Previously I shared 40 led vu meter circuit using Audio Spectrum Analyzer, Spectrum Analyzer circuit 10 channels (32Hz, 1kHz, 2kHz, 4kHz, 8kHz, 16kHz, 64Hz, 125Hz, 250Hz, 500Hz) on a total of 400 LED’s Spectrum Analyzer circuit 12v DC voltage works with all LEDs illuminated power draws 7.5 amps LM324 op amp used for all integrated control card and vu meter card belonging to the scheme eagle pcb files there .
Main board: Powered by 12V, current is cca 10-15mA To “Stereo input” is connected computer, mp3player, or anything audio source. Outputs from bandpass are signed appropriate frequency.This outputs are connected to “inputs” on VU-meters board. Resistor R5 is main volume to all filters. Output level voltage can be trimmed by trimme on output (R13, R21,…), if that was not enough, just put one resistor between filter output and VU-meter board. Deceleration time of LED column depends on output capacitor (C10,C14,..) you can modified this time, when you change this capacitor(lower value, shorter time to fade down). All resistors are on 0,25W. All capacitors on min. 16V.
VU-meter: Powered by same 12V as main board, current is in peak 750mA. All resistors are on 0,25W. All capacitors on min. 16V. All device peak current: 7,6A.