1. Field of the Invention
The present invention relates to a frequency response detection apparatus, and more specifically to an apparatus for detecting the frequency response of audio signals.
2. Background Information
Apparatuses for detecting frequency response such as the spectrum analyzer, are designed so that the audio band is divided into a plurality of frequency bands, and the signal level is detected for each of the plurality of frequency bands. Such apparatuses are provided with means for dividing the audio signal into a plurality of frequency band signals, means for respectively detecting the frequency band signals, and means for switching and in turn relaying one of the detection output signals. The relayed detection output signal is treated by an A/D (analog-to-digital) conversion process, and then used as a drive input signal of a two-dimensional display means such as an LED (light-emitting diode) display device so that the detected frequency response is displayed as the frequency spectrum.
In the case where the frequency response is detected for each of the audio signals of the L (left) and R (right) channels with this type of frequency response detection apparatus, a circuit having the above described construction is provided separately for each of the left and right channels. Therefore, there inevitably is an increase in number of the circuit elements constituting the apparatus, and cost increases have resulted.
Hence, it is conceivable to detect the frequency response of each of the audio signals of L and R channels by a time-division process in order to use the circuit commonly for the signals of both channels. In this case, however, it is necessary that the frequency response can be surely detected for each of the channels.