AAY-Audio aQ-31 was developed to be a traditional 31- band graphic equalizer plug-in with clean sound in VST plug-in format for Windows computers.

aQ-31 have switchable gain range +/- 6/12/18/24 dB per band and Q-knob for adjust the filter's bandwidth. This knob gives you possibility to make the equalizing curve more glossy or sharp.

aQ-31 was released in four variations:

- aQ-31m - mono

- aQ-31s - stereo

- aQ-31lr - stereo dual channel

- aQ-31ms - stereo with mid-side dual channel