REVERSIDE User Manual 0.9.4

Product version: 0.9.4 [Build 345, June 30, 2025]
Manual edition: 102

Current Version Important Notes

1. Although this version is feature-complete, it is not yet the final product.
2. A small library of factory presets is meant only for testing purposes. They have not been made for production use, nor have they been made by experienced reverb preset designers. In no way can they demonstrate the full spectrum of the Plug-In's capabilities.
3. The CPU usage may vary drastically depending on parameter values.
4. The reverb DSP code has not yet been vectorized or optimized. The release version is expected to be 3-5 times faster.
5. User Interface: The user interface is still under development and is subject to changes.

1. Introduction

REVERSIDE is a sophisticated dual-engine reverb processor that combines Early Reflections (ER) and Late Reflections (LR) to create realistic acoustic spaces and creative effects. Both ER and LR engines feature an additional Diffuser which can be treated as an extra mini reverb. Diffusers are part of ER/LR engines and cannot be used independently.

The unique features of REVERSIDE are:

• Comprehensive stereo imaging capabilities
• Deep control of Early Reflections
• Spectral Panning

This manual explains all features and parameters in detail.

REVERSIDE came into existence due to invaluable support from Jeffrey Jaskunas of Altitude Audio. Altitude Audio offers a set of products to measure one's personal hearing profile and a Plug-In (as well as standalone application) to compensate for the measured profile deficiencies. If you like REVERSIDE, please consider visiting the Altitude Audio website at:
https://altitude.audio

Altitude Audio Full Music Spectrum Hearing Test is a free mobile app for iOS and Android. It takes about 8-15 minutes to measure your full personal dual-ear hearing profile. It's an indispensable tool if you are into audio/music production. It will help you identify those frequency spectrum areas where you need special attention while mixing.

2. Getting Started

2.1. Installation

2.1.1 macOS

Unpack the downloaded zip file, navigate to the /MAC sub-folder and double-click on reverside.pkg. A standard macOS installer will open. You can choose which Plug-In formats (VST3/AUv2/CLAP) to install. Note that you will have to provide the admin password during installation.

• VST3 Plug-In will be installed into the system's VST3 directory:
  /Library/Audio/Plug-ins/VST3
  as DPA_Reverside.vst3
• AudioUnit (v2) Plug-In will be installed into the system's AUv2 directory:
  /Library/Audio/Plug-ins/Components
  as DPA_Reverside.component
• CLAP Plug-In will be installed into the system's CLAP directory:
  /Library/Audio/Plug-ins/CLAP
  as DPA_Reverside.clap
• Main files (such as skin, preferences and presets) are installed into:
  /Users/Shared/Devproaudio/REVERSIDE
• Presets are stored under /presets of the above folder.

2.1.2 Windows

Unpack the downloaded zip file, navigate to the /WIN sub-folder and run install.exe. The installation will require admin rights. You can choose which Plug-In formats (VST3/AUv2/CLAP) to install.

• VST3 Plug-in is installed as DPA_Reverside.vst3 into:
  C:\Program Files\Common Files\VST3
• CLAP Plug-in is installed as DPA_Reverside.clap into:
  C:\Program Files\Common Files\CLAP
• Main files (such as skin, preferences and presets) are installed into:
  C:\ProgramData\Devproaudio\product\REVERSIDE
• Presets are stored under /presets of the above folder.

2.2. Uninstallation

2.2.1 macOS

a) Remove specific Plug-In files:

• /Library/Audio/Plug-ins/VST3/DPA_Reverside.vst3
• /Library/Audio/Plug-ins/Components/DPA_Reverside.component
• /Library/Audio/Plug-ins/CLAP/DPA_Reverside.clap

b) Remove main folder:
/Users/Shared/Devproaudio/product/REVERSIDE

2.2.2 Windows

Navigate to:
C:\Program Files\devproaudio\product\REVERSIDE
and run uninst00.exe

Note that user-saved preset files and folders will not be deleted from:
C:\Program Files\devproaudio\product\REVERSIDE\preset
You would have to delete them manually.

2.3. Authorization

Launch your DAW/host. You can find the Plug-In in your host as:
REVERSIDE (DevProAudio)

The Plug-In will run in DEMO mode (indicated by [DEMO] text in top bar) until you authorize it. In DEMO mode you can evaluate the Plug-In as long as you want. There is no noise added, no drop-outs, no other distractions. The only limitation is that you CANNOT save presets and Plug-In state in DAW's project is NOT retained.

