Techniques are described that relate to various aspects of converting the mechanical energy of instrument strings to digital representations for use in a variety of applications.

A single axis position transducer uses an elongate permanent three pole magnet having a radial magnetic field at a spot along the magnet in which the magnetic field has radial field lines that decay as 1/R. R is the distance from the center of the magnet along a radial field line perpendicular to the axis of the magnet. The spot has a first pole of one polarity, and the magnet has poles of the opposite polarity spaced along the magnet on opposite sides of the first pole of the radial magnetic field located at the spot. At least one magnetic field sensor is positioned proximal to the spot along the elongate member that detects the motion of the spot and electrically amplifies the sensor output.

Apparatus and associated methods relate to acoustic-electric sensor system including a main acoustic sensor operably coupled to detect string vibrations of an acoustic-electric instrument and a feedback suppression acoustic sensor configured to primarily detect sound board vibrations of the acoustic-electric stringed instrument at a location with a substantially attenuated string vibration signal relative to its sound board vibration signal. In an illustrative example, a mixing circuit may at least partially cancel out sound board vibration signatures output by the main and feedback suppression acoustic sensors with one another to produce a mixed output signal. The feedback suppression acoustic sensor may be spaced outside of an ellipse substantially centered around a sound board string coupling point. The main acoustic sensor may be arranged in close proximity to receive the string vibration signal. The mixed output signal may substantially reject audio feedback disturbances while retaining the unique characteristic sound of the instrument.

A switching device receives an output cable from a guitar. The output cable has a plurality of conductors corresponding to each of the pickups on the guitar, typically 2 or 3. A passthrough signal based on manually switched pickup selection corresponds to a main guitar output. A pickup buffer circuit on the guitar isolates the signal conductors from the selected passthrough signal, and also switches the pickup buffer circuit on and off to allow for backwards compatibility. A multi-conductor cable and jack simultaneously transmits the plurality of signals to the switching device. The switching device receives the multi-conductor cable. A combination circuit in the switching device combines the signals from the pickups and also delivers the individual pickup signals to a respective output jack. Each output jack simultaneously delivers the respective pickup or combined signal to a mixer, amplifier or other signal processing device for recording and/or further processing.

This invention discloses a switching system for any odd or even number of two or more matched vibrations sensors, such that all possible circuits of such sensors that can be produced by the system are humbucking, rejecting external interferences signals. The sensors must be matched, especially with respect to response to external hum and internal impedance, and be capable of being made or arranged so that the responses of individual sensors to vibration can be inverted, compared to another matched sensor, placed in the same physical position, while the interference signal is not. Such that for 2, 3, 4, 5, 6, 7 and 8 sensors, there exist 1, 6, 25, 90, 301, 966 and 3025 unique humbucking circuits, respectively, with signal outputs that can be either single-ended or differential. Embodiments of switching systems include electro-mechanical switches, programmable switches, solid-state digital-analog switches, and micro-controller driven solid state switches using time-series to spectral-series transforms to pick the order of tones from bright to warm and back.

This invention discloses and claims means and methods for producing a continuous range of humbucking vibration signals from matched sensors, from bright to warm tones, using variable gains, with either manual control or automatic control by a digital micro-computing device and system. It shows how electronic circuits can control the linear combination of tones from humbucking pairs of sensors, based upon simulating humbucking basis vectors.

A saddle assembly for a stringed musical instrument comprising a saddle footing having a body of any desired geometry and a surface curvature compatible with and conforming to the surface curvature of the soundboard of the stringed musical instrument upon which the body of the saddle footing is mounted with or without the use of a bridge plate, with the saddle footing adapted to accommodate either a conventional bridge or conventional saddle for elevating the strings in the stringed musical instrument relative to the soundboard or upon which a modified bridge or modified saddle is mounted having a geometry which conforms in geometry and curvature to the geometry and curvature of the elongated slot in the saddle footing.

Electronic musical instruments as disclosed, include sensors to digitize and alter the sound using FSR sensors in the mouthpieces and other elements of the instrument to mimic the variations available in analog instruments.

A sound detection system of a musical instrument with vibrating parts includes at least a pair of sensors and a preamplification unit for processing the signal output from the two sensors along respective channels. At least one of the pair of sensors is a piezoelectric transducer and the other one of the pair of sensors is a different-type transducer. The preamplification unit includes, for each channel, an input stage, including an amplifier circuit and an equalization circuit, and an output stage including at least a weighted adder circuit and at least two volume controls with arbitrary logarithmic response curve. At least the input stage for the channel of the piezoelectric transducer is a charge amplifier circuit and at least one of the other input stages can be configured both as a charge amplifier and as non-inverting amplifier with high input impedance. The equalization circuit includes an RC circuit.

A musical instrument having a hollow or semi-hollow body and a sound board, representing either the anatomical front surface or the anatomical rear surface of the hollow body, or with the front surface and the rear surface both functioning as a sound board for the musical instrument and having at least one tuned sound port located in either the front and/or rear sound board of the musical instrument through which sound can exist with the tuned sound port comprising a hollow member adapted to be inserted through a hole formed in one or both of the sound boards and having a central opening of predetermined geometry and a length extending a fixed distance from the sound board into the interior of the musical instrument of between 5% and 95% of the distance between the front rear sound surfaces of the musical instrument. The musical instrument is preferably a stringed musical instrument which may include a plurality of panels extending between the front and rear sound boards for enhancing the structural support of the musical instrument and for funneling sound through the tuned sound ports or alternatively the musical instrument may include a plurality of panels extending between the front and rear surfaces without a tuned sound port.