RESO review
A focused plugin for finding and dynamically reducing harsh resonances.
Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026
RESO is an audio plugin for producers and engineers who need to identify and reduce harsh, ringing, or boxy resonances. It can be inserted on vocals, instruments, buses, or full mixes during mixing and mastering. The plugin is available for macOS and Windows hosts in AU, VST 3, and AAX formats, making it suited to common production and mastering workflows where resonance control is a specific requirement.
RESO’s main strength is the depth of its resonance-focused processing. Automatic resonance analysis identifies problematic frequencies, while dynamic suppression reduces them without relying on a constant EQ cut. Frequency Sweep helps locate resonances, and Calculate Targets determines target frequencies for processing. Adjustable Q provides control over the suppression nodes, while mastering-grade filters support use beyond individual tracks. This gives engineers a focused set of tools for shaping harsh or congested material while retaining the plugin’s narrow purpose.
The product is sold as a single paid plan named RESO, with no free plan. Its platform fit is defined by host compatibility rather than a wider ecosystem: it functions as a plugin for supported macOS and Windows audio hosts and is offered in AU, VST 3, and AAX formats. Choose RESO if automatic resonance analysis and dynamic suppression are central to your workflow, especially across vocals, instruments, buses, and full mixes. Choose another tool if you need a broader mixing suite, a wider range of processors, or a product built around features beyond resonance management.
RESO pros and cons
- Where it wins
- Analyzes and suppresses harsh resonances dynamically
- Works on vocals, instruments, buses, and full mixes
- Includes Frequency Sweep and Calculate Targets tools
- Where it doesn't
- Narrowly focused on resonance control
- Paid product with no free plan
- Requires a compatible macOS or Windows host
RESO fact sheet, pricing and score →
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