Authorization procedure:

1. Instantiate the Plug-In in your host software and open the Plug-In window. Upon first load, the Plug-In will display the [ABOUT] page where you can provide your serial code.
2. Open your email client. Text-select the provided serial code and copy it to clipboard by hitting Cmd-C (Ctrl-C on Windows). Go back to the Plug-In. Click [PASTE FROM CLIPBOARD] button. The serial will show up in the serial box. Click [VERIFY SERIAL] button.
3. If everything is OK, the status text will change to <Verified> and the [DEMO] text in top bar will disappear.
4. If the serial code does not show up, you can enter it manually by clicking on the serial field and then entering it letter by letter. You can use backspace to correct any errors. When finished with entering, hit ENTER key. Once fully entered, click [VERIFY SERIAL] button.

Authorization procedure DOES NOT require an internet connection.

NOTE: REVERSIDE authorization DOES USE some anonymous system settings on authorization as part of its copy protection system. These settings have no personal data which can uniquely identify your system. The settings are stored in encrypted form in the Plug-In's main folder and are not sent out to any server.

2.4. Privacy

DEVPROAUDIO respects your privacy. REVERSIDE Plug-In does not collect any personal data. The Plug-In binary code does not have any network connection code at all and simply cannot send/receive any data to/from any server. You can verify this by using specific network activity monitoring software.

2.5. VST3 Legal Notice

At the moment, Steinberg has not countersigned the VST3 Plug-In agreement with me. I've been trying to contact them over the past half year, but they don't reply. I would appreciate any help in getting this resolved. If you are using Steinberg products, you could help by contacting them. This also means that REVERSIDE has not been tested by me in Steinberg's products such as Cubase/Nuendo/etc. At the moment I have to rely on beta tester feedback.

2.6. Ableton Live 12 Compatibility

I have no access to Ableton Live version 12. This means I cannot test compatibility of REVERSIDE with Ableton Live 12. I still have access to previous versions of Ableton Live though.

3. Reverb Engine Architecture

Key Terms

• ER: Early Reflections - Initial sound reflections that provide spatial cues
• LR: Late Reflections - Dense, diffuse reverberations that create ambience
• UI: User Interface

REVERSIDE uses a sophisticated dual-engine design:

• EARLY REFLECTIONS (ER) ENGINE
  • Simulates initial sound reflections
  • Provides crucial spatial cues
• LATE REFLECTIONS (LR) ENGINE
  • Simulates late, dense reverberations
  • Responsible for the sense of space and ambience

Both engines also offer their own additional diffuser engines which can be treated as an additional layer of reverberation, making it actually a 4-engine reverb.

Signal Flow

• ER: [IN] → [REFL] → [MAT FLT] → [DIFF] → [EQ] → [STEREO] → [PRE-DLY] → [ER OUT]
• LR: [IN + ER SEND] → [REFL] → [REV] → [DCY FLT] → [DIFF] → [EQ] → [STEREO] → [PRE-DLY] → [LR OUT]
• OUT: ([ER OUT] + [LR OUT]) + INPUT

4. User Interface Controls

3.1 Control Help Tooltips

If you hover the mouse over a control, a help tooltip with brief control designation will show up in the status bar area. Make sure that the current status bar page is set to [HELP] page (click on the leftmost button in status bar and select [HELP] in pop-up menu if it's not the case).

3.2 Knobs & Sliders

• Mouse-drag: Changes the value
• Holding SHIFT while dragging: Changes the value slower. Use it to fine-tune the value
• CTRL-mouse-click: Resets the control's value to its default value
• ALT-mouse-click: Toggles on/off parameter lock mode for this control

3.3 Working with Edit Boxes

• Double-mouse-click: Opens an edit box where you can enter a value
• When you start typing, the value will be auto-deleted
• Pressing ESC key will close edit box and discard changes
• ENTER key will keep changes
• DEL key removes all entered value
• BACKSPACE removes last symbol
• Clicking outside the edit box will discard changes (except for Preset Browser's)

NOTES:

• Full edit box functionality with cursor/selection/navigation is not yet implemented
• Keyboard input does not work in AudioUnit yet
• Some characters are not allowed: SPACE

3.4 Parameter Pages

All REVERSIDE parameters are grouped into 7 pages:

• [TIME] Some ER parameters + LR parameters
• [SPACE] All ER parameters
• [DIFFUSE] ER/LR Diffusers
• [FILTER] MAT/DCY filters
• [EQ] ER/LR EQs
• [STEREO] Stereo imaging controls
• [MIX] Mixing controls + modulation controls

You can switch between pages by clicking on the respective page button available in the left side bar.

