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USER MANUAL

VORTEX Downmixer — User Manual

Manual version v0.4.6 · August 2026

Contents · 18 sections

VORTEX Downmixer — User Manual

Manual version v0.4.6 · August 2026 · Kaizen Audio


Contents

  1. Introduction
  2. System requirements
  3. Installation
  4. Licensing: trial, activation and deactivation
  5. Quick start
  6. The target is the output bus
  7. Input formats and Input As
  8. The interface, zone by zone
  9. The group controls
  10. LFE, stereo and mono
  11. Dialog protection and the limiter
  12. Recovery Lock
  13. The radar (visualizer)
  14. Presets and A/B comparison
  15. Settings (the gear)
  16. DAW notes and known limitations
  17. Troubleshooting
  18. Specifications

1. Introduction

VORTEX Downmixer takes an immersive or multichannel mix and folds it down: any of nine supported formats — from 5.1 up to 9.1.6 — into any smaller format, all the way to stereo and mono, collapsing the Atmos height layer properly.

The fold is the ITU-R BS.775 matrix, used verbatim, with no house seasoning. That is where its defining feature comes from:

Recovery-Lock

When you deliver an immersive mix, sooner or later somebody folds it to stereo: a living-room TV, a pair of headphones, the broadcast chain. The player does that with the ITU coefficients. Most downmixers interpret those coefficients — their own auto-gain, their own compensation, their own colour — and what comes out is no longer the standard.

VORTEX uses the exact ITU table, the same one the AXIS Upmixer assumes. In practice that means the downmix VORTEX produces can be re-expanded by AXIS. You can fold to stereo, send that stereo down whatever chain you like, and expand it back into the room with the field recovered. It is a round-trip guarantee, and you can see it at all times: the RECOVERY LOCK indicator tells you whether you are still standing on the standard or you have started making your own decisions.

No auto-gain. No hidden compensation. Every factory value is transparent: with everything at its default, VORTEX performs exactly the fold the standard describes and nothing else. Anything creative is your decision — visible, and one click away from being undone.

What goes in and what comes out

  • Input: 5.1 · 7.1 · 5.1.2 · 5.1.4 · 7.1.2 · 7.1.4 · 7.1.6 · 9.1.4 · 9.1.6.
  • Output: any format on that list smaller than the input, plus stereo (Lo/Ro or Lt/Rt) and mono.
  • Plug-in formats: AAX (Pro Tools), VST3, AU (Logic) — macOS only.

2. System requirements

Operating systemmacOS 12 (Monterey) or later
ProcessorApple Silicon or Intel (native universal binary)
FormatsAAX · VST3 · AU (AUv2)
Pro Tools12.8.4 or later
Sample rates44.1 / 48 / 88.2 / 96 / 192 kHz
iLokNot required. VORTEX is activated with your Kaizen Audio account — no iLok account, no iLok License Manager, no USB key
InternetRequired to activate your licence (offline activation using a second, connected computer is available — see 4.4)

There is no Windows build.


3. Installation

3.1 Installing

  1. Download the VORTEX Downmixer installer from your Kaizen Audio account.
  2. Double-click the .pkg. The installer is signed and notarized by Apple, so macOS raises no security warnings.
  3. Follow the steps: Introduction → Read Me (what’s new in this release) → Licence (end-user agreement) → Installation Type.
  4. On the Installation Type screen you can uncheck any format you don’t use. All three are installed by default:
FormatInstalled to
Pro Tools AAX/Library/Application Support/Avid/Audio/Plug-Ins/Kaizen Audio/VORTEX Downmixer.aaxplugin
VST3/Library/Audio/Plug-Ins/VST3/Kaizen Audio/VORTEX Downmixer.vst3
Audio Unit/Library/Audio/Plug-Ins/Components/VORTEX Downmixer.component
  1. Enter your administrator password when macOS asks for it and finish the installation.

The Audio Unit is installed at the root of Components/, not in a subfolder. That is deliberate: macOS does not scan brand subfolders there, and Logic would not register the plug-in.

