Midside

Expressive stereo imaging

There are many mid/side plugins on the market, but few of them get to the point as quickly — or as well — as Midside does. Midside distills years of research on spatial audio and psychoacoustics, and hundreds of hours in the mastering room, into a powerful plugin that can be used on any stereo source. In only a handful of controls, Midside accomplishes more than other M/S plugins do in 50+.

As always with our plugins, Midside was built to be automated and moved around (even the mute and solo buttons won’t click or pop). Use it to manipulate space and depth; automate it to create more motion in your mixes or masters. If you’ve wanted more expressive control of your stereo image — this is the plugin.

Interface Preview

Here’s a screenshot of Midside in action. Click anywhere on the interface to jump to a control’s definition below.

Advanced Controls

Background

Left/Right Stereo

Most of the time, stereo audio is thought of as two channels: left & right.

Purely Left & Right Signals

The “stereo field” or “stereo image” describes the full soundstage that is produced by the left and right channels together. These two channels can be very similar, very different, or somewhere in between. Is the stereo field balanced or unbalanced? Directional or hazy? Left-heavy? Wide or narrow? All of these qualities of the stereo image are determined by the relationship between left & right.

When left & right are the same, the stereo image is mono and narrow sounding. When left & right are less similar, the stereo image becomes wider and more diffuse. When left & right are completely opposed (out-of-phase), the stereo image sounds very wide, directionless, and unnatural.

Mid/Side Stereo

Instead of left & right, stereo audio can also be thought of, and processed, as mid & side.

Mid & Side Signals

Everything that’s similar about left & right ends up in the mid, and everything that’s different ends up in the sides. Mid & side are often called “sum” & “difference” because, math-wise, mid is the sum of the left & right, and side is the difference.

M = L + R S = L - R

To put it graphically:

When left & right are the same, the signal is all mid, no sides.

When left & right are anticorrelated, the signal is all sides, no mid.

When left & right are uncorrelated, the signal is an equal mix of mid and sides.

Oftentimes, stereo audio signals end up being a mix of both mid and side components, just like most stereo signals (aside from hard panned ones) are a blend of left and right. It’s rare that a signal would (purposefully) only be “in the sides.”

Got it. But why does M/S matter?

Mid/side matters because of what you can do with it. With a basic understanding of M/S, and a killer M/S processor like Midside, the stereo field becomes something that you can control and manipulate directly, not just the byproduct of panning, levels, stereo miking, and effects.

  • Want to enhance the width and size of the chorus in your mix? Try automating up the Side Gain when the chorus hits.
  • Want a bridge section to feel smaller and more compact? Automate the Side Gain down.
  • Need to bring out the lead vocal in a crowded master? Try boosting the presence in the mid with the Mid Tilt Gain.
  • Want a drum kit to sound wide but with a tight low end? Increase the Stereo Width a little, and use the Mono Below section to keep the low end centered.
  • Want a string ensemble to envelop the listener with a warm stereo field? Try one of the Shuffler modes in Stereo Width Mode.
  • Want to compress the kick drum in a master without ducking the stereo elements? Create a M/S compressor by using Midside’s Routing features.

Visualization

Goniometer

Midside includes a real-time stereo display called a goniometer (or vectorscope). By interpreting the goniometer, it’s possible to quickly deduce many characteristics about the stereo field and the precise relationship between left & right channels.

Here are some examples of how simple stereo signals appear in the goniometer:

Purely left & right signals are seen in a goniometer

Purely & side signals as seen in a goniometer.

Tilt Frequency Response

Displays the frequency response of the tilt equalizer for both mid & side. Located in the advanced controls.

Controls

Primary Controls

Mid

Mid Gain

Adjusts the gain of the mid signal.

Mid Gain includes a level meter embedded in the slider. This meter shows the peak level of the mid signal both pre (lighter color) and post (darker color) Midside’s processing.

If the signal peak exceeds or equals 0.0dB the meter color turns red, indicating that clipping could occur. Midside 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

Mid Tilt Gain

Varies the amount of spectral tilt for the mid.

Negative values tilt the sonic spectrum toward bass frequencies

Positive values tilt toward treble frequencies

Tilt

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

Mid Solo

Solos the mid signal.

Options: Off, On

  • Default Off

Mid Mute

Mutes the mid signal.

Options: Off, On

Muting the mid allows you to monitor the sides “in-place” — as they are naturally in your mix.

  • Default Off

Side

Side Gain

Adjusts the gain of the side signal.

Side Gain includes a level meter embedded in the slider. This meter shows the peak level of the side signal both pre (lighter color) and post (darker color) Midside’s processing.

If the signal peak exceeds or equals 0.0dB the meter color turns red, indicating that clipping could occur. Midside 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

Side Tilt Gain

Varies the amount of spectral tilt for the sides.

Negative values tilt the sonic spectrum toward bass frequencies

Positive values tilt toward treble frequencies

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

Side Solo

Solos the side signal.

Options: Off, On

Side Solo is an “out-of-place” solo and places the side signal in the center (mono image) of the stereo field for easier evaluation.