3.5 Plug-In Window

You can change the Plug-In window size by dragging the window's right-bottom corner. Some hosts might not support this though and currently AudioUnit cannot do that. Alternatively you can change the window size in UI preference menu. See section [6.2.3].

5. Preset Management

Access the preset panel by clicking on the preset info in top bar or by clicking on the [PRESET] tab in side bar.

Presets are organized into 4 lists (from left to right):

1. Preset sub-type
2. Preset Bank (Factory, User, Imported)
3. Preset Folder (Hall, Room, etc.)
4. Preset List (2-column view)

The topmost item called 'Full' in preset sub-type list corresponds to a full set of parameters. Other sub-types such as ER, MOD, MIX etc correspond to a specific sub-set of all preset parameters. For example MIX includes only mix related parameters. There are 22 sub-types. The first 20 is reverb sub-sets, while the last 2 sub-types correspond to system settings: P-Lock is a list of locked parameters and Color is a Color Scheme.

Buttons (from left to right):

• [CLOSE] Closes the panel. You can also close panel by clicking on [preset info] button in top bar just by selecting another tab/page.
• [PIN] when ON keeps the panel open while changing presets in preset list. Use it if you want to audition multiple presets.
• [ACTION MENU] The 3 buttons (with 3 horizontal lines) under Bank/Folder/Preset are used to access action menus. Currently only the 3 actions are implemented:
  • Create new
  • Rename
  • Remove
• [<][>] buttons will list through presets in selected folder
• [RESAVE]: Updates currently selected preset with new settings. This button is only available when a preset is selected.
• [SAVE...]: Creates a new preset in current bank/folder

Saving a New Preset:

Click on [SAVE...] button. You will see a new set of controls at the bottom of the panel:
[ACTION PROMPT] [NAME] [CANCEL] [CONFIRM]

Click on [NAME] and edit box will appear indicated by blinking cursor. Type in a new name and press [ENTER] to confirm and then press [CONFIRM]. To discard changes press [CANCEL].

When entering preset/file/folder name in Preset Browser the edit box is open on a single-mouse-click. Clicking outside the edit box will RETAIN the changes. This way you can click on [CANCEL] or [CONFIRM] buttons without having to press ENTER key if you want to, however it's recommended to use [ENTER] key to confirm changes to edit boxes.

If you enter a name that already exists, you will be asked to confirm overwrite.

NOTE: AudioUnit version does not support keyboard input yet so once you click on [SAVE...] a standard system Save File dialog will appear where you can enter a name.

If you want to update (resave) a currently selected preset, press [RESAVE...] button, then click [CONFIRM]. Note that in this mode you cannot change the name of the preset.

Creating/Renaming/Deleting Presets/Folders/Banks (from menu actions) is a procedure similar to the above.

6. User Interface Overview

The interface is organized into four main panels (top to bottom):

1. Top Panel: Main controls and navigation
2. Reverb Tab Side Panel (at left): Parameter page selection
3. Parameter/Controls Panel: Detailed controls for selected tab
4. Bottom Panel: System information, color edit etc

6.1 Top Panel

[DEVPROAUDIO]
Clicking on above logo or [REVERSIDE] tab opens the About page with product information and licensing. Here you can enter your product serial code and check the version information.

Preset Controls:

• <> buttons will load previous/next preset in currently selected folder
• Clicking on preset info button will open Preset Browser page (which is the same as clicking on [PRESET] tab in side panel)

Preset info format is: bank | folder | preset

[BYPASS] Button: Enables/disables reverb processing

6.2 Bottom Bar

Click on rightmost button to open Bottom Bar Menu and select which page to display.

6.2.1 HELP

When selected the bottom bar will display a tooltip info when you hover over a control.

6.2.2 INFO

Will display version information.

6.2.3 UI (User Interface Preferences)

• [LANGUAGE] click on button to change UI language
• [THEME] click on button to change UI theme
• [UI SCALE] click on button to change UI scale. Use it for AudioUnit version as it does not support dynamic UI re-sizing

NOTE: REVERSIDE supports a full localization of the Plug-In's User Interface. It's as easy as just editing some text files in the skin folder and finding font files that support your language. This can be done with the help of AI tools that could do the bulk of translation job. Feel free to contact me for details.

6.2.4 FONT

• [FONT SET] click on button to select font set from menu
• [SIZE] drag the slider to adjust UI font size
• [SPACING] drag the slider to adjust UI font spacing

6.2.5 EDIT COLOR SCHEME

Here you can edit color schemes using HSL (Hue/Saturation/Lightness) color model.

