Electrical audio signal processing systems and devices – With amplifier
Reexamination Certificate
2005-05-19
2010-02-02
Mei, Xu (Department: 2614)
Electrical audio signal processing systems and devices
With amplifier
C398S140000, C359S337130, C359S337400
Reexamination Certificate
active
07657041
ABSTRACT:
A fiber optical audio preamplifier receives audio signals from an audio source, amplifies the audio signals, and transfers the signals to a power amplifier. The fiber optical audio preamplifier has at least one first signal converter. Each first signal converter acquires one audio signal from one audio source and converts the audio signal to a modulated light signal. At least one fiber optic volume control device that includes a variable optical attenuator that is connected to receive the modulated light signal. A control signal for sets an attenuation factor of the variable optical attenuator for attenuating the modulated light signal to control volume of the audio signal. One second signal converter is in communication with each fiber optic volume control device to receive the attenuated modulated light signal and demodulate the attenuated modulated light signal to recover the audio signal for transmission to the power amplifier.
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Ackerman Stephen B.
Knowles Billy
Mei Xu
Saile Ackerman LLC
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