3 band equalizer

Description: This is a simple three-band graphic equalizer circuit built using a single operational amplifier IC, the LF351, along with several passive components. The component values in this circuit are not highly critical and can be substituted with the nearest available values with minimal impact on performance. This feature allows for easy assembly using components from existing supplies. The operational amplifier LF351 is configured to operate across three frequency ranges: high, medium, and low. The circuit is designed to provide a +/-20 dB boost or attenuation at frequencies of 50 Hz, 1 kHz, and 10 kHz by adjusting the potentiometers R3, R6, and R9. The maximum amplification for any of these frequency bands, when supplied with the maximum voltage, is 20 dB. The LF351 is configured as an inverting amplifier, and its response to the specified frequencies can be modified by varying the settings of the potentiometers R3, R6, and R9.

The simple three-band graphic equalizer circuit employs the LF351 operational amplifier, which is known for its low noise and high slew rate characteristics, making it suitable for audio applications. The circuit configuration consists of three distinct bands, each corresponding to a specific frequency range. The inverting amplifier configuration allows for precise control over the gain applied to each frequency band.

The use of potentiometers R3, R6, and R9 enables users to adjust the gain for the low (50 Hz), mid (1 kHz), and high (10 kHz) frequency bands. By turning these potentiometers, the user can achieve a desired tonal balance, enhancing or attenuating specific frequencies as needed for various audio applications. The circuit can be powered by a dual supply, typically +/-15V, to ensure that the op-amp operates within its optimal range.

The passive components, such as resistors and capacitors, are selected to set the frequency response of the equalizer. The values of these components can be adjusted to fine-tune the performance of the equalizer, allowing for flexibility in design and implementation. This adaptability makes the circuit a practical choice for hobbyists and professionals alike, as it can be easily constructed from commonly available components.

Overall, this simple three-band graphic equalizer circuit represents an effective solution for audio signal processing, allowing for tailored sound adjustments in various applications, including home audio systems, musical instruments, and recording equipment.This is a simple 3 band graphic equalizer circuit that`s built by a single op amp IC LF351 IC and few passive components. The component values of this circuit are not very critical and can be replaced with nearest values with a little loss on the performance.

This is feature make it easy to be assembled from your junk box. This is a figure of the circuit; How is the simple 3 band graphic equalizer work The op amp LF351 is wired to operate in three frequency ranges-high, medium and low. The circuit is designed such that the circuit produces +/-20 dB boost or attenuation for 50Hz, 1KHz and 10Khz by varying POT`s R3, R6 and R9.

The maximum amplification for any of these bands at maximum supply voltage is 20dB. The op amp LF 351 is wired as an inverting amplifier whose response to frequencies 50Hz, 1Khz and 10KHz can be varied by adjusting POT`s R3, R6 and R9.