• Select which UI element you want to edit via two menus: [UI ELEM TYPE] [SUB TYPE] (for example: [panel] [main panel back])
• Set Hue, Saturation and Lightness values. Hue is absolute, S/L are relative to values specified in the skin:
• [H] absolute HUE value [0..360]
• [S] edit relative SATURATION value [-80..80]
• [V] edit relative LIGHTNESS value [-50..50]
• You can save the current color scheme as a preset file. Click on [BROWSE] button to open Preset browser. The [Color] preset sub-type will be pre-selected. Now you can save and load color schemes. Current color scheme settings along with global color settings are saved as shared settings and thus are shared between all Plug-In instances.

6.2.6 EDIT GLOBAL COLORS

Here you can adjust colors globally. These adjustments are applied to all color themes (though without actually changing them) so if you have any non-zero values here, the loaded color scheme will look different especially if you adjust Hue more than 10%. These are meant primarily to adjust saturation and lightness to your personal preference without having to change the color scheme.

• H(Hue), S(Saturation), L(Lightness) values are relative to the color scheme base color.
• [SLIDE TIME] Dynamic color changes in REVERSIDE are applied gradually to make a nice smooth transition effect. Use this slider to adjust the time of the transition.

6.2.7 PERFORMANCE

This page shows the CPU usage of the Plug-In. It DOES NOT show the single core's or overall system CPU usage.

6.2.8 PARAMETER LOCKS

Parameter locks allow you to prevent specific controls from being changed when switching presets. Note that in locked state you can still change the parameter value.

• To lock a parameter: Click on a control while holding ALT key. This will toggle the lock
• A locked parameter will change its look (italic font and different color)
• The list displays a string of all locked parameters. Click on this list to show all locked parameters in a menu.
• Currently locked parameter set can be saved (and loaded back) as a sub-preset.
• [RESET] clicking on this button will reset all locks
• [BROWSE] will open Preset Browser with Param Lock sub-type pre-selected so you can quickly load/save locked param sets

6.2.9 Audio IO

Shows Host's sample rate.

6.2.10 Message

[reserved for future use]

6.2.11 Preset Browser

This is a mini preset browser. It's handy if you want to change presets while being able to see the changes in preset parameters. The buttons (from left to right) correspond to: [SUB-TYPE] [BANK] [FOLDER] [PRESET]

Click on these to change the selected Sub-Type/Bank/Folder/Preset or use [<][>] button to go to previous/next preset.

6.3 Side Bar (at left)

Here you can switch between parameter edit pages and quickly access important parameters.

• [ER][LR] ER/LR Engines ON/OFF
• [MAT][DCY] ER/LR Mat/Dcy Filters ON/OFF
• [DIF][DIF] ER/LR Diffusers ON/OFF
• [EQ][EQ] ER/LR Output Equalizers ON/OFF
• [MOD][MOD] ER/LR Modulation ON/OFF

7. TIME / MAIN

The page hosts:

• Time view display (top row)
• ER Position display (top row)
• LR Controls (bottom row)

Filter Mini Displays

• Hover over control to see transparent slider
• Drag to control 3 bands
• Press [EDIT] to go to full editor

Time Display

Displays the reverb envelopes as two curves which correspond to (L/R or M/S) and Early reflection taps, both with corresponding amount of pre-delay applied.
X axis: ms/s
Y axis: in dB (so exponentially decaying envelope looks as a straight line)

NOTE: Here reflection taps are displayed in dB whereas on [SPACE] tab they are displayed in % (i.e. absolute gain value) so they might look different.

Quick slider controls beneath the time display. From left to right:

• Reference space size
• Shape
• Walls related absorption
• (Distance induced) decay rate
• Stereo width
• Number of reflections to use

Mini Position Display

It's the same as Position Display on [SPACE] tab. Quick slider controls beneath the display. From left to right:

• Distance
• Geom pan
• Mic separation
• Displacement X
• Displacement Y
• Rotation in XY plane

Pre-Delay Controls

Click on a button next to [PRE-DLY] to access different pre-delay modes. ER and LR have different pre-delay modes as follows:

• ER PRE-DLY: [AUTO], [ABS FREE], [ABS SYNC], [REL]
• LR Pre-Delay: [AUTO LR], [AUTO ER], [ER], [ABS FREE], [ABS SYNC], [ER+]

In [ABS FREE], [REL] and [ER+] modes you will see an additional slider next to sync mode button. This control lets you specify actual value.

In [ABS SYNC] modes you will see an extra button next to sync mode button. Click on it to access the time division menu.

