Abstract: A drum head for a drum made of a natural and/or synthetic material or composite material which is designed to be attached to a drum head rim. The drum head includes a one or more sound producing devices that produces one or more distinct sounds. The sound producing device can be a mechanical device and/or electrical devices. The sound producing device can be connected to the top, bottom and/or side of the drum head.

Abstract: A protective cover for use with a stringed musical instrument comprises a roof-like shaped shield body attachable to the stringed instrument to protect the most sensitive parts and areas at and around the vertically mounted bridge, the string combination and other parts attached to the body of the instrument. The shield body has a concave bottom side and an inner string channel open to the bottom side and designed to accomodate the bridge and the strings. The shield body is made of elastically deformable material and has on its sligtly arched bottom side within an intermediate zone thereof locking projections designed to engage instrument recesses and projections, the latter being formed e.g. by a fingerboard end portion an the space therebelow.

Abstract: Disclosed is a guitar string tuning device.

Abstract: A transmission structure for simulating actions of a cradle is disclosed. The transmission structure comprises a frame, gears, a slidable seat, and other components. The frame is fixed above a music bell. A driving gear is installed at the groove of the frame; and a transmission gear is installed between the lower portion of the frame and the teeth of the roller. The driving gear is engaged with the transmission gear. A slidable seat is installed at the upper surface of the frame. The notch of the slidable seat is at the pin position of the driving gear. By the aforesaid structure, as the transmission gear is driven by a music bell, the slidable seat is pushed by the pin of the driving gear so as to move straightly and repeatedly.

Abstract: The improvement in an acoustical musical stringed instrument having a flat soundboard with opposite top and bottom surfaces employing a plurality of elongated struts secured to the bottom surface of the soundboard in spaced apart positions. The struts cause the first side of the top surface of the soundboard to function as if it were stiffer and relatively short and wide and cause the second side of the top surface to function as if it were more compliant and relatively longer and narrower. The struts are progressively graduated in width and length from shorter and wider struts secured to the first side of the bottom surface to longer and narrower struts secured to the second side of the bottom surface whereby when the strings of the instrument are plucked to produce sound, the resonant frequency is enhanced by increasing the number of harmonics of higher frequency of the resonant frequency and the richness of sound is substantially enhanced.

Abstract: An exhaust gas muffler for an internal combustion engine, especially in a manually guided implement such as a power chain saw and the like, is provided. The muffler has a housing having an inlet opening and an outlet for engine exhaust gas. An essentially cylindrical spark killer screen is fixed in position at a wall opening of the muffler housing that forms the outlet. The spark killer screen projects into the interior of the muffler housing. Adjoining the spark killer screen on the outer side of the muffler housing as an extension of the cylindrical spark killer screen is an exhaust gas pipe. This pipe is provided with threads and serves as a fastening device with which the spark killer screen and the exhaust gas pipe, as a fire protector, are fixed in position in the wall opening of the muffler housing.

Abstract: A guitar soundboard assembly is comprised a plurality of internal braces attached to an inner side of a soundboard for resisting warping. The soundboard is relatively thick for a longer useful life. The braces include two cantilever braces extending between opposite sides of the soundboard. Each cantilever brace is comprised of an elongated bar supported in a spaced position behind the soundboard by a pair of mounting blocks at its ends. Although the soundboard is relatively thick, the portions between the mounting blocks of the cantilever braces are free to vibrate, so that it can vibrate as much as a thinner conventional soundboard. The bases of the mounting blocks of the cantilever braces are slightly angled relative to each other to arch the soundboard forwardly for further increasing stiffness and resisting cave in.

Abstract: An apparatus for marking slide positions on a conventional trombone having an inner hollow slide slidingly journalled in an outer hollow slide includes a magnet sensor mountable on the outer hollow slide for sensing proximity of a magnet mounted within the inner hollow slide. The magnet sensor may be first magnets mountable in longitudinally spaced apart slide positions on the outer hollow slide. A second magnet is mountable within the inner hollow slide. The magnet sensor indicates the proximity of the second magnet by feedback to a user sliding the outer hollow slide over the inner hollow slide.

Abstract: A guitar slide 10 includes a cylindrical body 20 defining an internal cavity 21. The cavity is defined by a very gradually tapered inner surface 25 which tends to result in a frictional connection with the musician's finger. A forward opening 30 is reduced in diameter by a neck 40 having an annular inner surface 41 with a diameter smaller than the tapered inner surface 25 of the cylindrical body. A curved transition surface 42, between the annular inner surface of the neck and the tapered inner surface 25 of the cylindrical body, tends to grip the tip of the musician's finger when the finger is gently forced toward the forward opening. A rear opening 50 is defined between a semi-circular rim 51 and a crescent-shaped rim 52, resulting in an opening which provides access to the internal cavity 21 from the direction perpendicular to the length of the cylindrical body 20. A finger rest 60 includes a flat surface 61 which is bordered by the outer surface of the cylindrical body.

Abstract: A stringed instrument having a body and a neck with a fingerboard extending from the body. The body has a bridge for supporting first end portions of a plurality of strings arranged in a series of decreasing thickness, and a nut at an end of the fingerboard is placed so as to provide support for a second end portion of the plurality of strings. The fingerboard has a pluarlity of frets located between the bridge and the nut, where the first fret is defined as the fret closest to the nut. The distance between the nut and the first fret for each of the plurality of strings is inversely proportional to the thickness of the corresponding string so that a thin, high pitched string has a greater distance between the nut and the first fret than does a thicker, lower pitched string.

