Not Applicable
The present invention relates generally to stringed musical instruments, and more specifically, to instrument saddles with internally integrated transducers which provide separate electrical outputs for each transducer.
The need for the invention is caused by the struggles of musicians to control and shape the natural acoustic properties of the instrument. Amplification of acoustic instruments often results in the undesirable effect of feedback, where the output of the instrument's amplifier is picked up by the instrument transducer and re-amplified. This results in a high-volume screeching sound. Feedback can be mitigated by filtering the frequency content of the instrument signal to remove frequencies prone to feedback. However, this alters the sound of the instrument making it sound less like it does acoustically. The invention provides the capability to prevent feedback without the need for frequency filtering which alters the amplified sound of the instrument.
Other methods of mitigating feedback sensitivity and reproducing the acoustic sound of the instrument require a plurality of transducers located separately within the structure of the instrument. This complexity has the drawback of being difficult to install and maintain. Additionally, some of these methods negatively affect the acoustic sound of the instrument by limiting the transfer of each string's vibrational energy to the instrument soundboard. The invention solves the problem of complexity by locating the transducers within a single physical structure which comprises the instrument saddle and that contains removable electrical cables for the transducer output signals. This allows for simple installation and maintenance of the pickup. The invention does not have the problem of string energy transfer to the instrument bridge because it is designed to allow energy transfer in the same manner as an instrument with a traditional solid saddle.
Various attempts have been made at solving the problem of natural sound without feedback sensitivity. For example, the U.S. Pat. No. 5,206,449 to McClish discloses dual transducers designed to capture the multidirectional energy of each string which are then separately processed before being summed. While this design may overcome the feedback sensitivity problem and sound natural, it is very complex, requiring multiple transducers and associated processing circuitry, and is therefore expensive.
In another example, U.S. Pat. No. 5,218,159 to McClish discloses a vertical application of pressure to drive a piezoelectric bender. The design uses a suspended string rest having greater central mass to produce a sine wave transmission outward from center. The greater central mass results in a low mass at each end of the string rest where it connects to the base. These connection points are susceptible to failure from lateral forces experienced by the pickup during normal use of the instrument.
The design intends to mechanically isolate the vibrating string from the vibrating instrument soundboard. However, there are two problems with this. First, vibrational energy from the soundboard travels back up the string from its attachment point on the bridge bypassing the mechanical isolation designed into the pickup. Second, because of the mechanical isolation designed into the pickup, the vibrational energy of the string is isolated from the soundboard of the instrument, negatively affecting the acoustic tonality of the instrument.
This design requires an individual saddle with transducer per string or course on the instrument. This requires separate holes in the saddle slot of the bridge for the electrical wires from each pickup to pass into the interior cavity of the instrument to connect to the preamp. This complexity is not widely accepted in the industry because of the work required to install such a pickup system, the perceived harm to the structural integrity of the instrument bridge by the multiple holes through which the cables must pass, and the non-traditional look of individual saddles in the instrument bridge.
U.S. Pat. No. 11,348,563 B2 to Lloyd Baggs Innovations, LLC discloses an improvement on U.S. Pat. No. 5,218,159 to McClish to correct the structural issues of the design. The McClish design features pressed tabs to secure the bender, or string rest, at each end. This weak integration is designed to enhance maximum amplitude of the bender hinged at each end by this pressed fit. However, it is susceptible to mechanical failure as lateral forces experienced in the normal use of the instrument bend the pressed tabs causing the bender, or string rest, to break off from the base. These improvements do solve the structural issues in the McClish design, but at the cost of the motion of the saddle to which the transducer is connected. Like the McClish design, in this design, the transducer only senses string energy in the vertical direction.
This design is designed to be a replacement for the RMC pickup and therefore uses individual saddles for each string or course. It is therefore subject to the same industry acceptance problems as the RMC. The McClish and Baggs designs were and are used by Godin Guitars of Canada. These designs have not been universally accepted aftermarket products for the above-mentioned reasons, irrespective of product capabilities or positive attributes.
An alternative approach is disclosed in the U.S. Pat. No US 2013/0160634 A1 to Taylor Guitars which requires specialized installation of an external transducer contacting the saddle through the side wall of the bridge slot which contains the saddle. In this design the transducer works only in the horizontal direction, picking up the motion of the saddle as it rocks back and forth in the bridge slot.
Because the transducers contact the side of the saddle, significant modifications must be made to the instrument bridge to allow for the location of the transducers. This is not a problem if these modifications are done as part of the instrument manufacturing process, but they are too complicated to be made after the instrument has been built. This limits the implementation of the design to newly manufactured instruments.
Yet another approach is disclosed in the U.S. Pat. No. 7,943,838 B2 to Dunwoodie which features a single piece saddle with an internal cavity open to the bottom of the saddle. A transducer is inserted and secured into this cavity so that the bottom of the transducer is recessed from the open end of the cavity. This mounting method prevents the transducer from being vertically compressed between the top edge of the cavity and the bottom of the bridge slot, which would result in an inferior tonal quality.
