In 1950, an unassuming audio engineer named Peter J. Baxandall won a $25 dollar watch for an innovative treble & bass circuit design. 64 years later, Goodhertz brings you Tone Control — a powerful EQ based around a simple idea.

Designed with his original circuit in mind, Tone Control refines and expands the classic tone stack, creating a gorgeous, buttery-smooth equalizer with enough versatility for every track in your mix or mastering session.


Primary Controls


N.B. The Linear Phase control affects the Bass shelf filter design.

Bass On/Off

Turns the Bass shelf on/off.

  • Default On

Bass Gain

Amount of Bass boost/cut.

  • Min -15.0dB
  • Max 15.0dB
  • Default 0.0dB

Bass Freq

Center frequency of the Bass shelf.

  • Min 20Hz
  • Max 2.00kHz
  • Default 200Hz

Bass Slope

Varies the steepness of the Bass shelves slope.

At 0%, the transition band is very smooth, gradually transitioning across several octaves. At 100%, the shelf quickly transitions from 0 dB to its maximum boost/cut.

  • Min 0%
  • Max 100%
  • Default 50%


N.B. The Linear Phase control affects the Treble shelf filter design.

Treble On/Off

Turns the Treble shelf on/off.

  • Default On

Treble Gain

Amount of Treble boost/cut.

  • Min -15.0dB
  • Max 15.0dB
  • Default 0.0dB

Treble Freq

Center frequency of the Treble shelf.

  • Min 200Hz
  • Max 20.0kHz
  • Default 5.00kHz

Treble Slope

Varies the steepness of the Treble shelf’s slope. Comparable to the Bass Slope control.

  • Min 0%
  • Max 100%
  • Default 50%

Low Cut

Tone Control’s Low Cut filter allows careful adjustment of the lowest bass content in a signal.

Use the controls in this module to cut out or reduce unwanted low frequency information, infrasonic sounds, popping p’s, plosives, rumble, or DC offset. By removing unwanted low end, clarity, definition, and headroom can often be increased in a mix.

Low Cut On/Off

Turns the Low Cut on/off.

  • Default Off

Low Cut Freq

Center frequency of the Low Cut.

  • Min 10Hz
  • Max 20.0kHz
  • Default 20Hz

Low Cut Slope

Varies the steepness of the Low Cut continuously from 6.0dB/Oct to 48.0dB/Oct.

Use a steep slope when you want to completely eliminate all information below the Low Cut Freq. Use a gentle slope to gradually roll off low end over several octaves.

  • Min 6.0dB/Oct
  • Max 48.0dB/Oct
  • Default 24.0dB/Oct

High Cut

Tone Control’s High Cut allows careful adjustment of the high end content in a signal.

Use the controls in this module to cut out or reduce unwanted high frequency information, CRT whine, or ultrasonic sounds.

High Cut On/Off

Turns the High Cut on/off.

  • Default Off

High Cut Freq

Center frequency of the High Cut.

  • Min 10Hz
  • Max 24.0kHz
  • Default 20.0kHz

High Cut Slope

Varies the steepness of the High Cut continuously from 6.0dB/Oct to 48.0dB/Oct.

Use a steep slope when you want to completely eliminate all information above the High Cut Freq. Use a gentle slope to gradually roll off high end over several octaves.

  • Min 6.0dB/Oct
  • Max 48.0dB/Oct
  • Default 24.0dB/Oct


Master Air

Tone Control‘s Air filter enables careful refinement of the highest treble content, often referred to as the “air band.” Completely unique to Tone Control, Master Air tone shaping is most obvious above 10kHz, but it does have a perceivable impact across the entire frequency spectrum, which is why we chose the include it in the Master section.

  • The Linear Phase control affects the Master Air filter design.
  • Use the Master Air to control how upfront or forward certain elements sit in a mix. At -100%, sounds are pushed back in the mix, at +100% sounds appear closer and more detailed (often great on a lead vocal).
  • The amount of Air also has a big impact on how modern or vintage things feel. Thus Master Air can also be used as a type of old/new control, where -100% is older and duller, +100% is new and shiny.
  • Min -100%
  • Max 100%
  • Default 0%

Master Mix

Global Tone Control mix.

At 200%, the Bass Gain, Treble Gain, Master Air settings are effectively doubled.

The Master Mix does not affect the Low Cut or High Cut.

