The EQ-231 offers dual31 ISO center, 1/3 octave constant Qfrequency bands in a single package. While the use of lowtolerance components yields accurate frequency centers.
The graphic section can work at a smooth 6 db/oct or a more aggressive 12db/oct.
In addition to graphic EQ there are input low and high cut 12db/oct filters. These are great for setting the initial boundariesand then using the sliders for better effect.