The equalizer is under the Sound option in the Settings menu. Using the remote, press the Settings button (located directly below the Netflix button). Scroll to the bottom icon on the right side of the screen (it's gray with 3 dots) for All Settings. Click ok. Scroll down to Sound; then click the right arrow to move to the sound options. Make sure Smart Sound Mode is in the off position; otherwise, you will not be able to adjust the Equaluzer. Scroll down to Sound Mode Settings and click the ok button. Scroll down to Equalizer and press the ok button. Now, using the arrow and ok buttons on the remote, adjust the Equalizer to your personal preference. When finished, press the Exit key on the remote.
As a side note, using Smart Sound Mode will override any manual settings you have selected; however, it will not change your Settings. If you turn off Smart Sound Mode, it reverts back to the manual settings you selected.