This complete high quality, low noise 5-BAND GRAPHIC EQUALIZER circuit is based around Monolithic Linear integrated circuit LA3600 manufactured by SANYO. This circuit is very easy to build and has good Quality. You can use it with Portable component stereos, tape-recorders, radio-cassette recorders, car stereos etc...
It is On-chip one operational amplifier. 5-band graphic equalizer for one channel can be formed easily by externally connecting capacitors and variable resistors which fix fo (resonance frequency). Series connection of two LA3600�s makes multiband (6 to 10 bands) available. It is Highly stable to capacitive load. Maximum supply voltage VCC max 20V must not be exceeded. The operating voltage is in the range of 5 to 15V. Application of power with the pin-to-pin spaces shorted causes breakdown or deterioration of the IC to occur. When mounting the IC on the board or applying power, make sure that the pin-to-pin spaces are not shorted with solder, etc.
Source: Electronics Lab