  • Min -200%
  • Max 200%
  • Default 100%

Master Gain

Master Tone Control gain.

Master Gain includes a level meter embedded in the slider. This meter shows the peak level of the output signal after Tone Control’s processing.

If the signal peak exceeds or equals 0.0dB the meter color turns red, indicating that clipping could occur. Tone Control will never clip internally, due to its double-precision floating-point processing, but the signal might be clipped at a later stage (by the host/DAW or DAC).

  • Min -96.0dB
  • Max 12.0dB
  • Default 0.0dB

Master On/Off

Bypasses Tone Control’s processing.

We recommend using the Master On/Off instead of your DAW’s plugin bypass to avoid digital artifacts.

  • Default On

Advanced Controls

The Advanced section offers more precise control and fine adjustment options.

To access Tone Control’s advanced controls, click the ••• icon in the sidebar.


Processing Mode Listen

Solos the the signal being processed (as specified by Processing Mode).

  • Default Off

Processing Mode

Processing Mode allows Tone Control’s processing to be applied only to a specific channel. All other channels are passed through the plugin unaffected.

  • Default Stereo

Linear Phase

The Linear Phase control allows continuous variation between minimum phase and linear phase equalization.

At 0%, Tone Control‘s Bass, Treble, & Master Air filters are all minimum phase. At 100%, they are fully linear phase.

The choice of linear phase or minimum phase equalization — or anything in between — is highly subjective, but here are some key differences:

Linear Phase
  • Perfect, linear phase response
  • High latency
  • Both pre- & post-ring
  • “Digital”
  • Often sounds gorgeous & three dimensional
Minimum Phase
  • Some phase deviation
  • Zero latency
  • Post-ring only
  • More “analog-like”
  • Funkier

Tone Control has a handy impulse response visualization to help show what’s going on with the impulse response of the equalizer for various settings, and, most importantly, how the Linear Phase control affects the impulse response & the decay of the filter.

  • HQ Mode must be turned On to use Linear Phase.
  • Linear Phase only affects the Bass, Treble, & Master Air filters. It does not affect Tone Control‘s Low Cut or High Cut filters.
  • Min 0%
  • Max 100%
  • Default 0%

HQ Mode

HQ Mode is our no-holds-barred processing mode where super high quality audio is given priority over CPU usage.

When HQ Mode is turned On, Tone Control uses a higher precision algorithm, providing better spectral resolution at the expense of some added latency (~50 ms) and higher CPU usage.

We recommend using HQ Mode when you need the highest possible quality and don’t mind 2-4x higher CPU usage. An important lead instrument, vocal, or a mastering session is a great place for HQ Mode.

HQ Mode will require more CPU resources and result in a slightly higher processing delay (latency). To ensure proper delay compensation in your host/DAW, automating HQ Mode is not recommended.

  • Default Off


Supported Channel Configurations

Input Channel # Output Channel #
1 1
1 2
2 2


Annlie Huang / Chris Conover / Diana Zheng / Jack Stratton / Nick Nagurka / TaeHo Park


Devin Kerr / Rob Stenson / Jasper Duba / Noah Dayan


TaeHo Park / Tiago Frúgoli / Gustavo Guzmán / Reda Kermach / Noah Dayan

About Goodhertz Plugins

User Interface

Goodhertz plugins are made to be workhorse tools that sound amazing. We’ve put a lot of thought and care into the audio quality and plugin usability, and for that reason, we’ve opted for simple and direct controls & interfaces that don’t rely on photorealistic knobs or ornamental screw heads to communicate their meaning.

We’ve also decided to only include meters and graphs when we feel they will directly lead to a better sonic result. Meters/graphs can consume significant CPU resources, and we firmly believe that if it sounds good, it is good.

Our meters can be manually enabled or disabled via the “Enable Metering” User Preference.

Keyboard Shortcuts

Action Keyboard Shortcut
Enter New Parameter Value Once you’ve tapped or double-tapped a control, type in a value, then hit Enter, Return, or Tab
Increment Parameter Value or arrow keys
Decrement Parameter Value or arrow keys
Jump to Next Parameter Tab
Jump to Previous Parameter Shift + Tab or ` (backtick)
Escape Parameter Focus / Close any Open Drawers Esc
Toggle A/B A (N.B. For this to work, you must have a control selected.)
Shift A to B / Shift B to A Shift + A — this “shifts” the current settings to the opposite A/B state; i.e. if you’re on the A state, hitting Shift+A will copy those settings to the B state. (N.B. For this to work, you must have a control selected.)

