Abstract: Methods and apparatus provide for: a rectification circuit operating to convert a source of AC power into a final DC power source; a rectification filtering capacitance operating to at least partially smooth a voltage of the final DC power source, which exhibits a voltage sag and recovery characteristic in response to time-variant current drawn therefrom; a power amplification circuit drawing power from the final DC power source and producing an output signal, for driving a speaker, having audible characteristics influenced by the voltage sag and recovery characteristic of the final DC power source; and a control circuit operating to continuously vary, in response to user input, one or more parameters of the voltage sag and/or recovery characteristic of the final DC power source.

Abstract: A drum includes a shell having first and second, spaced apart ends defining an interior volume; first and second drumheads, each stretched over a respective one of the first and second ends of the shell; and an electromechanical driver having a moving coil element operable to move the first drumhead in response to an electrical drive signal.

Abstract: Methods and apparatus provide for: a rectification circuit operating to convert a source of AC power into a final DC power source; a rectification filtering capacitance operating to at least partially smooth a voltage of the final DC power source, which exhibits a voltage sag and recovery characteristic in response to time-variant current drawn therefrom; a power amplification circuit drawing power from the final DC power source and producing an output signal, for driving a speaker, having audible characteristics influenced by the voltage sag and recovery characteristic of the final DC power source; and a control circuit operating to continuously vary, in response to user input, one or more parameters of the voltage sag and/or recovery characteristic of the final DC power source.

Abstract: A drum includes a shell having first and second, spaced apart ends defining an interior volume; first and second drumheads, each stretched over a respective one of the first and second ends of the shell; and an electromechanical driver having a moving coil element operable to move the first drumhead in response to an electrical drive signal.

Abstract: An acoustic guitar includes: a body having a soundboard, a back, and sides defining an interior volume thereof; a neck extending away from the body; a plurality of strings, each stretched from a first end at the body to a second end at a terminal end of the neck; and a plurality of resonant augmenters disposed within the interior volume of the body, each resonant augmenter being coupled at one edge in lever fashion to a mounting plate, the mounting plate being coupled to the soundboard, wherein one or more of the resonant augmenters are sized and shaped to resonate at one or more respective fundamental frequencies.

Abstract: An acoustic drum includes: a shell having first and second, spaced apart ends, and an interior surface defining an interior volume; a drumhead stretched over the first end of the shell; and at least one resonator coupled at one edge in lever fashion to the interior surface of the shell, the at least one resonator being sized and shaped to resonate at a frequency proximate to a peak resonant frequency of the drum.

Abstract: A guitar and strap address the shortcomings of convention guitar design and strap design such that the guitar may be suspended from the strap with a front plane of the guitar oriented generally horizontally, and with the higher frets of the guitar easily accessed by the player's fret-hand.

Abstract: A guitar and strap address the shortcomings of convention guitar design and strap design such that the guitar may be suspended from the strap with a front plane of the guitar oriented generally horizontally, and with the higher frets of the guitar easily accessed by the player's fret-hand.

Abstract: A portable sound unit is shown having a central case and one or more speakers. Each speaker has tongue rails around a portion of its circumference. The central case includes an openable lid permitting access to sound equipment contained within the central case. The central case has openings at either end when the lid is closed and grooves inside a portion of the central case near each opening. The grooves receive the tongue rails on the speaker when the lid is open. Upon positioning a speaker in the grooves in the central body, the lid may be closed, thereby securing the speakers to the central case. When the speakers are separated from the central case and electronically coupled to the sound equipment, the opened lid may serve as a lectern.

Abstract: The present invention is directed to methods and apparatus for dissipating heat in a voice coil of a loudspeaker, where at least one of: a bobbin having a substantially cylindrical shaped wall member is operable to support the voice coil, and the wall member includes at least one aperture operable to provide thermal communication from the voice coil through the wall member; and a heatsink is coupled to an outer surface of a bobbin and is in thermal communication with the voice coil.

Abstract: Methods and apparatus for producing first and second drive signals from an input signal such that each drive signal is about 180 degrees out of phase with respect to the other; variably altering at least one of the first and second drive signals such that their respective magnitudes may be unbalanced to a varying degree; and producing an output signal from the first and second drive signals such that it includes harmonic distortion when the first and second drive signals are unbalanced.

Abstract: Methods and apparatus contemplate: an output transformer having at least first and second separate primary windings and at least one secondary winding, each winding including a first (in phase) end and a second (out of phase) end; at least first and second active elements, each having at least a pair of power terminals and a control terminal, one power terminal of each active element being coupled to a common node; and a switching circuit operable to change a circuit configuration of the first and second primary windings and the active elements between a class A mode and a class A/B mode.