Abstract: A method and apparatus are provided for reducing reaction forces in loudspeakers. The method includes providing, from a power source (312) connected to a loudspeaker (304), a current to the loudspeaker. The method also includes measuring, using a current sense resistance (308) connected in series to the loudspeaker, the current through the loudspeaker. The method further includes providing, using a voltage-controlled source (310) connected in series to the loudspeaker, a current substantially proportional to the measured current through the loudspeaker to an actuator (306), wherein the actuator is connected in series to the loudspeaker.

Abstract: A method for improving the effective signal-to-noise ratio (“SNR”) of an analog to digital converter (“ADC”) for active loudspeakers uses the two available channels of a stereo ADC to separately process the low- and high-frequency components of an audio signal. Because the power spectral density of music approximates a pink noise spectrum, the high-frequency component of the signal has peak levels low enough to avoid exceeding the maximum ADC input level. The audio signal is analog high-pass filtered and the resulting high-frequency signal component is sent directly to a first ADC channel without attenuation. The remaining low-frequency component is attenuated and sent to a second ADC channel. The digital signals are processed, converted back to analog, amplified, and reproduced by loudspeaker drivers. Noise and distortion at low frequencies is less audible than higher frequencies, so the improved SNR at higher frequencies yields a significant practical improvement in audio fidelity.

Abstract: A method for improving the effective signal-to-noise ratio (“SNR”) of an analog to digital converter (“ADC”) for active loudspeakers uses the two available channels of a stereo ADC to separately process the low- and high-frequency components of an audio signal. Because the power spectral density of music approximates a pink noise spectrum, the high-frequency component of the signal has peak levels low enough to avoid exceeding the maximum ADC input level. The audio signal is analog high-pass filtered and the resulting high-frequency signal component is sent directly to a first ADC channel without attenuation. The remaining low-frequency component is attenuated and sent to a second ADC channel. The digital signals are processed, converted back to analog, amplified, and reproduced by loudspeaker drivers. Noise and distortion at low frequencies is less audible than higher frequencies, so the improved SNR at higher frequencies yields a significant practical improvement in audio fidelity.

Abstract: A method for improving the effective signal-to-noise ratio (“SNR”) of an analog to digital converter (“ADC”) for active loudspeakers uses the two available channels of a stereo ADC to separately process the low- and high-frequency components of an audio signal. Because the power spectral density of music approximates a pink noise spectrum, the high-frequency component of the signal has peak levels low enough to avoid exceeding the maximum ADC input level. The audio signal is analog high-pass filtered and the resulting high-frequency signal component is sent directly to a first ADC channel without attenuation. The remaining low-frequency component is attenuated and sent to a second ADC channel. The digital signals are processed, converted back to analog, amplified, and reproduced by loudspeaker drivers. Noise and distortion at low frequencies is less audible than higher frequencies, so the improved SNR at higher frequencies yields a significant practical improvement in audio fidelity.

Abstract: A method for improving the effective signal-to-noise ratio (“SNR”) of an analog to digital converter (“ADC”) for active loudspeakers uses the two available channels of a stereo ADC to separately process the low- and high-frequency components of an audio signal. Because the power spectral density of music approximates a pink noise spectrum, the high-frequency component of the signal has peak levels low enough to avoid exceeding the maximum ADC input level. The audio signal is analog high-pass filtered and the resulting high-frequency signal component is sent directly to a first ADC channel without attenuation. The remaining low-frequency component is attenuated and sent to a second ADC channel. The digital signals are processed, converted back to analog, amplified, and reproduced by loudspeaker drivers. Noise and distortion at low frequencies is less audible than higher frequencies, so the improved SNR at higher frequencies yields a significant practical improvement in audio fidelity.

Abstract: Structures with integrally formed property enhancing fill material, and a method for fabricating such structures, are presented. In one or more embodiments, the method of the present invention includes forming the structural members of a structure out of a powdered material using selective laser sintering (“SLS”) such that the structural members of the structure enclose one or more internal cavities. In one or more embodiments, the structure is provided with an internal passage that forms a direct connection between first and second external apertures. One or more internal apertures and or passages form a passage from one or more of the internal cavities to the internal passage connecting the external apertures.

Abstract: Structures with integrally formed property enhancing fill material, and a method for fabricating such structures, are presented. In one or more embodiments, the method of the present invention includes forming the structural members of a structure out of a powdered material using selective laser sintering (“SLS”) such that the structural members of the structure enclose one or more internal cavities. In one or more embodiments, the structure is provided with an internal passage that forms a direct connection between first and second external apertures. One or more internal apertures and or passages form a passage from one or more of the internal cavities to the internal passage connecting the external apertures.