Click anywhere on the interface to jump to a control’s definition.

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.

Background

Left/Right Stereo

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

Purely Left & Right SignalsPurely 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 SignalsMid & 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:

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

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

UncorrelatedUncorrelatedWhen 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:

L/R in a GoniometerL/R in a GoniometerPurely left & right signals are seen in a goniometer

M/S in a GoniometerM/S in a GoniometerPurely & 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 -96dB
  • Max 12dB
  • Default 0dB

Mid Tilt Gain

Varies the amount of spectral tilt for the mid.

TiltTilt

  • Negative values tilt the sonic spectrum toward the bass .
  • Positive values tilt toward the treble .
  • Min -12dB
  • Max 12dB
  • Default 0dB

Mid Solo

Solos the mid signal.

  • Min Off
  • Max On

Mid Mute

Mutes the mid signal.

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

  • Min Off
  • Max On

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 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 -96dB
  • Max 12dB
  • Default 0dB

Side Tilt Gain

Varies the amount of spectral tilt for the sides.

  • Negative values tilt the sonic spectrum toward the bass .
  • Positive values tilt toward the treble .
  • Min -12dB
  • Max 12dB
  • Default 0dB

Side Solo

Solos the side signal.

  • 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.
  • Min Off
  • Max On

Side Mute

Mutes the side signal.

  • Min Off
  • Max On

Stereo Width Controls

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, toward , 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, toward , 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.

Width

ModeAbout
WidthThe conventional stereo width control. At 0% Stereo Width the output is completely mono; at 200% the stereo width is increased by +6dB.
NaturalA 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.
Shuffler A, B, CStereo 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): A = 320 Hz B = 640 Hz C = 1250 Hz.
M/S BlendBlends between mid & side. At 0% the output is completely mono (all mid), and at 200% the output is completely out-of-phase (all sides).

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 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 24000Hz
  • 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%

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.

  • Min Off
  • Max 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.

Output Mode

Sets the output signal format.

Flip L/R

Swaps the left and right channels.

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 12000Hz
  • Default 250Hz

Mid Tilt Range High

Sets the high frequency point for the tilt range.

  • Min 20Hz
  • Max 24000Hz
  • Default 20000Hz

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.

ModeAbout
AutoMidside automatically varies the gain to maintain the same perceived loudness.
NormFunctions like a typical tilt EQ: cutting and boosting an equal but opposite amount.
TrebleKeeps the gain of the bass fixed while varying the treble.
BassKeeps the gain of the treble fixed while varying the bass.

Side Tilt Range Low

  • Min 10Hz
  • Max 12000Hz
  • Default 250Hz

Side Tilt Range High

  • Min 20Hz
  • Max 24000Hz
  • Default 20000Hz

Side Tilt Loudness Mode

Specs

Supported Channel Configurations

Input Channel # Output Channel #
2 2

Acknowledgements

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

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

ActionKeyboard Shortcut
Enter New Parameter ValueOnce you’re 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 ParameterTab
Jump to Previous ParameterShift + Tab or ` (backtick)
Escape Parameter Focus / Close any Open DrawersEsc
Toggle A/BA (N.B. For this to work, you must have a control selected.)
Shift A to B / Shift B to AShift + 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

ActionInstruction
Reset Control to DefaultRight-Click & select “Reset [control] to Default”
Read about Control in ManualRight-Click & select “Read about [control]”
Lock a control when Switching PresetsRight-Click & select “Lock [control] When Switching Presets”
Copy all current plugin settingsRight-Click & select “Copy all settings as URL to Clipboard”
Paste all plugin settingsRight-Click & select “Paste all settings from Clipboard”
Reset all plugin settings to defaultRight-Click & select “Reset all settings to default”
Go to the plugin’s product pageRight-Click & select “Goodhertz [plugin name]”

Right-Click Preferences

ActionExplanation
Always Open Advanced PaneBy default, this is false — 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.
Enable MeteringBy default, this is true — 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 InputBy 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.
Window SizeEnlarge or shrink the Goodhertz plugin window by selecting an option here. This will save your preference for all instances of this plugin.

Mouse Modifiers

ActionCombination (Mac)Combination (Windows)
Reset Parameter to Default ValueOption + ClickAlt + Click
Move Control with Coarse PrecisionShift + DragShift + Drag
Move Control with Fine PrecisionCommand + DragCtrl + Drag
Move Control with Normal PrecisionDragDrag

Automation

Unintentional digital clicks and pops are the worst. They happen for lots of reasons and often end up wasting 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.co/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.co/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 ≥ 10.9

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 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.