Soundtheory [Gullfoss] Tutorial 2. Parameters and Application

Author: sleepfreaks

A new type of EQ for any level of user

Soundtheory Gullfoss

This is our second article on Soundtheory‘s [Gullfoss] plugin.
We will take a look at some parameters to achieve our ideal sound.

With it’s detailed sound analysis, you can achieve next level sound quality.
It proves as a fantastic tool for sound control!

[Gullfoss] 2. Parameters and Application

Gullfoss’s parameters


Sound can be effected using the 5 parameters shown above.
It doesn’t contain the usual EQ points found in an EQ, making a new type of EQ.


Gullfoss auto analyzes your audio into 2 main groups:

  • The dominant frequencies making up the sound
  • All other non-dominant frequencies

For example, a kick is pre-dominantly made out of low end frequencies.
Recover/TAME works as shown below:


  • RECOVER: raises non-dominant frequencies
  • TAME: suppresses dominant frequencies

Using these tools, the frequency balance can be smoothed out to create a more balanced track.

An important point is to make the the dominant sound is selected during the mixing process.
This is because using the base material to the fullest extent gives you the best results with this equalizer.

The changes in frequencies can be seen in the display.
In addition, by moving the mouse over a parameter, the meters related to it will be highlighted.



When mastering, if certain frequencies seem off balance, you can use RECOVER and TAME to tweak them.

  • Positive amounts: The closer to 100, the higher the RECOVER effect
  • Negative amounts: The closer to -100, the higher the TAME effect

We recommend making small edits while monitoring sound.



This is used to brighter and add clarity to the sound.
This only is active when RECOVER or TAME is set to an amount other than 0.

  • Positive amounts: The closer to 100, the brighter the sound
  • Negative amounts: The closer to -100, the darker the sound

Even when the BRIGHTEN amount is 0, it is edited slightly through other parameters.
Leave the parameter if you feel the sound is already good, and generally functioning between -15% to +15% is recommended.



This adjusts the frequency balance in retrospect to human hearing.
When raised, the low end frequencies are boosted, and the mid-highs are suppressed.
By lowering it negative, it has the opposite effect (bass lowered, mid-highs raised).

Use this to control your overall sound by genre or preference.

Limit marker


By dragging the left/right limit markers, you can narrow down the span of effected frequencies.
Use it in cases where you don’t want certain frequencies to be effected.

One precaution, is that even with limit markers set, the [BOOST] parameter will still be applied to all frequencies.



This controls the overall volume post equalization.

Short cut key


To return any parameter on Gullfoss to 0%, use

  • Mac: option+click
  • Windows: Alt+click

Use this to check your sound before and after application.

We hope you enjoyed this article.
We tried the plugin out on multiple tracks, and they all turned out very natural and musically edited.

Because of it’s ability to instinctively edit sound, even beginners can get full use out of this product.
A demo version is available, so definitely try it out!

Related link: Soundtheory