Abstract: A Bi-Directional and Adjustable Current Source (“BACS”) for providing an input voltage to a mute/standby control pin of a power stage integrated circuit (“IC”) of an amplifier input with a voltage signal that is linear, where an output of the BACS and the input to the control pin are shunted with a capacitor, is described. The BACS may include a first switch in signal communication with a high voltage reference and a first current source in signal communication with the first switch. The BACS may also include a second switch in signal communication with a low voltage reference and a second current source in signal communication with the second switch. The BACS may further include a directional current element in signal communication with both the first current source, the second current source, the output of the BACS, the input to the control pin, and the capacitor, where the directional current element is configured to prevent current flow from the output BACS to the first current source.

Abstract: This invention provides a system capable of delivering recorded music pieces to users and empowering the users with control features allowing for customization of the music. Recorded music pieces may be stored and recalled when selected by a user. Each musical piece may include one or more music modules corresponding to one or more musical instruments of The piece. Through a selection menu, the user may select one or more of the modules for inclusion in a customized version of The selected recorded music piece. The user may further adjust the pitch and/or tempo of the musical piece. Once customized by the user, the recorded musical piece may be integrated with sounds created by the user performing a selected musical instrument or instruments. The user may also select predefined special effect setup information module(s) that may be loaded into the signal processor capable of emulating the sonic characteristics of the recording of the recorded music piece.

Abstract: A transducer includes a supporting frame, a motor assembly providing a magnetic field across an air gap, a coil former supporting a voice coil in the magnetic field, a diaphragm attached to the coil former and coupled by a surround at its outer perimeter to the frame, and a spider having an inner perimeter coupled to the coil former and an outer perimeter coupled to at least one of the frame and motor assembly. The spider includes a plurality of rolls. The roll next adjacent the inner perimeter may have a first height. The roll next adjacent the outer perimeter may have a second height less than the first height. The surround may include a plurality of rolls. The roll next adjacent the diaphragm may have a third height, and the roll next adjacent the frame a fourth height less than the third height.