In the words of Spaceman Effects:

The Equinox is an expansive tone shaping tool borne from a widely acclaimed studio equalizer. The core passive circuit features an abundance of options that have never really been applied to traditional stompbox EQs until now. The low frequency and high cut frequency bands are first order – 6dB per octave filters, while the high boost band is a second order – 12dB per octave filter. With new input and output stages, and revamped frequency ranges, this fantastic design can easily be employed to great effect directly on your pedalboard.