In [AUTO] modes the pre-delay value depends on ER Engine Geometry settings.

Whatever the mode, the actual result pre-delay value is always displayed next to [PRE-DLY].

Hint: Use [AUTO] modes to get the most natural results. Use [ABS SYNC] modes if you want to create host tempo-synced effects.

Reverb/LR Section

REV TIME

The RT60 parameter refers to the time it takes for the reverb signal to decay to -60 dB from its initial level. This measurement is crucial for understanding the duration and character of the reverb effect in a mix.

• Short RT60 Values: When set to shorter RT60 times, the reverb decays quickly, which can create a tighter and more controlled sound. This is ideal for fast-paced music styles or situations where clarity and definition are essential, as it prevents the reverb from muddying the mix.
• Long RT60 Values: Conversely, longer RT60 times result in a more prolonged reverb decay, creating a lush and expansive sound. This setting is often used in genres that benefit from a sense of space and atmosphere, such as ambient or orchestral music.

The RT60 parameter is a fundamental aspect of reverb processing, allowing you to control the decay time of the reverb effect.

DENSITY/CONFIGS

In a reverb, the density of reflections increases rapidly over time, however there are a lot of cases when you want to have more initial density like in case of sounds with lots of fast transients like drums.

Click on a button beneath [DN PAN] to access 4 density configs:

• [CONF 1] base density. In this mode the density knob is disabled. Works good on sustained sounds with low level of fast transients.
• Then the higher the number the more density.

The knobs control the level of density WITHIN currently selected config.

Hints: CONF 2,3 are good for vocals, CONF 3,4 are good for drums.

DIFFUSE

Controls the diffusion of reverb tail. Use low values if you want to get sparser reverb tails. Basically DIFFUSE is a way to get the reverb tail density down.

WIDTH

Controls stereo width of reverb. NOTE that ER's stereo width is controlled independently.

[STD/WIDE] button switches between normal and wide stereo modes. NOTE: WIDE mode is meant for FX. In WIDE mode the result reverb might have some stereo artifacts/imbalances. Use STD mode to get natural sounding results.

SPREAD/CURVE

Control a spread of delays inside reverb, for natural sounding use [25-40%] value ranges. Bigger value will favor longer delays (and vice versa). Use bigger values if you want to increase a perceivable acoustic space size. Extreme values might sound unnatural. Use them for FX only.

This parameter basically allows to control the perceivable acoustic space size of the reverb tail independently from the main SIZE parameter on [SPACE] page.

CURVE works in conjunction with [SPREAD] to control the shape of the reverb tail. Extreme values will make the effect of [SPREAD] more pronounced. Control the span of reverb build-up. Higher REV SPREAD values will increase the perceived depth/size of a space.

CONTOUR

Controls the shape of initial reverb envelope. Higher values will produce a slower build-up.

PD MIX/SCALE

Envelopment control. These controls are effective means to increase the enveloping effect of reverb. Its effect is perceived as adding more depth to the space.

BASE CONFIG

Beneath [CURVE] label you can find a button to access base reverb configurations.

Controls the order or how many base delay lines are used in reverb. Higher values will result in a more dense and complex reverb (and use more CPU). For most of the cases STD config is enough.

This controls the overall density config. Note that even with SUPER density config it's not possible to increase much the initial reverb density. For this purpose use the [DENSITY/CONFIGS] controls.

Envelope Controls

Click on a button below [CV PAN] to access 2 envelope modes:

• [STD] produces natural exponential decay reverb found in most reverbs. In this mode the envelope controls [CV/DCY] are not available.
• [FAT] special extended mode where you can control the attack and decay of the reverb. Use FAT mode to add more body/energy to reverb, works well in simulating Halls and on synths. Note that Time/Envelope display's Y axis is in dB thus an exponentially decaying curve is shown as line.

[CV/DCY] parameters allow you to shape the envelope, slowing attack and blending between faster-than-exponential and slower-than-exponential decay profiles.

The result decay profile curves are displayed in TIME display.

Note: FAT mode comes at higher CPU usage.

Understanding Panning Controls

Some of reverb parameters have corresponding PAN controls. These controls allow to split the base parameter value into two values acting on L and R (or Mid/Side depending on STEREO control settings) channels.

Positive Pan values will scale down base value for R channel, and negative values the L's respectively.

For example let's take RevTime / RT Pan pair.

If RevTime = 2s, and RT_Pan = -100, the Left channel's rev time will be around 0.2s, and Right's remain 2s. The actual amount/depth of scaling down depends on particular control.

