String instrument pickup system

Claim 2

In a string instrument having a body with a generally flat upper portion and a plurality of strings spaced above and arranged generally parallel to said upper portion of the body of the instrument, a pickup which comprises: a plurality of piezoelectric transducers spaced apart from each other and located generally between said plurality of strings and said upper portion of the body of the instrument and being responsive to compressional variations directed generally normal to said upper portion of the body of the instrument, each of said piezoelectric transducers having upper and lower parallel faces, the sum of the areas of all of said upper faces comprising an area of sensitivity substantially parallel to said upper portion of the body of the instrument, and string support means compressionally engaged between said plurality of strings and said plurality of piezoelectric transducers so as to apply compressional variations to said piezoelectric transducers in response to movements of said strings in said generally normal direction, whereby said piezoelectric transducers are sensitive to such generally normal string movements, substantially half of the total area of said area of sensitivity being electrically polarized in one direction, and substantially the other half of such total area being polarized in the opposite direction for cancellation of microphonics.

Claim 3

A pickup as defined in claim 1, which comprises six piezoelectric transducers located generally between six of said strings and the body of the instrument.

Claim 4

In a string instrument having a body with a generally flat upper portion and a plurality of strings spaced above and arranged generally parallel to each other and to said upper portion of the body of the instrument, a pickup which comprises: a plurality of piezoelectric transducers arranged in an elongated array having a longitudinal axis generally parallel to said upper portion of the body of the instrument and generally transverse to said strings; upwardly facing surface means on said upper portion of the body of the instrument upon which said transducers rest; string support means compressionally engaged between said strings and said transducers so as to apply compressional variations to said transducers in response to movement of said strings; and transducer support means supporting said array of transducers in elongated, modular form, said transducer support means generally enclosing the tops, sides and bottoms of said transducers, and at least the upper portion of said support means above said transducers being pliable and thereby conformable to deformations in said string support means so as to provide substantially uniform responses of said transducers to said strings; said transducer support means comprising an outer wrapping comprising electrically conductive metal foil; said transducer support means comprising a body of flexible, electrically insulative material within which said piezoelectric transducers are located, said body having a plurality of cutout windows extending therethrough in the upward-downward direction and corresponding in number to the number of said transducers, each of said transducers being located in a respective said window; said transducers each being generally flat, with upper and lower electrodes on opposite flat surfaces thereof which are generally parallel to said upper portion of the instrument body, said electrodes of each transducer being exposed on opposite sides of said pickup body, and elongated upper and lower electrical contacts of generally flat, electrically conductive sheet material engaged generally flat against the respective said upper and lower electrodes of said transducers, at least one of said contacts being electrically insulated from said outer wrapping.

Claim 5

In a string instrument having a body with a generally flat upper portion and a plurality of strings spaced above and arranged generally parallel to each other and to said upper portion of the body of the instrument, a pickup which comprises: a plurality of piezoelectric transducers arranged in an elongated array having a longitudinal axis generally parallel to said upper portion of the body of the instrument and generally transverse to said strings; upwardly facing surface means on said upper portion of the body of the instrument upon which said transducers rest; string support means compressionally engaged between said strings and said transducers so as to apply compressional variations to said transducers in response to movement of said strings; and transducer support means supporting said array of transducers in elongated, modular form, said transducer support means generally enclosing the tops, sides and bottoms of said transducers, and at least the upper portion of said support means above said transducers being pliable and thereby conformable to deformations in said string support means so as to provide substantially uniform responses of said transducers to said strings; said transducer support means comprising an outer wrapping comprising electrically conductive metal foil; said transducer support means comprising a body of flexible, electrically insulative material within which said piezoelectric transducers are located, said body having a plurality of cutout windows extending therethrough in the upward-downward direction and corresponding in number to the number of said transducers, each of said transducers being located in a respective said window; said transducers each being generally flat, with upper and lower electrodes on opposite flat surfaces thereof which are generally parallel to said upper portion of the instrument body, said electrodes of each transducer being exposed on opposite sides of said pickup body, and elongated upper and lower electrical contacts of generally flat, electrically conductive sheet material engaged generally flat against the respective said upper and lower electrodes of said transducers, at least one of said contacts being electrically insulated from said outer wrapping.

