” and “hold” timing whereby the initial motivating force (voltage) applied to the current is higher to get the valves moving quickly when valve is first commanded to open.

Abstract: A key-pad operating mechanism of the saxophone for forcibly separating a normally closed key-pad from the tone hole seat via an arm using the leverage principle by pressing the operating lever for the normally closed key-pad even if the normally closed key-pad is stuck to the tone hole seat. The mechanism can easily open the normally closed key-pad without affecting any traditional maneuverability of the instrument and prevents key-pads from becoming inoperable during a play.