How to Fix Vocal Resonances

Here's a common scenario: you're putting the finishing touches on a hard-earned mix, but you can't seem to get the vocal to sit right. It's almost like there's a rogue frequency lurking in the track somewhere.

There's a name for this phenomenon: unwanted resonances. Resonances are maddening; they cause listening fatigue, make your effects processors go haywire, and steal headroom.

Simply put, unwanted resonances make your vocal track — and your entire mix — sound bad. 

Our RESO dynamic resonance suppressor plug-in offers an easy, powerful solution for ridding your tracks of unwanted resonant frequencies. In this post, we'll explore what resonances are and how RESO can get them out of your life — forever.

How to Fix Vocal Resonances

What's a Resonance?

Before we delve into how to get rid of unwanted resonances, we should first explain what resonance is.

According to  Fundamentals of Physics, resonance is "the phenomenon of increased amplitude that occurs when the frequency of a periodically applied force is equal or close to a natural frequency of the system on which it acts."

In plain English, a resonance is when a created frequency interacts with the natural frequency of your room, playback system, or something within your mix itself. You'll perceive the resonance as a runaway vibration, such as feedback, or a buildup of a specific frequency or set of frequencies. 

Here's a video showing how resonances can sound... (and how RESO fixes them)

If your room or playback system are the cause of the unwanted resonances, you'll need to solve those problems physically with decoupling and acoustic treatment. But, if the issue is contained within your mix, you'll need to perform a bit of surgical correction.

Common Types of Resonances

Low-frequency Resonance (Hum)

If there's an unwelcome hum-like sound in the lower end of your track's frequency spectrum, this is the result of low-frequency resonance. This type of hum is an absolute headroom destroyer, and it will make your mixes sound weak and quiet, regardless of what volume you play it back at.

Moreover, when you increase the gain, the hum gets even louder! If you want a loud, punchy mix, it's critical that you resolve any low-frequency resonances.

Low-frequency Resonance (Hum)

High-frequency Resonance (Notch Frequencies)

Notch frequencies create high-frequency resonances in the 10kHz to 15kHz range. If your tracks are replete with harsh, ringing artifacts, this is why. 

High-frequency resonances will cause instantaneous listening fatigue, and it will make your mix very unpleasant to listen to.

High-frequency Resonance (Notch Frequencies) 

What's RESO?

RESO is a dynamic resonance suppressor that resolves unwanted resonances with just a few mouse clicks — transparently. Transparency is crucial, as applying broad-stroke resonant reduction across your entire mix will cause it to take on a deflated character, rendering it thin and lifeless.

With RESO, you can avoid this sledgehammer approach. It not only helps you identify problem frequencies, but it also guides you on how much reduction is needed to dynamically resolve the resonance without overdoing it. 

What's more, RESO's high-quality filters yield mastering-grade transparency, with automatic Q optimization to give you the most musical results.

Find Your Target — Effortlessly

Identifying resonances with RESO is a breeze. Simply instantiate the plug-in, play back your vocal track, then click the Calculate Targets button.

RESO will analyze your audio, automatically find problem frequencies, then provide you with Target Nodes that show you how much reduction is required for transparent resonance suppression.

RESO's calculations are spot-on, employing advanced algorithms to identify resonant frequencies. This cutting-edge plug-in samples the input spectrum multiple times per second, and it creates a record of maximum frequency magnitudes that are statistically higher than their neighboring frequencies.

Once you've located the unwanted resonances in your vocal track, click the Engage Targets button to initiate processing. You can also click each target one by one to engage the Target Nodes individually. 

From this starting point, you can tweak the Target Nodes to best suit your mix.

Identifying resonances with RESO is a breeze

Target Node: Explained

RESO's Target Nodes are essentially threshold controls, similar to those you'd find on a standard dynamic compressor. When audio exceeds this threshold, it's reduced or attenuated.

Want to create a new Target Node? No problem. It's as easy as double-clicking anywhere on RESO's interface. Simply position the Target Node at the peak level at which you want resonance suppression to start, and you're good to go.

You can move each Target Node anywhere around the frequency spectrum. To lock a frequency, simply hold down your Control key before moving the Target Node.

This will enable you to maintain the set frequency and vertically adjust the amount of dynamic reduction. If you want to lock the peak reduction and adjust the frequency, hold down your Shift key before moving the Target Node horizontally. 

You can also click and drag to select multiple Target Nodes and adjust them simultaneously. Beyond that, hovering over a Target Node will reveal Solo, Bypass, and Delete controls.

RESO's Target Nodes are essentially threshold controls

Automatic Q Ensures the Most Musical Results

Whenever you create a Target Node in RESO, the Q is automatically optimized for the frequency to give you the most musical result. Thus, if you move a Target Node around, it will automatically update the Q.

You can also scroll while hovering over a node to adjust the Q manually to suit your track.

RESO's Q range is limited based on frequency. Lower frequencies possess a smaller range, while higher frequencies have a larger range.

This ensures clean, transparent-sounding filters. 

What's more, RESO's filters boast a near-linear response with negligible phase distortion when compared to equivalent minimum-phase filters. Beyond that, RESO's filter produces much less pre- or post-ringing of transients at higher Q values than comparable market-leading filters.

Automatic Q Ensures the Most Musical Results

Level Out Your Processing with Gain Link

When you create a Target Node in RESO, it's at a specific peak level that relates to your input volume. If the input gain on your vocal track changes due to added plug-ins or other processors, then RESO's processing will increase accordingly.

To compensate for this, RESO has included a "gain link" button that automatically adjusts your output gain if your input gain changes. This will maintain the exact same volume, no matter how you process your vocal track. 

Some users deploy RESO's gain link feature as a wet/dry slider. Start by clicking the input and output gain link button, then push the input gain up for more resonance reduction, or down for less resonance reduction.

Level Out Your Processing with Gain Link

Taking Matters into Your Own Hands

So, what if you want to locate resonances manually by sweeping around and listening for problematic frequencies? RESO takes this into account, enabling you to use the classic sweep-and-listen method, but with superior results.

RESO's interface contains a frequency analyzer, along with a peak scale on its right hand side. This allows you to search for disproportionately high peaks in the visual display, then use the plug-in's Frequency Sweep function to identify resonances that sound unpleasant.

To toggle the Frequency Sweep function on and off, hold down your Control key. When this function is active, your mouse position will determine which frequency is being boosted.

You can then create Target Nodes on the fly by double-clicking your mouse whenever an unwanted resonance jumps out at you. This will initiate dynamic reduction of the problematic frequency. 

You can also combine RESO's Frequency Sweep and Calculate Targets functions. Start by seeking and destroying audible resonances using the Frequency Sweep function, then use Calculate Targets to take out the sneakier ones that are more difficult to detect manually.

ocate resonances manually by sweeping around and listening for problematic frequencies


Whether you're an experienced professional or a bedroom producer, cleaning up resonances is essential for creating great-sounding vocal tracks (and great mixes in general).

Skip this important step in the mix process, and you'll never achieve the loud, punchy, cohesive sound you're striving for. Perform this step incorrectly, and you'll end up with weak, hollow-sounding mixes.

Our RESO plug-in provides you with a fast, easy way to tackle resonances, while also supplying you with convenient features and industry-leading sound.