If you’d like to monitor the sides as they normally exist in your mix, just mute the mid, using Mid Mute, instead of soloing the sides.

  • Default Off

Side Mute

Mutes the side signal.

Options: Off, On

  • Default Off

Stereo Width

Midside’s Stereo Width controls operate after the Mid & Side sections, providing different ways to change the width and character of the stereo field.

Stereo Width

Controls the width of the stereo field.

Moving the Stereo Width slider to the right widens the stereo field, emphasizing elements that are in the sides or outer parts of the mix.

Moving the Stereo Width slider to the left narrows the stereo field, emphasizing elements that are in the center of the mix.

At exactly 100%, the stereo field is unchanged (regardless of the Stereo Width Mode setting).

  • Min 0%
  • Max 200%
  • Default 100%

Stereo Width Mode

Stereo Width Mode offers several different modes for altering the width of the stereo field — each with its own unique sound & speciality.

Option Discussion
Standard

Conventional stereo width; 0% is mono; 200% is increased by +6dB
Natural

Psychoacoustically-tuned, natural-sounding
Shuffler A

Stereo shuffling mostly heard below 320 Hz
Shuffler B

Stereo shuffling mostly heard below 640 Hz
Shuffler C

Stereo shuffling mostly heard below 1250 Hz
M/S Blend

Blends between mid and side signals; 0% is mono (all mid); 200% completely out-of-phase (all sides)

“Natural”?

A natural sounding width control that uses everything we’ve learned about spatial audio and psychoacoustics. For Stereo Width values between 0%-100% the low end is more dramatically narrowed, similar to two speakers being moved closer together, and at 0% the output is completely mono. For values above >100% the stereo field becomes wider and more immersive, but the low end remains grounded.

Stereo Shuffling

Stereo shuffling is a classic processing technique that primarily widens the bass frequencies. Because humans are especially sensitive to stereo phase information in the low end, shuffling can produce very expansive, spacious stereo fields, while leaving the highs largely untouched. We chose our favorite shuffling frequencies (the frequency below which the shuffling effect is most dramatic).

  • Default Standard

Mono Below

The Mono Below section causes stereo signals to become more mono, below a certain frequency. Because making something mono simply means removing sides material, the Mono Below section operates primarily on the sides.

Mono Below Listen

Mono Below Listen makes it possible to directly monitor (listen to) the sides material that is being removed by the Mono Below filter.

  • Default Off

Mono Below Strength

Controls the overall strength of the Mono Below filters.

As the Mono Below Strength is increased, the Mono Below filter transitions from completely off at 0%, to a gentle shelf around 50%, to a more dramatic low cut filter at 100%.

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

Mono Below Freq

Selects the frequency where the Mono Below filter begins to act.

  • Min 4Hz
  • Max 24.0kHz
  • Default 4Hz

Mono Below Bass Makeup

Determines how much the bass in the mid is boosted to make up for any bass removed from the sides.

  • Min 0%
  • Max 200%
  • Default 0%

Master On/Off

Bypasses Midside’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 Midside’s advanced controls, click the ••• icon in the sidebar.

Routing

Input Mode

Sets the input signal format.

Options: Left | Right, Mid | Side

  • Default Left | Right

Output Mode

Sets the output signal format.

Options: Left | Right, Mid | Side

  • Default Left | Right

Flip L/R

Swaps the left and right channels.

Options: Left | Right, Right | Left

  • Default Left | Right

Advanced Panning

Mid Pan

Pans the mid signal of the stereo field.

  • Min -100%
  • Max 100%
  • Default 0%

Side Pan

Pans the side signal of the stereo field.

Panning the sides is generally much much less obvious than panning the mid.

Panning both Mid Pan & Side Pan together will behave like a normal stereo balancer.

  • Min -100%
  • Max 100%
  • Default 0%

Advanced Tilt

Mid Tilt Range Low

Mid Tilt Range Low & Mid Tilt Range High control the range in which the mid tilt EQ operates.

  • Min 10Hz
  • Max 12.0kHz
  • Default 250Hz

Mid Tilt Range High

Sets the high frequency point for the tilt range.

  • Min 20Hz
  • Max 24.0kHz
  • Default 20.0kHz

Mid Tilt Loudness Mode

Unlike a typical tilt EQ, which always boosts & cuts an equal amount in either direction, Midside is smarter. With Mid Tilt Loudness Mode set to Auto, the loudness is automatically matched for any tilt setting using our perceptual loudness locking technology. This makes comparing EQ settings much easier and makes it possible to perform more natural sounding tilt automations.

Option Discussion
Auto

Automatically varies the gain to maintain the same perceived loudness
Standard

Functions like a typical tilt EQ: cutting and boosting an equal but opposite amount
Treble

Keeps the gain of the bass fixed while varying the treble
Bass

Keeps the gain of the treble fixed while varying the bass
  • Default Treble

Side Tilt Range Low

See Mid Tilt Range Low.

  • Min 10Hz
  • Max 12.0kHz
  • Default 250Hz

Side Tilt Range High

See Mid Tilt Range High.

  • Min 20Hz
  • Max 24.0kHz
  • Default 20.0kHz

Side Tilt Loudness Mode

See Mid Tilt Loudness Mode.

