this led bar graph contains only three LED s and each LED show the low, mid range and high frequencies according to the audio played, this bargraph can be used in audio amplifiers, the circuit is for a 40w amplifier, connect the circuit in parallel to the speakers and no external power supply is needed........
Step 1: Parts List
1 x red LED ( or any color you like)
1 x Blue LED (or any color you like)
1 x Green LED (or any color you like)
1 x 1uf capacitor (electrolytic) 16v
1 x 3.3uf capacitor 16v
1 x 4.7uf capacitor 25v