Patent ID: 6681019
Filing Date: 2004-01-20
Classification: H04R

Abstract:
A polarity determining circuit for loudspeakers, comprising:a test signal generator which generates either one of a positive-phase signal of a test signal and a negative-phase signal of the test signal, the test signal being delivered to a signal switching device and either one of a left speaker terminal and a right speaker terminal, wherein the test signal generator includes a white noise generator which generates a white noise signal, and a low-pass filter which receives the white noise signal, and which extracts a low-frequency component of the white noise signal and outputs the low-frequency component as the test signal; the signal switching device which, based on a switching operation of a user, selectively outputs either one of the positive-phase signal of the test signal and the negative-phase signal of the test signal as an output signal; and the left and right speaker terminals, wherein the output signal of the signal switching device is output from one of the left and right speaker terminals, and one of the positive-phase and negative-phase signals of the test signal from the test signal generator is constantly output from the other of the left and right speaker terminals.