The list of parameters that have Pan controls are:

1. [RT PAN] Reverb Time
2. [DN PAN] Density Pan
3. [CV PAN] Envelope CV Pan
4. [DCY PAN] Envelope DCY Pan

The result panning curves (except DN PAN) are displayed in TIME display.

[CV/DCY PAN] allows to create different decay profiles for left/mid and right/side channels. For example you can set reverb MID channel to decay slower than reverb SIDE channel.

Pan controls are also available in [FILTERS].

The lower values of Pans can be used to add more spectral stereo variations to reverb. Higher values are meant for creative FX. The most interesting use cases are when panning is used with stereo controls. For example in Mid/Side mode.

8. SPACE

Design your acoustic space and place sound source and listener.

Reflections Display

Displays time/gain distribution of reflections.
X axis: ms/s
Y axis: in % to absolute gain

Size Controls

These allow to specify acoustic space sizes. Note that this affects both ER and LR.

• [Abs/Rel] button under REFL DISPLAY switch between absolute and relative mode. In absolute mode you set the X/Y/Z dimensions of a space in meters. In relative mode you set the relative dimensions of a space in respect to reference size.
• [SIZE] Reference Size in meters. Available in relative mode only.
• [Width (X)] Space width. Absolute mode: meters, Relative mode: relative (in %) to reference size.
• [Depth (Y)] Space depth. Absolute mode: meters, Relative mode: relative (in %) to reference size.
• [Height (Z)] Space height. Absolute mode: meters, Relative mode: relative (in %) to reference size.

SHAPE

Controls the space irregularity (0-100%)

0% = HARD RECTANGULAR ROOM, note that this might sound highly resonant unless you use asymmetrical positions. Note that positioning controls work better if shape is below 30% and higher values will introduce more randomness and smear the effect some.

100% = RANDOMIZED SPACE within the specified size controls

WALL ABSORPTION

Controls walls absorption, i.e. how much energy is absorbed by the walls. The bigger value will make reflections decay faster. Negative values revert the effect making it raising in gain. You can use this to create reverse room effects.

DECAY

This is distance-induced decay rate. This controls how fast reflections decay with distance. Higher values will result in faster decay, creating a more dense and complex reverb. Negative values revert the effect making it raising in gain. You can use this to create reverse room effects.

TIME WARP

The effect of this parameter is to compress or expand the time axis favoring shorter or longer delays. 0 = no compression/expansion = natural reverb. Use it to create unusual reflection patterns.

FILL IN

Simulates space contents. I.e. how stuffed a space is.
0 = empty space
100% = fully stuffed space

It works in conjunction with [MAT] filters which make the effect more pronounced.

REFL NUM

Number of reflections to use. From 5 to 200. Higher values → more CPU usage. For most of the cases values in [20-50] range are enough.

Hint: Adding ER Diffuser will produce additional diffuse reflections so it's possible to use low values with Diffuser enabled.

WIDTH

Controls stereo width of ER section. Do not confuse it with Reverb Stereo width. They work separately.

Important Note: Width = 0 will produce MONO output ONLY if positions of sound source and listener are symmetric in respect to walls which renders a MONO reflection pattern.

CROSS

Controls cross-mix of L/R channels in ER section.

Surface Bounce Types

These control how sound wave bounces off reflective surfaces.

• [OFF] Soft bounce. The phase is retained
• [ON]: Hard bounce. The phase is inverted

4 ON/OFF buttons at the bottom. From left to right:

• Wall: Side surfaces
• Floor: Bottom surface
• Ceiling: Top surface
• Random: Random surface

Understanding Positioning

In REVERSIDE, you have 3 points that you can allocate within acoustic space:

• Listener's L and R points (or you may say mics)
• Sound source (one source)

Or as you can rotate the positions you can also treat this arrangement as two sources and one listener.

There is no difference in the effect of this because neither head's shape nor radiation pattern are taken into consideration. REVERSIDE is not designed to be a positioning tool.

IMPORTANT NOTE: The positioning only affects the result Reflection pattern, which in turn affects ERs the most. It's not applied to direct signal path. This means adding direct/dry and/or LR signals will shadow the effect.

POSITION DISPLAY

Displays positions of listener's L and R (two yellow circles) and position of sound source (green circle) in X/Y. Consider it as a bird's eye view of the an acoustic space from above.
X axis corresponds to horizontal distance (room's width)
Y axis corresponds to room's depth

Important note: X and Y axis are normalized to 1.0 regardless of room's size. Take this into account when you design a narrow space like a tunnel.