3.2 After installing

  • Restart your DAW so it picks up the plug-in.
  • Pro Tools: if it was open, quit it completely (Cmd+Q) and relaunch — it rescans and validates the AAX automatically.
  • Logic: on first launch macOS validates the Audio Unit. VORTEX appears under Audio FX → Kaizen Audio → VORTEX Downmixer.

3.3 Updating

Install the new .pkg over the old one; there is no need to uninstall first. Your licence, your presets and your settings are untouched. The plug-in itself tells you when a new version is out, with a small card in the bottom-right corner (Update Now opens the download in your browser — nothing installs itself, and Do not show again silences it).

3.4 Uninstalling

There is no uninstaller; it is done by hand. Delete the three bundles listed above (they will ask for an administrator password).

If you have other Kaizen Audio plug-ins installed, do not delete the whole Kaizen Audio/ folders — only the VORTEX bundles. And remember: before you retire or wipe a machine, release its activation with Deactivate (4.5).


4. Licensing: trial, activation and deactivation

VORTEX is licensed through your Kaizen Audio account. No iLok, no serial numbers to type: activation happens in your browser.

4.1 What happens the first time

If you insert VORTEX without a licence, the activation panel opens by itself over the plug-in and cannot be closed until you activate. While the plug-in is not activated it runs in demo mode: audio passes cleanly for 5 seconds, then goes silent for 3, over and over. If you hear those periodic dropouts, nothing is broken — it just needs activating.

The panel appears the first time your DAW starts audio with the plug-in inserted, not necessarily when you open the window.

4.2 Activating (online)

  1. Click Activate your plugin, then Let’s go!.
  2. Your browser opens at kaizen.audio. Sign in and, from the side menu of your user account, assign your licence — or request the trial if you haven’t bought yet.
  3. Go back to your DAW. The panel closes on its own and the audio is clean within 5 seconds, with nothing to restart.
  4. Check the status on the licence pill in the plug-in’s footer: green LICENSED. Clicking it opens the ABOUT panel (4.8) with all of your activation details.

If the browser doesn’t confirm within about 4–5 minutes, the panel shows Timed out, please try again! — just repeat the process.

4.3 The trial

The trial is the complete plug-in, with no limitations on the sound, for 30 days. While it runs, the footer pill sits at amber TRIAL and the activation panel shows an orange Trial valid until <date> line. When it expires, VORTEX returns to demo mode (3-second dropouts) and the panel reappears so you can enter a full licence.

4.4 Offline activation (computer without internet)

If your studio machine is isolated from the network, click the Offline Activation link on the Activation screen:

  1. Step 1 — Generate Machine File: save your machine’s identifier file (vortex-downmixer_OfflineActivation.dt, on the Desktop by default).
  2. Step 2: the panel shows the address to go to — www.kaizen.audio/?mb_intent=activate_product — as a link: if that machine has a browser and a connection, one click opens it. If it is off the network, take the file (USB) to any connected computer and go to that same address there. Upload it and download your licence file (.mb).
  3. Step 3 — Last step: back in the studio, drag the licence file onto the marked area of the panel (or double-click that area to find it with the file browser).

Licences activated offline never connect to the internet again.

4.5 Deactivating / moving to another computer

Your licence covers up to 2 of your own computers (one licence per person). To release a machine:

ABOUTMANAGE LICENSE → red Deactivate button.

  • Requires an internet connection (it tells the server that machine is free again).
  • It deletes the local licence; the plug-in returns to its unactivated state.
  • Important: always deactivate from the button, never by deleting files or wiping the drive — if you remove the local licence without deactivating, that machine still counts as occupied. If that happens, contact support to release it.
  • Licences activated offline have no Deactivate button: to move those, handle it from the website or through support.

4.6 Day-to-day use and working offline

With an online licence, VORTEX revalidates with the server occasionally and silently. If your machine goes offline (or a proxy/VPN gets in the way), the plug-in keeps working normally for a 14-day grace period, telling you on screen when the deadline is. Get back online at any point before that date and the count resets by itself.

