Vertically and Horizontally Balanced Subwoofer

摘要

A speaker system, particularly useful as a subwoofer, comprises an enclosure with one acoustic transducer facing to the right and one acoustic transducer facing to the left, which effectively cancels out transducer cone mass induced vibration within the enclosure. The enclosure also has one passive radiator facing up and one passive radiator facing down. The passive radiator facing down effectively couples acoustic energy at very low frequencies into the floor. The passive radiators each have a rather a large area and high mass. The large, high mass, bottom mounted passive radiator will produce large amounts of enclosure vibration, and so to cancel this vibration, the upper passive radiator is of substantially the same mass and size. The resulting system will be vibrationally balanced on all axes while simultaneously effectively coupling low frequency energy onto the floor of the listening room with good efficiency.

主权项

1. A loudspeaker system for having a total mass, the loudspeaker system comprising:
a first panel, the first panel defining a first opening, the first opening having a first area; a first opposite panel underneath the first panel and being substantially parallel to the first panel, the first opposite panel defining a first opposite opening, the first opposite opening having a first opposite area, the first area and the first opposite area providing a cumulative passive radiation area; a second panel extending between the first panel and the first opposite panel, the second panel defining a second opening, the second opening having a second area; a second opposite panel extending between the first panel and the first opposite panel, the second opposite panel being substantially parallel to the second panel and being substantially perpendicular to both the first panel and the first opposite panel, the second opposite panel defining a second opposite opening, the second opposite opening having a second opposite area, wherein the second area and the second opposite area provides a cumulative driver radiation area; a third panel extending between the first panel and the first opposite panel, the third panel further extending between the second panel and the second opposite panel; a third opposite panel spaced apart from the third panel, the third opposite panel extending between the first panel and the first opposite panel, the third opposite panel further extending between the second panel and the second opposite panel; an enclosure being comprised of the first panel, the first opposite panel, the second panel, the second opposite panel, the third panel and the third opposite panel; a driver at the second opening of the second panel; an opposite driver at the second opposite opening of the second opposite panel, each of the driver and the opposite driver comprising a magnet voice coil and an active diaphragm with a voice coil, the active diaphragm being driven to move relative to the enclosure in response to an electromagnetic interaction between the magnet and the voice coil, the magnet being substantially fixed relative to the enclosure, the active diaphragm of the driver and the active diaphragm of the opposite driver providing a cumulative active radiator mass; a passive radiator at the first opening of the first panel; and an opposite passive radiator at the first opposite opening of the first opposite panel, each of the passive radiator and the opposite passive radiator comprising a passive diaphragm that is driven pneumatically in reaction to movement of the driver and the opposite driver, the passive diaphragm of the passive radiator and the passive diaphragm of the opposite passive radiator providing a cumulative passive radiator mass, the enclosure having an enclosure mass equal to the total mass of the speaker system minus a combination of both the cumulative active radiator mass and the cumulative passive radiator mass, the driver being substantially equal to the opposite driver, the passive radiator being substantially equal to the opposite passive radiator, and the cumulative passive radiator mass being at least three times greater than the cumulative active radiator mass.