DISTANCE

Controls a distance between a line connecting listener's L and R points and sound source.

GEOM PAN

Displacement (from symmetric mid position) of sound source in relation to listener's L and R points. Any values other than 0 will result in asymmetrical disposition.

MIC SEP

Controls a distance (in X/Y plane) between L and R points.

DIS X

Displacement (from symmetric mid position) of both listener and sound source in X direction.

DIS Y

Displacement (from symmetric mid position) of both listener and sound source in Y direction.

With displacements you can put listener and sound source close to walls. Any values other than 0 will most probably result in asymmetrical disposition.

ROT XY

Rotation (in XY plane over center) of both listener and sound source. Any values other than 0 will most probably result in asymmetrical disposition.

SRC/DST Z POS

Z position of sound source and listener.

There are two modes: [REL] and [ABS]

• REL: Z position is relative to effective space height
• ABS: Z position is absolute position in meters

As most of acoustic setups place sound source and listener in [0.5..3] meters range regardless of acoustic space size, the most natural is to use ABS mode.

RESET

Click on this button to reset all geom position controls to their default values.

NOTES

A) Reflection patterns ALSO affect the sounding of Reverb (LR) section.

9. DIFFUSERS

Overview

Diffusers are important tools to shape reverb sound.

There are two separate diffusers: one for Early Reflections (ER) and one for Late Reflections (LR). Even though they have similar parameters, they actually work internally differently.

Early Reflections (ER) diffuser

The primary function of the ER diffuser is to add additional diffuse reflections to the Early Reflections (ER) section. More diffuse reflections will result in a more natural and spacious sound as they correspond to having more reflective surfaces in the space. They add that sense of presence.

Late Reflections (LR) diffuser

The primary function of the LR diffuser is to add some extra control over build-up of reverb. This is important as using [FAT] envelope has some limitations on how slow the attack could be. Diffuser allows to further slow down the initial attack of reverb while making it denser at the same time. This also might add a sense of depth to reverb.

NOTE: Using too much of diffuser might result in somewhat unwanted resonant sounding.

Parameters

• LENGTH: The length of a diffusion filter. The longer the filter, the more dense the sound and the slower the attack.
• DENSITY: The density of the diffusion. The higher the density, the denser the sound. The more pronounced the effect is. Note that high values might result in a resonant sound.
• SPREAD: The relative time-span of the filter.
• DECAY: Controls attack/decay profile. Negative decay values produce slower/longer build-up.
• MIX: The amount of diffuser's output mixed into section (ER or LR) output. Thus 0 value = no diffuser, 100 = full diffuser.
• PAN: Controls the panning of diffuser output. It will shift the stereo image to either left/mid or right/side channels.

10. FILTERS

Overview

REVERSIDE features two types of filters that control the frequency dependent absorptions of surfaces:

• MAT (Material) filter
• DCY (Decay) filter

Click on [MAT] or [DCY] button to toggle the respective filter ON/OFF.

The difference is that in MAT filters the absorption is controlled by gain (in %), whereas in DCY filters the absorption is controlled in respect to reverb time (in % of reverb time).

Although MAT are applied to ERs and DCY to LRs, you can make one of the filter apply to both ERs and LRs by using special [FLT MODE] switch:

• [ER|LR]: ER and LRs are controlled independently
• [ER->LR]: ER controls LR (edit ER, LR will match)
• [LR->ER]: LR controls ER (edit LR, ER will match)

Please note that MAT filters Y axis is in % to filter's actual gain whereas DCY filters is in % to reverb time and the conversion between two types depends on reverb time and delay allocation.

Use ER->LR mode if you want to apply some material to all the reverb and do not care about resulted reverb times at specific bands. It's like a scientific/simulation approach.

Use LR->ER mode for more traditional reverb editing mode where you control the decay profile in respect to reverb times.

Note that using [ER|LR] mode might result in some unnatural spaces as there is no more coherency between ER's and LR's frequency profiles. Or one may use this mode to simulate 2 different materials albeit indirectly.

Using Multi-Band Filter Editor

All filters in REVERSIDE are organized as 3-band controls where you can control the 2 frequency split points between bands, 3 band's gains and 2 transition steepness between splits.

Essentially this 3-band scheme is implemented as two shelving filters in series with corresponding frequency, gain and Q factor controls. In addition to that there are 3 band gain's pan controls.

With Band's Gain Pan controls one can specify different frequency profiles for left/mid and/or right/side channels allowing to create interesting spatial effects.

