Abstract: A locking string retainer minimizes undesired movement of instrument strings across the nut of a stringed instrument. When attached to the instrument headstock just behind the nut, the string retainer sets the angle at which the strings contact the nut. The string retainer includes a locking mechanism that is operated by a lever. When the lever is in the unlocked position, the instrument can be tuned and played normally. When the lever is in the locked position, the mechanism allows near zero travel of the strings across the nut, even during aggressive use of a vibrato bar. When the instrument inevitably does go out of tune, the user can easily unlock the string retainer, retune the instrument, and re-lock the retainer.

Abstract: A speaker system includes one or more rotating speakers (or speakers with rotating reflectors) that are synchronized in absolute angular position to another rotating speaker or synchronized to audio effects to generated by a signal processing system driving a stationary or rotary speaker. Knowledge of absolute angular position in a multi-rotor speaker array or signal processing system allows for control of rotary position to accomplish acoustic effects otherwise not possible, such as matched-velocity profiles with differential phase control and motion profiles that are not based on simple rotation.

Abstract: A speaker system includes one or more rotating speakers (or speakers with rotating reflectors) that are synchronized in absolute angular position to another rotating speaker or synchronized to audio effects to generated by a signal processing system driving a stationary or rotary speaker. Knowledge of absolute angular position in a multi-rotor speaker array or signal processing system allows for control of rotary position to accomplish acoustic effects otherwise not possible, such as matched-velocity profiles with differential phase control and motion profiles that are not based on simple rotation.

Abstract: A speaker system includes one or more rotating speakers (or speakers with rotating reflectors) that are synchronized in absolute angular position to another rotating speaker or synchronized to audio effects to generated by a signal processing system driving a stationary or rotary speaker. Knowledge of absolute angular position in a multi-rotor speaker array or signal processing system allows for control of rotary position to accomplish acoustic effects otherwise not possible, such as matched-velocity profiles with differential phase control and motion profiles that are not based on simple rotation.