On top of that, once VORTEX has recognised your licence in a session, it will not mute itself for the rest of that session, whatever happens to the network. A connection problem cannot cut your audio mid-mix.

4.7 One Mac, two activations (the Rosetta case)

If you use the plug-in in a native Apple Silicon DAW and also in one running under Rosetta, each mode keeps its own activation — you may be asked to activate twice on the same Mac. That is expected.

4.8 The ABOUT panel

Click the licence pill in the footer and the ABOUT panel opens. It is where everything about your copy of the plug-in lives:

  • The installed version.
  • Your licence status: the same pill, green LICENSED or amber TRIAL.
  • The e-mail on your account and your License ID (both selectable — if you write to support, copy them from here).
  • An Update to vX available link when there is a new version. It takes you to the download in your browser; nothing installs itself.
  • The MANAGE LICENSE button, which opens the activation panel: activation, offline activation and Deactivate (4.5).

CLOSE dismisses the panel and returns you to the plug-in. Nothing in here touches the audio.


5. Quick start

  1. Insert VORTEX on your multichannel track, choosing the plug-in variant whose output is the format you want: in Pro Tools the plug-in list offers the variants for a 9.1.6 track (9.1.6 → 7.1.4, 9.1.6 → 5.1, 9.1.6 → Stereo…). In other DAWs the plug-in adopts the bus format.
  2. Look at the footer. That is the route it settled on: 9.1.6 ▸ 2.0 LoRo. Source on the left, target on the right. If that isn’t what you expected, the thing to fix is the bus, not the plug-in.
  3. Activate if this is your first time (section 4).
  4. Check RECOVERY LOCK: gold means you are delivering the exact ITU fold. You’re done — the plug-in doesn’t need you to touch anything.
  5. If you do want to shape it, the group knobs in the centre are the place. Each one shows you the actual gain the fold applies to that group of channels, and a double-click returns it to the standard’s value.

VORTEX adds no latency unless you switch on the LIMITER, and in that case it reports it to the DAW, which compensates automatically.


6. The target is the output bus

VORTEX has no “target format” menu. The target is whatever the host asks for: it is negotiated through the plug-in’s output bus.

In practice: insert VORTEX and pick the variant or bus configuration whose output is the format you want. VORTEX reads the input format from the track and folds to whatever the output is.

The footer always tells you what it decided:

9.1.6  ▸  2.0 LoRo

Which pairs are valid

The target has to be strictly smaller than the source, and it cannot gain anything the source doesn’t have: wides, rears and height channels can only stay the same or decrease. So 5.1.4 → 5.1.2 is valid; 7.1 → 5.1.2 is not (it would have to invent a height layer).

That rule yields 32 valid multichannel pairs, plus stereo and mono from any of the nine sources.

VORTEX always resolves the fold in a single pass, straight from source to target. It does not chain formats internally.


7. Input formats and Input As

Nine formats, the same set as the AXIS Upmixer:

FormatChannels
5.16
7.18
5.1.28
5.1.410
7.1.210
7.1.412
7.1.614
9.1.414
9.1.616

A stereo input is accepted as a test bench, but there is nothing to fold: only the L/R group appears.

When the channel count is ambiguous: Input As

Some channel counts fit two formats: 8 channels could be 7.1 or 5.1.2; 10 could be 5.1.4 or 7.1.2; 14 could be 9.1.4 or 7.1.6. If your DAW delivers the bus with a name, VORTEX reads it and there is no ambiguity. If it delivers loose channels, VORTEX has to guess from the count, and its default guess is 7.1, 5.1.4, 7.1.4, 9.1.4 and 9.1.6 respectively.

The Input As parameter overrides that guess. It is a host parameter — it shows up in your DAW’s parameter list, has no on-screen control, and is not automatable.

When the format has been forced or resolved by channel count, the footer marks the source with an asterisk:

7.1.4*  ▸  5.1

Input As is deliberately kept out of presets: it describes your session’s routing, not your fold.