You can use the mouse wheel to control the filters. By default, it changes the band's height; if you move the mouse closer to the split line so it becomes highlighted, you can control the filter's Q value. Note that Q is per split, not per band. Another way to change Q is by holding the Alt key.

NOTE 1: The actual result filter is depicted as CURVE.

NOTE 2: If any of filter pans are not zero separate curves for L and R are displayed.

11. EQ

Output EQs for ERs and LRs.

Output EQ filters are controlled in the same way as MAT/DCY filters. In addition here you can change filter types as:

• FILTER TYPES Options include S12, S24, S48, C12, C24, C48. S = Shelving, C = Cut filters.

12. STEREO

Here you have 5 rows of controls. The upper two rows correspond to ER (top) and LR (below), the third row corresponds to ER, the 4th and 5th rows to LR.

• IN WIDTH [ER/LR]: This allows to control the stereo width of input that goes into ER and LR modules.
  • 0 = no changes to stereo width (default)
  • 100 = collapse to fully mono
  • -100 = isolate Side signal
• WIDTH [ER/LR]: Stereo width
• CROSS [ER/LR]: Cross-mixes L/R channels. ER/LR cross parameters are implemented in a different way
• PAN/BAL [ER/LR]: Channel panning/balance. -100 = full left/mid, 100 = full right/side
• BLEND/ROTATE [ER/LR]: Selects stereo manipulation mode:
  • [BLEND] in this mode the knob controls the blend between 0 = fully stereo and 100% = fully Mid/Side mode
  • [ROTATE] in this mode the now bipolar knob controls the rotation of stereo field:
    • -100% rotate by -45%
    • +100% rotate by +45%
• DLY PAN [ER/LR]: Delay Pan control. This adds extra delay to either Left (-100) or Right (100) channel
• DIFF PAN [ER/LR]: Diffuser's Panning control. Note that it works if DIFF MIX > 0
• B1/B2/B3: Correspond to Mat/Dcy band's pans, which you can also control on FILTER page with visual feedback
• GM PAN [ER]: Geometric Pan.
• ROTATE [ER]: Geometric Rotate.
• DENSITY [LR]: LR Density Pan
• REV TIME [LR]: Reverb Time Pan
• ENV CV [LR]: Envelope Curve (CV) Pan
• ENV DCY [LR]: Envelope Decay (DCY) Pan

13. MIX

INPUT

Input gain in dB

INPUT MUTE

When turned on the input signal will be muted.
NOTE: All [MUTE] button states are saved in the preset/project state.

DRY/WET/MIX/OUT

Dry/Wet mix balance controls. There are TWO ways to control the mix of dry and wet signals:

1. Either via DRY/WET pair (direct gains in dB)
2. Or via MIX/OUT pair (relative mix and output gain in dB)

If you change DRY/WET, MIX/OUT will be re-calculated automatically and vice versa.

[MIX] is a mix balance in percent (0 = fully DRY, 100 = fully WET)

DRY MUTE

When turned on the DRY signal will be muted

WET MUTE

When turned on the WET signal will be muted

MIX LOCK

When turned on the WET/DRY section controls (along with MUTES) will be parameter-locked. In this mode you can change their values however they will not be affected when you load presets. This way you can audition presets with your mix/dry settings.

ER->LR

Amount of ER output to be sent to LR engine input. Click on a button below to select the pick-up point in ER signal chain. There are 6 points available. Note that [ER OUTPUT] includes the ER Pre-Delay (pre-delay is implemented at the end of the chain).

GAIN [ER/LR]

ER/LR mix balance controls. These 4 controls work in the same way as WET/DRY as 2 linked pairs. The upper [GAIN] control corresponds to the ER, the lower is [LR].
[MUTE] will mute the ER or LR respectively
[ER/LR] is a mix balance in percent (0 = fully ER, 100 = fully LR)
The below control is the combined ER/LR gain. The lock button works like the WET/DRY lock button.

DIFF

ER/LR Diffuser mix gain in %
[DIFF] button turns on/off corresponding ER/LR diffuser

M-DEPTH

ER/LR Modulation depth in %

M-RATE

Modulation rate in Hz

M-RAND

Modulation randomness in %.
0 = the modulation LFOs are SINE waves
100 = the modulation LFOs are more random

NOTE: This control also affects MAT/DCY filters so it's not disabled when modulators are turned off.

[MOD] button turns on/off corresponding modulator

VU Meters

Upper section corresponds to the input/output, while the lower section corresponds to the ER/LR. The upper readout value is the peak level in dB (green color in default color scheme), the lower's is the RMS level in dB (violet color).