Claim 6

A pickup as defined in claim 3, wherein said upper contact comprises metal foil.

Claim 7

A pickup as defined in claim 4, wherein said upper contact is a hot electrical contact and said lower contact is a ground electrical contact; and a coaxial cable leading from said pickup, said cable having an outer shield mechanically and electrically connected to said lower contact and inner conductor means extending upwardly through an aperture in said body and electrically connected to said upper contact.

Claim 8

A pickup as defined in claim 5, wherein said inner conductor means of said cable comprises a plurality of wire strands, said strands being compressed between said upper contact and said body.

Claim 9

In a string instrument having a body with a generally flat upper portion and at least four strings spaced above and arranged generally parallel to each other and to said upper portion of the body of the instrument, a pickup system which comprises: a plurality of piezoelectric transducers corresponding in number to said number of strings arranged in an elongated array having a longitudinal axis generally parallel to said upper portion of the body of the instrument and generally transverse to said strings; upwardly facing surface means on said upper portion of the body of the instrument upon which said transducers rest with each of said transducers lying generally under a respective one of said strings; and elongated saddle means arranged generally parallel to said elongated array of transducers and engaged between said strings and said transducers so as to mechanically compressionally couple each of said transducers to its respective said string whereby compressional variations are applied to each of said transducers in response to movement of its respective said string; said saddle means being transversely split into two elongated sections to increase the uniformity of response of said crystals to their respective said strings, one of said saddle sections being engaged between one plural sequence of said strings and their respective said transducers, and the other of said saddle sections being engaged between another plural sequence of said strings and their respective said transducers.

Claim 10

In a string instrument having a body with a generally flat upper portion and at least four strings spaced above and arranged generally parallel to each other and to said upper portion of the body of the instrument, a pickup system which comprises: a plurality of piezoelectric transducers corresponding in number to said number of strings arranged in an elongated array having a longitudinal axis generally parallel to said upper portion of the body of the instrument and generally transverse to said strings; upwardly facing surface means on said upper portion of the body of the instrument upon which said transducers rest with each of said transducers lying generally under a respective one of said strings; and elongated saddle means arranged generally parallel to said elongated array of transducers and engaged between said strings and said transducers so as to mechanically compressionally couple each of said transducers to its respective said string whereby compressional variations are applied to each of said transducers in response to movement of its respective said string; said saddle means being transversely split into two elongated sections to increase the uniformity of response of said crystals to their respective said strings, one of said saddle sections being engaged between one plural sequence of said strings and their respective said transducers, and the other of said saddle sections being engaged between another plural sequence of said strings and their respective said transducers.

Claim 11

A pickup system as defined in claim 7, wherein said strings are six in number, and each of said plural sequences comprises three strings.

Claim 12

A pickup system as defined in claim 8, wherein each of said plural sequences comprises an outer string, an inner string, and a center string between said outer and inner strings; said center string in each of said plural sequences being more directly located over its respective said transducer than said outer and inner strings are over their respective said transducers to increase the uniformity of response of said crystals to their respective said strings in each of said plural sequences.

Claim 13

A pickup system as defined in claim 9, wherein each of said outer strings is located approximately over the outer edge of its respective said transducer, each of said inner strings is located approximately over the inner edge of its respective said transducer, and each of said center strings is approximately centrally located over its respective transducer.

Claim 14

A pickup system as defined in claim 7, wherein each of said transducers is not more than approximately 5/32 inch long in the longitudinal direction of said array.

Claim 15

A pickup system as defined in claim 11, wherein each of said transducers is not less than approximately 0.025 inch thick in the direction generally normal to said upper portion of the body of the instrument.

Claim 16

A pickup system as defined in claim 7, wherein each of said transducers is not more than approximately 1/8 inch long in the longitudinal direction of said array.

Claim 17

A pickup system as defined in claim 13, wherein each of said transducers is not less than approximately 0.030 inch thick in the direction generally normal to said upper portion of the body of the instrument.