The API 550A is one of the most beloved console EQs of all time, and if you've got a 500 Series frame in your studio, you can find out why for yourself. This iconic discrete three-band is just what the doctor ordered for tracking and mixing all kinds of sources, from guitars to drums to vocals and back again. Each band offers seven selectable center frequencies with a shelf switch on the outer bands, and the bandwidth tightens up as you boost or cut, allowing you to zone in on a specific section of the sound. With +30dB of output headroom, the 550A can boost the daylights out of the low-end on a kick drum without sweating.