low noise equalizer

This circuit uses an OP-270 op amp to form a 5-band low noise graphic equalizer. It provides 15dB of boost or cut over the 5-band range. Signal-to-noise ratio over a 20kHz bandwidth is better than 100dB refered to 3v rms input. Larger inductors can be replaced by active inductors but this reduces the signal-to-noise ratio.

As shown, the circuit can't achieve +/- 15 dB control.