The graphic equalizer shown here is based on the IC LA3600 from Sanyo Semiconductors. LA 3600 is a single integrated single Op-amp, 5 band graphic equalizer IC which is very suitable for applications like portable stereo, radio sets, home theater systems, car audio systems etc. The LA3600 can be operated from anything between 5 to 15V DC and is extremely stable to capacitive loads.
In the circuit capacitors C1, C3, C5, C7 and C9 are used to fix the resonance frequency of the corresponding bands. Capacitors C2, C4, C6, C8, C10 and C15 are the input capacitors and increasing the value of these capacitors will increase the low frequency response. Capacitor C13 is a decoupling capacitor and C14 is a power supply filter circuit. C12 is the output capacitor and resistor R6 limits the supply current. Gain of each band can be adjusted by using the corresponding potentiometers R1 to R5.

Circuit diagram.

5 band graphic equaliser circuit


  • Assemble the circuit on a good quality PCB.
  • I used 9V DC for powering the circuit.
  • The power supply must be well regulated and noise free.


  1. dear seetharaman sir,

    what is the output power?
    is the same power level as the input or circuit amplifies the signal?
    what should be the load impedance? and if we connect small speaker then what should be the power rating of speaker and what should be the impedance of speaker.

  2. hello seethraman sir…

    is there any error in this circuit ?
    or everything is correct and nothing is to be any little change?
    is output audio quality good?
    what is the %distortion at output of this circuit?
    and what about efficiency?

    hope you will reply accordingly

    thank you.


    In diagram U have written LA3660 instead LA3600

  4. Vivek verma

    Where do we connect +ve and -ve terminals of power supply along with stereo left and right channel inputs to this circuit,reply soon.

    • Seetharaman

      power supply should be connected to pin no 14 & 16 of ic. the circuit audio in should be the input signal audio out is the frequency corrected output. the circuit shown for on channel only for other channel you have to duplicate the circuit.

  5. Vivek verma

    How we connect stereo input to this circuit?

  6. Could i add this to my homemade tube amp, and take out the LA3600?

  7. sir,kya laptop k display m dvd y t.v. ka output dekh skte h.laptop kharab hogya h.uska display use kese kare pleas btaiye.

  8. seetharaman

    Hi Eric Nice question. Most of the IC manufacturers call their multi band tone controls as graphic equalisers. This will hold good only when following are carried out.
    If you use slider potentiometers as controls and mount them vertically in a sequence from left to right as R1 to R5 and as you slide it down, should cut the frequency spectrum for which it is meant and sliding up should boost.
    Now attach thin knobs to the slider shaft and calibrate the slider center as ‘0’ and slider at the top end as 10 and bottom end as -10. Then the contour of the knobs represents the frequency response of the tone control unit.

  9. what does it mean by “5 Band Graphic Equalizer” please explain