RESO Manual


RESO is a dynamic resonance suppressor that helps you quickly identify and resolve resonances in your audio.

When resonances build up to an excessive level, your music can sound harsh and unpleasant, often masking other elements that you actually want to hear. But, applying broad resonant reduction across your whole mix can take away the character of your audio, and if you apply too much reduction you’ll make the mix sound thin and reduce the punch of your transients. 

RESO helps you identify which specific frequencies have a build-up of energy relative to your whole mix. It also guides you on how much reduction is needed to dynamically resolve the resonance without overdoing it. The high-quality filters deliver mastering-grade transparency, with automatic Q optimization to give you the most musical results.

There simply isn’t a faster or more effective way to musically resolve resonant issues in your mix. 


RESO can be used to fix the resonances of any channel in your mix, whether it’s a vocal, a synth, percussion, busses, or your mastering chain. 

RESO plugin can be used to soothe the resonances of vocals, synths, drums, grouped stems and mixing/mastering chains.

Once you’ve loaded up an instance of RESO, play your audio and click ‘Calculate Targets’. RESO will then analyze your audio, find the most resonant frequencies, and give you ‘Target Nodes’ showing how much reduction is suggested to transparently resolve the resonance. 

RESO samples the input spectrum multiple times per second and creates a record of maximum frequency magnitudes that are statistically significantly higher than their neighbouring frequencies.

Automatically locate resonances in your audio using RESO.

You can now click ‘Engage Targets’ or click the targets one by one to engage the nodes and initiate processing. From this starting point, you can then adjust the nodes to suit the music and your taste. Creating another node is as easy as double-clicking anywhere on the interface.  

Quickly fix resonances when mixing using RESO


RESO displays a frequency analyzer with the peak scale on the right-hand side. To keep the interface as clean as possible, you interact directly with the frequency analyzer. 

By default, the display shows pre, post, and max peaks across the frequency spectrum. Listen to your audio and use the frequency display to help you locate any frequencies that sound disproportionately resonant in the context of the other frequencies.

Double click anywhere within the main window to create a node to initiate the dynamic reduction of a frequency. Position the node at the peak level at which you want the resonance suppression to start. 

Create a node to being dynamic resonance suppression

We recommend aiming around the real-time ‘pre’ frequency display for transparent resonance control, and then dragging the node down from there for a more significant reduction. 

RESO uses a soft knee to reduce the amplitude of the frequency as it approaches and surpasses the node. 

Click reset to refresh the white line max peak analysis to get a clear visual of how the processing affects your sound.


Each node can be moved freely around the spectrum. To lock the frequency, hold control before moving the node. This will allow you to maintain the set frequency and vertically adjust the amount of dynamic reduction.  

Click and control will lock the frequency of a node

To lock the peak reduction and adjust the frequency, hold ‘shift’ before moving the node horizontally. 

When you create a node, the Q is automatically optimized to sound great for that frequency. If you move the node around, it will automatically update the Q. You can scroll whilst hovering over a node to adjust the Q to suit the music and your preference. 

The Q range is limited based on the frequency. Lower frequencies have a lower (i.e. 5-7Q) and smaller range whilst higher frequencies have a higher (i.e 25-40Q) and larger range. This keeps ensures the filters work cleanly with the affected frequencies.

Scroll whilst hovering over a node to adjust the Q

You can click and drag to select multiple nodes and adjust them simultaneously. 

Multi-select nodes in RESO.

Hover over a node to reveal the solo, bypass, and delete controls.



The A/B button allows you to quickly switch between two different states of the plug-in. This enables you to try a different approach to your audio to see what works best.

A/B control in RESO

The arrow above the A/B button copies the active state to the inactive state. This allows you to keep the current settings of the plugin in the inactive state and make a few adjustments in the active state to see if you can improve the sound. You can then jump between A/B to see which you prefer.


RESO makes locating resonances by ear easier than ever. A classic way to identify resonances is to create an EQ boost with a thin Q bandwidth and sweep around the frequency spectrum and listen for a problematic frequency that jumps out at you.

When the frequency sweeping icon in RESO is activated, your mouse position will determine which frequency is being boosted. You can then engage nodes on the fly when you identify a resonance.

Frequency sweep to identify resonances.

Hold ‘control’ to toggle the frequency sweeping on and off.

(Note: Almost every frequency will sound unpleasant when boosted with a high Q. Use this feature with caution to pick out disproportionately resonant frequencies). 


As with all things in audio, you want to be sure all processing has a positive effect on the sound of the mix and is getting you closer to your desired sound. You can click the Delta button to solo what RESO is removing from your mix. 

Delta control in RESO to hear what processing is being applied to your sound. 


The bypass button will let you preview the before and after results of the processing.

Bypass button in RESO


When you create a node, it’s at a specific peak level that relates to the input volume of the signal. If the input gain changes (due to changes in your processing chain or gain of the audio), then the amount of processing applied by RESO will also change. This would also be the case for any compressors in your chain that are triggered by a threshold. 

We included a quick fix for this in RESO. You can click the ‘link button’ which will allow you to adjust the input gain by any amount, and it will automatically adjust the output gain to maintain the exact same volume. 

Inout and output gain linking for gain stage control.

You could use this like a wet/dry slider. Start by clicking the input and output gain link button. Then push the input gain up for more resonance reduction and lower the input gain for less resonance reduction. 

Super-Transparent Filters

There is a balance in filter design between various factors including CPU use, phase distortion, transient smearing and pre or post-ringing.

We have spent a great deal of time researching and developing what we believe to be the most perfect achievable filter for the purpose of resonance removal. RESO's filters have a very near-linear response with far less phase distortion than equivalent minimum phase filters.

Also, for higher Q values, RESO's filters produce much less pre or post-ringing of transients than comparable market leading filters.

In the plot below we show a step response of RESO compared to a market leading filter. The step response can be thought of as how the filters react to a transient such as a snare drum.

RESO Filter performance plot

The plot shows clearly that RESO's filter's add only a very small amount of pre and post-ringing to the step signal, indicating that transients in a mix or channel will be left virtually unharmed in terms of ringing and smearing.

Overall these factors also contribute to much less total harmonic distortion, which again ensures the maximum clarity and transparency of RESO.


We hope RESO helps you identify and resolve the resonances in your audio so you can release the best-sounding music you’ve ever created. We’re here to help if you run into any problems or have any questions. Contact Support.