A note on channel names. In the .2 formats, the height pair is the top side pair; VORTEX labels them Tml / Tmr on the meters, while Pro Tools and other hosts call them Top Side. Same pair.

A note on Reaper. Unnamed multichannel buses (loose channels) are accepted in the VST3 build only. AU and AAX take named formats only.


8. The interface, zone by zone

Three columns: input meters on the left, radar and controls in the centre, output meters and limiter on the right. Preset bar on top, status bar at the bottom.

The window has two fixed widths: one for formats without height, a wider one for formats with height (which show two radars). Hiding a control never changes the window size.

ZoneWhat’s there
Preset bar< > to step, preset menu, SAVE, and the A / COPY / B slots
IN (left)Meters for every input channel + input trim
CentreRadar (GROUND, plus CEILING for height formats), group knobs, LFE and stereo menus, and the RECOVERY LOCK indicator
OUT (right)Output channel meters + output trim + the LIMITER block
Status barActive route (9.1.6 ▸ 2.0 LoRo), CPU, licence pill (clickable → ABOUT panel) and version

The meters

They run from −60 dBFS to 0 dBFS: gold up to ≈ −18, amber to ≈ −9 and red above that.

  • The input meters show every source channel and are measured after the input trim and before the group knobs: what you read is exactly what the fold is about to receive.
  • The output meters are measured on what actually leaves the plug-in — after the fold, the output trim and the limiter. Their labels are M for mono, Lo/Ro for stereo, or the target format’s channel names.

The order of the input columns is chosen in the settings: FILM (the Pro Tools visual order — L, C, R, the wides, the sides, the rears, the LFE, then the height layer; this is the factory setting) or SMPTE (bus order, 1:1). It is presentation only: it never touches the audio, and it does not affect the output meters.

The IN and OUT trims

Drag vertically on the meter rail itself to set the trim; the translucent cap shows you the value. Double-click returns it to 0.0 dB. Both share the same range and taper, so 0 dB sits at the same height on both rails.

Both are at 0 dB from the factory and transparent there. Either one off 0 breaks RECOVERY LOCK.


9. The group controls

This is the heart of the plug-in. There is one knob per channel group present in your input format: L/R, C, SIDE, REAR, WIDE, TOP F, TOP M, TOP R. Groups your format doesn’t have simply don’t appear.

At a glance: the knob is not an offset, it is the fold. This is what throws people the first time. In almost every plug-in, a knob at “0” means “I’m not doing anything”. Not here: each knob shows you the absolute gain the ITU fold applies to that group, as it is, in dB.

Fold a 7.1.4 to stereo and you’ll read this:

GroupReads
L/R0.0 dB
C−3.0 dB
SIDE−3.0 dB
REAR−6.0 dB
TOP F / TOP R−6.0 dB

That is the ITU-R BS.775 matrix, on screen, in dB. The plug-in is not attenuating anything on its own: folding two channels into one requires sharing energy out, and those are the standard’s numbers. Think of it as the fold’s mixer, with the faders already set where the standard says.

When you turn a knob, you move the fader from there. And a double-click (or Alt-click) returns it to its ITU value.

You can also type an absolute value straight onto the knob.

When the target is a format rather than stereo

If you fold to another multichannel format, the channels that pass straight through read 0.0 dB — because that is what the fold does to them: nothing. It is the correct value, not a bug.

But note: 0.0 dB means “I’m not touching this group”, not “this knob is disconnected”. Turn it and you are attenuating or boosting that group before it goes out. That is the plug-in’s creative headroom, and it’s what it’s there for.

Range

Each knob runs from −60 to +12 dB relative to its ITU value, and at the bottom of its travel it mutes the group entirely. Any knob off its factory value breaks RECOVERY LOCK.


10. LFE, stereo and mono

10.1 The LFE menu

The LFE OFF / LFE → MAINS menu only matters when the target has no LFE channel — that is, stereo and mono.