Option Discussion
Auto

Automatically varies the gain to maintain the same perceived loudness
Standard

Functions like a typical tilt EQ: cutting and boosting an equal but opposite amount
Treble

Keeps the gain of the bass fixed while varying the treble
Bass

Keeps the gain of the treble fixed while varying the bass
  • Default Treble

Specs

Supported Channel Configurations

Input Channel # Output Channel #
2 2

Acknowledgements

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

Authors

Devin Kerr / Rob Stenson / Jasper Duba / Noah Dayan

Translators

TaeHo Park / Tiago Frúgoli / Gustavo Guzmán / Reda Kermach / Noah Dayan / Gal Cohen / Sydney Bolton / Enrico Cirene

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 reset at any time using the “Reset Meters” button (in certain plugins) and manually enabled or disabled via the “Enable Metering” User Preference.

Preset Bar

Button Action
Undo the last parameter change.
Redo the last parameter change.
Switch to the previous preset.
“Preset Name” Opens the preset drawer (Option/Alt + Click to reset all plugin settings to preset).
Switch to the next preset.
Selects the A settings state.
This copies the current settings to the opposite A/B state; i.e. if you’re on the A state, clicking the arrow will copy those settings to the B state.
Selects the B settings state.

Toolbar

Introduced in version 3.10, the toolbar at the bottom of the plugin holds a handful of shortcut buttons.

Icon Action
Opens preferences menu
Shows diagnostic information
Opens plugin manual in your default web browser
Opens a URL representation of the current plugin control state (Command/Ctrl + Click to copy the URL to the clipboard)
Opens language-selection menu
Opens MIDI Learn menu
Shrink interface
Enlarge interface

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
Tap Tempo t or Click (N.B. For this to work, you must have a BPM or milliseconds control selected.)
Save Preset n (N.B. For this to work, the preset panel must be open.)
Set Preset as Favorite f (N.B. For this to work, the preset panel must be open.)
Edit Preset e (N.B. For this to work, the preset panel must be open.)
Update Preset u (N.B. For this to work, the preset panel must be open.)
Delete Preset Delete (N.B. For this to work, the preset panel must be open.)

Right-Click Actions

Action Instruction
Read about Control in manual Right-Click & select “Show in Plugin Manual”
Reset Control to Default Right-Click & select “Reset to Factory Default Value”
Lock Control when switching presets Right-Click & select “Lock When Switching Presets”
Copy current plugin settings to clipboard Right-Click & select “Copy as URL to Clipboard”
Paste all plugin settings from clipboard Right-Click & select “Paste From Clipboard”
Reset all plugin settings to Defaults Right-Click & select “Reset All to Defaults”
Reset all plugin metering Right-Click & select “Reset Meters” (only available in certain plugins)
Reset all plugin settings to Preset Right-Click & select “Reset to [preset] Preset”
Update Preset with current plugin settings Right-Click & select “Update [preset] Preset”
Create new Preset with current plugin settings Right-Click & select “Create New Preset”
Go to the plugin’s manual page Right-Click & select “Read [plugin name] Manual”

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, Italian, 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.
Control Granularity By default, all Goodhertz controls move in small increments when dragged. If you prefer controls to operate with larger increments by default, change this option to Coarse. N.B. This will swap the behavior of the Shift mouse modifier - i.e. Shift-dragging will move a control with standard granularity when set to Coarse.
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 Hover Markers By default, this is On — i.e. all controls will show markers on hover. If you find this behavior unnecessary, deselect this option and no markers will be shown.
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.
Enable Tooltips By default, this is On — i.e. all controls will show a tooltip on hover. If you find this behavior unnecessary, deselect this option and no tooltips will be shown.
GPU Acceleration By default, this is Enabled — i.e. the GPU will be prioritized whenever possible to improve graphics performance. If your graphics card does not support GPU acceleration, this preference will be automatically set to Reduced. N.B. If you experience graphics issues, disabling this preference may help.
Keyboard Focus By default, you can get keyboard focus on any Goodhertz control with a single click. Change 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.
Diagnostics Displays general information about the plugin and the configuration of your system for diagnostic purposes. If you experience any issues with the plugin, it can be helpful to include this information when contacting us. N.B. Clicking this window will copy the contents to the clipboard.
MIDI Learn Configure the mapping used to control parameters via MIDI messages. To assign a MIDI number to a control, enable MIDI Learn and send a MIDI message while a control is focused. To remove an assigned mapping, click on a mapping entry in the list or select Clear All to reset the entire mapping. N.B. You can assign different types of MIDI messages including Pitch Bend, Note, and CC messages.

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

Automation

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: https://goodhertz.com/vulf-comp/3.0.9?cm=0&wf=0&lf=100&lfc=50

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 “https://goodhertz.com/vulf-comp/3.0.9?cm=0&wf=0&lf=100&lfc=50” 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 ≥ 10.13

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

Windows ≥ 10

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

Contact Support

To send plugin feedback, please e-mail us at feedback@goodhertz.com.

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 support@goodhertz.com.

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