The AQ550 emulates the punchy, clear low-frequency response and precise imaging characteristic of iconic American equalizers from the late 1960s. Its design captures the essence of these classic EQs while integrating modern digital flexibility, making it suitable for a wide range of audio production tasks. The equalizer delivers three bands of classic tonal shaping, each offering multiple frequency centers and up to 15 dB of boost or cut, with selectable shelf or peak modes on the low and high bands.

A standout feature of the AQ550 is its use of Proportional Q, an intuitive approach to bandwidth control that automatically adjusts the filter width based on the gain setting. This minimizes the phase-shift artifacts that are common in many equalizers, resulting in a more transparent sound. The EQ can be applied in stereo, mid, or side modes, providing enhanced control over the stereo image. Additionally, a band-pass filter can be independently inserted, expanding creative possibilities without affecting other EQ settings.

Beyond replicating vintage analog character, the AQ550 offers options to bypass analog saturation for a cleaner digital sound. Its user interface includes convenient features such as quick reset to default values and adjustable control sensitivity for precise adjustments. The plugin seamlessly blends the warmth and musicality of classic analog equalizers with the precision and flexibility required in modern mixing and mastering workflows.