The location and mounting of the transducer to the saddle is critical to energy transfer from the saddle to the transducer. If the transducer is not consistently mounted, then each transducer will have a significantly different response characteristic. Consistent mounting is made difficult in this design by the requirement to mount the transducer inside a cavity with adhesive, which is hard to control. Graph Tech's commercial implementation of this design suffers from inconsistent mechanical coupling of the transducer to the saddle. Their commercial implementation also uses individual saddles and transducers for each string or course. Therefore, a time-consuming pickup matching process is required to ensure that each pickup used on an instrument will have sufficiently similar output characteristics. This problem is in addition to the above-described problems with individual saddles and transducers for each string or course.
U.S. Pat. No. 8,507,783 B1 to Barbera discloses the only design reviewed which has been commercially implemented where the transducers for each string or course are contained within a single physical structure. U.S. Pat. No. 7,943,838 B2 to Dunwoodie includes this arrangement, but Graph Tech has not made a commercial product using it. The Barbera design electrically combines all of the transducers into a single output signal rather than leaving each transducer electrically separate as do McClish, Baggs, and Graph Tech.
This design has the benefit of simplicity which the other designs reviewed do not. However, this design has limited mechanical isolation between transducers and only senses vibrations along the vertical axis. The result is that it does not mitigate the risk of feedback as well as the other designs which depend on electrical processing of the individual transducer signals to prevent feedback.
There remains a need for an instrument pickup which combines the simplicity of a single saddle structure as disclosed in the U.S. Pat. No. 8,507,783 B1 to Barbera, but which maintains individual transducer outputs which allows for the best possible feedback mitigation as seen in the U.S. Pat. No. 5,218,159 to McClish, U.S. Pat. No. 11,348,563 B2 to Lloyd Baggs Innovations, LLC. Additionally, the pickup design should not mechanically isolate the string from the bridge as seen in U.S. Pat. No. 5,206,449 to McClish, U.S. Pat. No. 5,218,159 to McClish, U.S. Pat. No. 11,348,563 B2 to Lloyd Baggs Innovations, LLC, and U.S. Pat. No. 8,507,783 B1 to Barbera because this isolation is detrimental to the acoustic sound of the instrument.
The present invention comprises a novel stringed instrument pickup generally consisting of a plurality of piezoelectric transducers mounted in the cavities created by a laminate structure of two or more layers of solid material such as fiberglass or aluminum. The laminate structure will be capped with a string rest so that the entire device comprises an instrument saddle. One or more layers of the laminate may contain one or more layers of copper etched to comprise a single or greater layer circuit board. The individual transducer signals will be conveyed through the laminate structure on one or more layers of one or more laminate pieces to reach a connector. The invention will contain one or more connectors for removable cables which will convey the transducer signals to the preamp. The string rest as well as the bottom of the saddle will have the ability to be shaped by an instrument technician such that the instrument will maintain optimum playability.
The transducers are rigidly mounted to the inside of each cavity on 2 faces, the sidewall of the cavity and the bottom of the string rest such that string vibrational energy is then received in two perpendicular directions, lateral and vertical. Because the transducer senses string vibrational energy in these two directions, it is less sensitive to the distance between the top of the transducer and the top of the string rest. In designs which pickup string vibrational energy in only the downward direction from the string, the transducer output level will be inversely proportional to the distance from the string. Two directional sensitivity reduces the output variation caused by string height over the bridge, radius required to match fretboard radius, and staggering of string length over the width of the string rest to provide proper string intonation. Consequently, the invention acts as a traditional instrument saddle while maintaining sufficiently similar output characteristics between all transducers within it.
Like reference symbols in the various drawings indicate like elements.
Referring to
Referring now to
Each laminate layer 12, 13, and 14 is adhered to any abutting laminate layer 12, 13, and 14 by an adhesive layer 35 such as glue, epoxy, adhesive film, or solder. This adhesive layer 35 may be more easily seen in
Internal to this saddle 110 are a plurality of piezoelectric transducers 21 (shown in
The string rest 11 is able to be shaped by a technician. This shaping may be required to set the total height of the saddle 110, to create a radius which matches the radius of the neck 103, or to properly intonate the strings 108. The bottom of the saddle 110 may also be sanded in order to reduce the total height of the saddle 110.
Referring now to
In some embodiments of the invention, electrical components such as a resistor 99 which constitute a part of the remote preamp 90 (see
While specific embodiments of the invention have been illustrated and described, such embodiments should be considered illustrative and not as limiting the invention as construed in accordance with the accompanying claims.
This application claims the benefit of U.S. Provisional Application Ser. No. 63/220,185 titled “Novel Acoustic Instrument Pickup Contained Within the Instrument Saddle and Accompanying Electronic Preamp,” filed by Benjamin Shaw and Paul McGill on Jul. 9, 2021.
Number | Date | Country | |
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63220185 | Jul 2021 | US |