Abstract: A keyboard assembly is constructed by assembling keyboard units. Herein, a hook is formed at one end of the keyboard unit, while an engaging portion (e.g., recess) is formed at another end of the keyboard unit. So, the keyboard units are assembled together in such a way that a hook of a keyboard unit engages with a recess of an adjacent keyboard unit. The keyboard unit is constructed by piling up at least a white key unit having white keys and a black key unit having black keys. Each key unit is formed by the resin to integrally contain keys, connections and a key support. The keys are connected to the key support by the connections such that each of the keys is supported to have a capability of swinging up and down in key-depression-release directions. The connection is constructed by a thick-wall portion whose width is greater than a width of a back end of the key and a thin-wall portion which works as a hinge.

Abstract: A guitar construction having a complete body, neck, and head, formed as a single, integral wooden carving with tuning pegs, fingerboard, bridge, nut, and strings mounted thereon. The body portion is in the usual bell-shaped outline. Conventional pick-up means for an electronic amplification system may be mounted to the body.

Abstract: A self-contained tremolo for a guitar or other stringed instrument provides exceptional ease of setup and operation. The tremolo has a base plate fastened to the guitar over a small cavity. A bridge is pivotally connected to the base plate by means of bridge pins that enter blind slots in the base plate. String tension is counteracted by a spring mechanism that includes studs received in the bridge and passing through holes in the base plate and entering the guitar cavity. Compression springs act between the studs and the base plate. Identical intonation blocks are held on steps in the bridge such that the contact points between the intonation blocks and the strings lie along a curved line that matches the curve of the guitar frets. Fine tuners have plugs with V-grooves that contact the strings. The plugs are held in threaded shanks, but they do not rotate with the shanks during fine tuner adjustment, thereby eliminating the tendency of the strings to twist or slip off the ends of the fine tuners.

Abstract: A stringed musical instrument including a bowl portion having an open upper end and a closed lower end. The bowl portion has a pair of diametrically opposed openings therein downwardly of the open upper end. The open upper end has a cover secured thereto. An elongated rod extends through the pair of diametrically opposed openings of the bowl portion. The elongated rod has opposed ends disposed outwardly with respect to the bowl portion. A first opposed end is disposed in proximity to the bowl portion. A second opposed end is disposed remotely with respect to the bowl portion. A bridge is secured to the cover of the bowl portion. A length of steel wire is provided having a first end secured to the first opposed end of the elongated rod. The length of wire has a second end extending over the bridge for coupling with respect to the second opposed end of the elongated rod.

Abstract: A visual display is provide for music associated with a theremin or, in general, any space-controlled electric instrument. The theremin is a space-controlled electric instrument that produces an output of sound corresponding to the motion of the user, without being touched by the user. The device establishes a correspondence between motion and electric signals, then between such signals and either light and sound, or just light.

Abstract: A spring and support structure connected through a cam with a rotary shaft for urging the rotary shaft toward a first rotation orientation. The spring urging the shaft to return toward the first rotation orientation when the shaft is rotated off that first orientation. A cam is affixed to and rotates with the shaft. A spring support is pivotally connected to the cam at a bearing between them. A spring extends between the spring support and a support base for urging the shaft and the cam toward the first orientation. The spring support includes a window larger in size than the bearing. The window periphery having an insertion groove in which the bearing sits. The bearing is easily insertable into the window and removable therefrom due to the window size. The spring support is comprised of an inside and outside member which have openings facing in opposite circumferential directions.

Abstract: A system for operating a plurality of motors with a single controller is disclosed. This system includes a first motor, a second motor that is matched to the first motor but has a lower power rating than the first motor and a controller electrically driving the first and second motors with a modulated voltage at one frequency selected from one or more frequencies over a complete range of frequencies. The controller generates a frequency of the modulated voltage from the range of frequencies which is proportional to the desired speed for the first and second motors. A method for building such a system is also disclosed. This system and method have particular application to HVAC systems.

Abstract: A keyboard musical instrument has an instrument housing and a keyboard chassis integrally formed as a single piece. The keyboard musical instrument has at least one key movably supported on the keyboard chassis, a lower limit stopper for limiting the lowest descending position of the at least one key, a key switch including a movable contact and a fixed contact provided between the at least one key and the keyboard chassis, and an upper limit stopper disposed between the at least one key and the keyboard chassis for limiting an upper-most ascending position of the at least one key. The upper limit stopper is provided on a member that is independent of the keyboard chassis.

Abstract: A striking mechanism for a string instrument, such as a piano or a grand piano, which has, for each string, a hammer, which, via a power transmission, is brought to strike the string when the associated key in the keyboard of the instrument is depressed. The mechanism includes first and second checks having, respectively, first and second check zones for, in mutual engagement, stopping and temporarily retaining the hammer during rebound. A magnetic or magnetizable material is placed in each check zone to generate a magnetic field which causes the hammer during rebound to obtain a much safer and softer braking than is the case in conventional striking mechanism. Thus, the risk of the hammer rebounding and striking the string in an unintended repetition strike is eliminated.

Abstract: A universal split ring ligature that is versatile enough to fit differing sized mouthpieces. The ligature of the invention accomplishes this by comprising two elongated inverted U-shaped ring retaining bars that have at least one but preferably two or more apertures disposed therein through the vertical side faces of the U-shape ring retaining bars. Multiple sized metallic (or non-metallic equivalent such as plastic, nylon, etc.) rings or bands having concentric apertures disposed in their opposite ends may be inserted within the U-shaped retaining bars and whereby these opposite ends of the multiple sized rings or bands are drawn together by use of suitable thumbscrews penetrating through said cooperating band and U-shaped ring retaining bars' apertures, so as to unyieldingly embrace and clamp a reed that may be disposed between the ring or band and the mouth piece of the wind instrument.