Designing Audio Frequency Amplitude Indicator
Yunian Gu · Journal of Nantong Vocational College · 2011
The system uses the input amplifier composed by OP07 to amplify the input audio signal,and then the audio signal will be divided to ten band frequency by ten band-pass filters within 50Hz～10 KHz.The signal after each band-pass filter will control a group of LED independently,and the LED number of each band represents the amplitude of the signal.The test results show that the number and brightness of the LED lights controlled by ten band frequeney is accurate and can meet the design requirements.