Plugin Boutique has launched a limited time promotion on AIR Music Tech’s OPx-4, offering 80% off on the FM synthesizer instrument for Windows and Mac that offers deep sound design functionality.

OPx-4 is a groundbreaking four operator FM synthesizer with advanced sound editing and an easy-to-understand control layout.

In addition, the system has one of the most profound FM engines ever built with a 4×4 FM matrix that includes tone shaping and filtering and a 32-slot matrix for modulating your FM tones.

The OPx-4 plugin (VST/VST3, AU and AAX) is priced only $29.99 USD instead of $149 USD. The offer is available at Plugin Boutique and from ADSR Sounds until March 27th, 2023.