Abstract: An input signal is applied to a notch filter having a transfer function that is the inverse of the expected noise signal. The filtered signal is coupled to a first amplifier and the input signal is coupled to a second amplifier. The outputs of the amplifiers are summed. The gains of the amplifiers are oppositely adjusted in response to the magnitude of the input signal. At low amplitude, the filtered signal is amplified more than the unfiltered signal. At high amplitude, the unfiltered signal is amplified more than the filtered signal.

Abstract: A packaging device for musical instrument strings provides for easy identification and dispensing of individual strings without bending, curling or tangling the strings. Each string is individually wound on its own string carrier such that the string can be individually removed without disturbing the remaining strings. In one embodiment, a base and cover enclose a series of string carriers with each string carrier having a channel holding a coiled string. The various string carriers may be stacked together and enclosed by an external housing such that the string carriers are allowed to individually rotate, or the carriers may remain fixed with respect to each other and to the package housing. The package may be formed of thermoformed plastic, injection molded plastic, cardboard, or any other material. The dispenser may be used to package strings for guitars, pianos, harps or any other stringed instrument.

Abstract: Guitar pickups are provided herein comprising an upper bobbin, a ferromagnetic steel plate and a lower bobbin, stacked on top of each other, oriented longitudinally and laterally substantially the same, and held together by ferromagnetic screws. An upper coil is wounded around a middle section of the upper bobbin, and a lower coil is wounded in an opposite manner around a middle section of the lower bobbin, whereby the upper and lower coils are connected in series. The upper and lower bobbins, and steel plate each include a plurality of coaxial apertures to receive corresponding permanent magnetic pole pieces that extend from the upper bobbin to the lower bobbin. The upper and lower bobbins include additional apertures to receive ferromagnetic cylinders to selectively change the tonal characteristics of the guitar. The pickups may include a pair of ferromagnetic plates attached to the longitudinal sides of the lower bobbin that extend upwards to about the middle of the upper coil.

Abstract: Guitar pickups are provided herein comprising an upper bobbin, a ferromagnetic steel plate and a lower bobbin, stacked on top of each other, oriented longitudinally and laterally substantially the same, and held together by ferromagnetic screws. An upper coil is wounded around a middle section of the upper bobbin, and a lower coil is wounded in an opposite manner around a middle section of the lower bobbin, whereby the upper and lower coils are connected in series. The upper and lower bobbins, and steel plate each include a plurality of coaxial apertures to receive corresponding permanent magnetic pole pieces that extend from the upper bobbin to the lower bobbin. The upper and lower bobbins include additional apertures to receive ferromagnetic cylinders to selectively change the tonal characteristics of the guitar. The pickups may include a pair of ferromagnetic plates attached to the longitudinal sides of the lower bobbin that extend upwards to about the middle of the upper coil.

Abstract: A pickup has an upper bobbin which is elongated along a longitudinal plane, a lower bobbin which is elongated along the longitudinal plane, permanent magnetic pole pieces situated within holes in the upper and lower bobbins, screws holding said bobbins together, a lower winding wound longitudinally around the lower bobbin, and a single, uniformally flat non-magnetized ferromagnetic plate having opposing ends. The ends are parallel to the longitudinal plane and terminate in a plane approximately below the upper winding. The plate is completely dispose beneath the bobbins and parallel thereto.

Abstract: A guitar neck incorporating a mechanism for adjusting the degree of straightness of the neck's elongated body is provided herein. The mechanism incorporates a lever and tension-compression system to perform the neck adjustment. The lever and tension-compression system includes a platform and a driver connected pivotally to each other in end-to-end relationship. The platform acts as a lever, and the driver creates tension and actuates the lever. The platform and driver are mounted longitudinally of the neck in a groove (slot or passage), the upper and lower wall of which are adjacent to the platform. Pivot points are provided, preferably on the upper and lower walls of the groove, and cooperate with the platform in achieving the proper lever action.

Abstract: A highly portable stereo sound system comprising mixing console-amplifier and speakers. The mixing console-amplifier has spaced-apart front and back sides which have spaced apart upper and lower regions. The first and second speakers are removably mounted respectively on the front and back sides of the console-amplifier, by mating inserts, sockets and latches on the upper and lower regions. The console-amplifier may be a hollow body molded of synthetic resin for containing electronic sound-system elements, and may have control elements for controlling the electronic sound-system elements mounted on the front side. The speakers may also have a hollow body molded of synthetic resin, and may have a side adapted to project sound. The sound-projecting side of the speaker may be shaped and sized to mate with the front or back sides of the console-amplifier.

Abstract: The signal from a piezo-electric transducer in an electro-acoustic guitar is modified by a variable depth notch filter. The notch filter includes two paths between an input and a summation circuit. The signals in the two paths are 180.degree. out of phase and one of the paths includes a bandpass filter. The notch is located at approximately 5 khz. The depth of the notch depends upon either the broadband amplitude or the narrowband amplitude of the signal from the transducer and the depth of the notch is controlled using either feedback or feedforward control.

Abstract: A musical instrument amplifier has all solid state amplification stages but incorporates a pair of vacuum tube signal magnitude limiters to provide vacuum tube type sound when the amplifier is operating in a nonlinear condition. The vacuum tubes are connected to have no supply potential so as to minimize microphonics and are each provided with a small amount of reverse bias to provide a desirable shape of the tube conduction curve and space charge suppression.

Abstract: An apparatus by which both tremolo action and string clamping and string intonation adjustment are achieved effectively and in a very small space. Adjustment screw shanks are threaded into bores in the inertia bar or block of the tremolo, and bear against the heads of pull screws that are connected to string-clamping saddles. The heads of the pull screws are received in recesses in the inertia bar; the inertia bar is connected to the bridge plate by several screws that do not interfere with the screw shanks. To adjust intonation, the bridge plate is pivoted upwardly and a wrench is employed to rotate the screw shanks, which in turn bear against the heads of the pull screws. Furthermore, the pull screws are rotated to release positions while the bridge plate is in its upwardly-pivoted position. After intonation is adjusted, the pull screws are rotated to lock the saddles in their desired positions.

Abstract: An audio mixer console and a power amplifier are mounted in a self contained carrying case that provides both protection for the console and amplifier during transportation and storage and a support during use. A power amplifier is fixedly connected between lower portions of first and second spaced sides at the upper end of which is pivoted a front section of the mixer console. In stored position the mixer console extends downwardly between the sides to a position adjacent the amplifier, and a detachable cover is secured to the sides to extend over both the mixer console and amplifier. Parts of the mixer console and amplifier form at least portions of a forward cover of the completed carrying case.

Abstract: A set-neck guitar in which the inner neck end has a tongue that seats in and is glued in a pocket in the body and in a protuberance on the body. Corresponding sidewalls of the tongue and pocket are parallel to the center line of the body, while other sidewalls are at an angle thereto so as to create a wedge relationship. A cam and bearing element is provided to force the wedge surfaces together and improve the connection. The underside of the protuberance on the body is carved back, as is part of the neck, to create a generally integral-seeming joint. Crush points are provided to facilitate the operation and enhance esthetics.