Piano with sound-enhancing system

In a piano having a main frame, a string-holding frame supported by and inside said main frame and having strings thereon, a keyboard with keys, and a sounding board, the combination therewith of:

• an amplifying assembly, comprising
• pickup means mounted on said sounding board for picking up sound directly from said sounding board supported on said piano,
• amplifier means supported on said piano and connected electrically to said pickup means,
• loud speaker means supported on said piano and electrically connected to said amplifier means, and
• baffle means for preventing feedback from said loudspeaker means to said sounding board,
• said pickup means comprising at least one piezoelectric pickup in a housing that is in direct contact with said sounding board,
• said housing having a front plate and a rear plate spaced apart with said piezoelectric pickup in between them and in electrical contact with one said plate, and insulator means filling the space between said piezoelectric pickup and the other said plate.

In a piano having a main frame with a string-holding frame supported by and inside said main frame and having strings thereon, a keyboard at the front with keys, and a sounding board,

• an amplifying assembly, comprising
• a support and baffle board secured to said piano and having a support face facing said sounding board and a second face,
• a plurality of pickup means positioned between said sounding board and said support board, in contact with said sounding board, and spaced apart from each other to pick up different frequency ranges of the piano,
• a plurality of amplifier means corresponding in number to said pickup means, supported on the support face of said support board and each connected electrically to a said pickup means, and
• a plurality of enclosed loud speakers corresponding in number to said amplifier means, supported by said support face and each electrically connected to a said amplifier means, said support board having an opening therethrough for an output area of each said loudspeaker, said support board being so positioned relative to said loudspeakers and said sounding board and of such a size as to serve as a baffle preventing feedback from said loudspeaker to said sounding board.

In an upright piano having a main frame with a front and a rear, sides and a top, a string-holding frame supported by and inside said main frame and having strings thereon, a keyboard at the front with keys, and a vertical sounding board to the rear of said string-holding frame, said main frame having a plurality of uprights to the rear of and spaced from said sounding board and having front faces facing said sounding board and rear faces lying on a common plane, the combination therewith of:

• an amplifying assembly, comprising
• a support and baffle board secured to the rear faces of some of said uprights in a vertical position and having a support face facing said sounding board and a rear face,
• a plurality of pickup means positioned between said sounding board and said support board and spaced apart from each other to pick up different frequency ranges of the piano,
• a plurality of amplifier means corresponding in number to said pickup means, supported on the support face of said support board and each connected electrically to a said pickup means,
• a plurality of enclosed loud speakers corresponding in number to said amplifier means, supported by said support face of said support board and each electrically connected to a said amplifier means, said support board having an opening there-through for an output area of each said loudspeaker and being so located and sized as to baffle the feedback of sound from each loudspeaker to the sounding board, and
• a power-supply cord for said amplifier means and loudspeaker means, extending out from said support board.

In an upright piano having a main frame with a front and a rear, sides and a top, a string-holding frame supported by and inside said main frame and having strings thereon, a keyboard at the front with keys, and a vertical sounding board to the rear of said string-holding frame, said main frame having a plurality of uprights to the rear of and spaced from said sounding board and having front faces facing said sounding board and rear faces lying on a common plane, the combination therewith of:

• an amplifying assembly, comprising
• a support and baffle board secured to the rear faces of some of said uprights in a vertical position and having a support face facing said sounding board and a rear face,
• a plurality of pickup means, each comprising
• a ceramic piezoelectric pickup with a metal conductor engaging each side thereof,
• a metal housing having a front plate and a rear plate spaced apart with said ceramic pickup in between them and in electrical contact with said rear plate,
• insulator means between said ceramic pickup and said front plate,
• a backup member of substantial mass secured to said back plate, and
• a coil spring seated on said backup member and engaging the front face of a said upright and urging said front plate against said sounding board, said backup member dampening vibration of said spring,
• a plurality of amplifier means corresponding in number to said pickup means, supported on the support face of said support board and each connected electrically to a said pickup means,
• a plurality of enclosed loudspeakers corresponding in number to said amplifier means, supported by said support face of said support board and each electrically connected to a said amplifier means, said support board having an opening therethrough for an output area of each said loudspeaker and baffling between said loudspeakers and said sounding board to prevent feedback,
• a power-supply cord for said amplifier means and loudspeaker means, extending out from said support board,
• volume control means mounted on the front of said piano and connected electrically to said amplifier means, and
• grille cloth covering the rear face of said support board.

In a piano having a main frame, a string-holding frame supported by and inside said main frame and having strings thereon, a keyboard with keys, and a sounding board, the combination therewith of:

• an amplifying assembly, comprising
• a plurality of pickup means for picking up sound from said sounding board supported on said piano,
• a plurality of amplifier means corresponding in number to said pickup means, supported on said piano and each connected electrically to a said pickup means,
• a plurality of loud speakers corresponding in number to said amplifier means, supported on said piano and each electrically connected to a said amplifier means, and
• baffle means for preventing feedback from said loudspeakers to said sounding board,
• each said pickup means comprising a piezoelectric pickup in a housing that is in direct contact with said sounding board,
• said housing having a front plate and a rear plate spaced apart with said piezoelectric pickup in between them and in electrical contact with one said plate,
• insulator means filling the space between said piezoelectric pickup and the other said plate,
• a backup member of substantial mass secured to said housing, and,
• spring means for urging said front plate against said sounding board,
• the mass of said backup member preventing said piezoelectric pickup from moving with the movement of said sounding board, thereby substantially increasing the electrical output from said piezoelectric pickup.