Right-Click Actions

Action Instruction
Reset Control to Default Right-Click & select “Reset [control] to Default”
Read about Control in Manual Right-Click & select “Read about [control]”
Lock a control when Switching Presets Right-Click & select “Lock [control] When Switching Presets”
Copy all current plugin settings Right-Click & select “Copy all settings as URL to Clipboard”
Paste all plugin settings Right-Click & select “Paste all settings from Clipboard”
Reset all plugin settings to default Right-Click & select “Reset all settings to default”
Go to the plugin’s product page Right-Click & select “Goodhertz [plugin name]”

Right-Click Preferences

Action Explanation
Language Switch the display language of text elements in Goodhertz plugins. We currently support the following languages: English, Spanish, Portuguese, French, Japanese, Korean, Chinese (Simplified), Chinese (Traditional), and Arabic.
Always Open Advanced Pane By default, this is Off — i.e. when the plugins open, they do not show you the advanced controls available by hitting the ••• button in the sidebar. If you’d like to always see the advanced controls, enable this preference.
Dark Mode Allows you to choose the color palette used for displaying the interface. If you prefer the look of dark colors (or work in a darker environment) enable this option. The Auto option will automatically adjust the color scheme depending on the system preferences of your machine (Mac only).
Enable Metering By default, this is On — i.e. in normal operation, all audio meters and visualizations available in Goodhertz plugins are enabled and running. If you’d like to turn them off and disable all metering and visualization, deselect this option. And to turn them back on, simply reselect it. N.B. If you’re struggling to use a large number of Goodhertz plugins on an older processor with an integrated GPU, sometimes disabling metering can help.
Enable Scroll Input By default, all Goodhertz sliders can be scrolled in addition to dragged. If you find this behavior unnecessary, deselect this option and no scrolling events will be used to control Goodhertz sliders.
Require Double-Click for Keyboard Focus By default, you can get keyboard focus on any Goodhertz control with a single click. Enable this option to ensure keyboard focus only occurs on double clicks.
Window Size Enlarge or shrink the Goodhertz plugin window by selecting an option here. This will save your preference for all instances of this plugin.

Mouse Modifiers

Action Combination (Mac) Combination (Windows)
Reset Parameter to Default Value Option + Click Alt + Click
Move Control with Coarse Precision Shift + Drag Shift + Drag
Move Control with Fine Precision Command + Drag Ctrl + Drag
Move Control with Normal Precision Drag Drag


Unintentional digital clicks and pops are the worst. They happen for lots of reasons and often end up wasting your time with needless revisions or mastering surgery. When they go unnoticed, they can make their way onto commercial albums and releases.

Plugin automation is a common cause of clicks and pops. Sweeping an EQ band, changing a delay setting, and even automating a plugin bypass can cause digital artifacts if poorly handled.

This is not true for Goodhertz plugins. Any parameter in a Goodhertz plugin, even on/off switches, can be automated freely and smoothly without clicks, pops, or zipper noises (unless otherwise noted). You can push them, pull them, LFO them — whatever you do, they’ll handle it gracefully.

Since our Master On/Off controls won’t create artifacts, we recommend that you use them rather than your DAW-supplied plugin bypass if you want to disable plugin processing.

Plugin Settings

Goodhertz plugin settings can be copied and pasted as text urls, which look like this:

To copy and paste, right click anywhere on the plugin interface and select either the copy or the paste option.

E.g. If you paste “” into Vulf Compressor it will recall the settings associated with that url. This way you can easily send an exact plugin setting to someone — in an email or even a tweet — without any guesswork or screenshots.”

System Requirements

Mac OS X ≥ 10.9

Audio Unit 64-Bit, VST 64-Bit, VST3 64-Bit, or AAX 64-Bit host

Windows ≥ 7

VST 64-Bit, VST3 64-Bit, or AAX 64-Bit host” Contact Support “To send plugin feedback, please e-mail us at

If you have a quick question, send us a tweet @Goodhertz. We’re often able to respond faster to tweets than emails.

If you’re having trouble, experiencing a technical issue, or you think you’ve found a bug, please email

Find all our contact info & bug-reporting protocol on the contact page.