  • LFE OFF (factory) — the LFE does not enter the fold. That is what the standard says: its coefficient in the ITU matrix is zero.
  • LFE → MAINS — the LFE is folded into the main channels.

When folding to a multichannel format, the LFE passes through discretely on its own channel and this menu is ignored (it greys out).

With LFE → MAINS, the LFE GAIN knob appears: 0 to +12 dB, +10 dB from the factory. That +10 is not arbitrary — the LFE is stored around 10 dB below the main channels and the player gives it back on playback. Fold it in without that boost and the low end buries itself.

LFE → MAINS breaks Recovery-Lock on stereo and mono targets, precisely because the ITU matrix excludes the LFE.

10.2 The two stereo modes

STEREO LoRo (factory) is the literal ITU fold. It is mono-compatible and it keeps Recovery-Lock. It is what you want 95% of the time.

STEREO LtRt · 90° produces an Lt/Rt-style encode in the Pro Logic II tradition: instead of sharing the surrounds evenly across both sides, it puts them out of phase so a compatible decoder can pull them back out into the room. It is the option for deliveries that will pass through a matrix decoder. It adds no latency.

It can only be selected with a stereo target and an immersive source; in any other case the menu greys out.

LtRt is not mono-compatible and it turns Recovery-Lock off. Summing Lt and Rt to mono cancels the out-of-phase surrounds. On top of that, the encode is pending validation against a real Pro Logic II decoder: treat it as an Lt/Rt-style encode, not a certified one.

10.3 Mono mode

This is a host parameter (no on-screen control, but automatable), with two options:

  • Derived (0.5 LoRo) (factory) — mono comes from the sum of the two Lo/Ro channels at half level. Correlated content living in the centre keeps its level, with no risk of clipping.
  • BS.775 Table 2 — the standard’s direct-to-mono row, which is asymmetric: it sends the centre channel through at full level and leaves the surrounds 3 dB below where they land in stereo. This is the one for when dialogue has to win over everything else. When it is active the footer shows MONO T.2.

Both are published rows of the standard, so neither breaks Recovery-Lock.

Mono is always derived from the Lo/Ro fold, never from Lt/Rt — summing Lt and Rt would cancel the surrounds. That protection is structural: there is no way to get it wrong.


11. Dialog protection and the limiter

11.1 DIALOG

The DIALOG knob (0–100%) appears when you fold an immersive source to mono, or to stereo in LoRo.

Folding squeezes a whole room into two channels, and the first casualty is dialogue intelligibility: effects, music and ambience end up competing with the voice in the same place. DIALOG ducks everything that is not the centre channel, following the envelope of the source centre. When there is dialogue the room steps aside; when there isn’t, it comes back.

Maximum travel is 6 dB of attenuation at 100%. At 0% it does absolutely nothing and Recovery-Lock holds.

It is a delivery tool, not an effect: use it when the fold has to survive a desktop or television listen, and leave it at 0 when you deliver the reference downmix.

11.2 LIMITER

LIMITER is the true-peak overload protection. It is off from the factory and opt-in on purpose: with it off, the plug-in is a pure fold with no latency, and that is exactly what keeps the result bit-exact.

Switch it on when the fold sums past what your delivery allows — folding adds energy, and an immersive mix that respects its own ceiling can overshoot when you collapse it.

  • Ceiling: −24.0 to 0.0 dBTP, −1.0 dBTP from the factory (the usual margin for lossy encoding).
  • The GR bar shows the gain reduction being applied, full scale at 12 dB. It reads off when the limiter is off.
  • Latency is only declared while it is on (128 samples, about 2.7 ms at 48 kHz), and your DAW compensates for it. With it off, the plug-in’s latency is zero.

Switching it on breaks Recovery-Lock, by definition: if the limiter acts, you are no longer delivering the matrix.


12. Recovery Lock

The wide button under the controls. Two states:

StateReadsWhat it means
GoldRECOVERY LOCK · ITU BIT-EXACTThe effective matrix is the ITU table, exactly. Your downmix can be re-expanded by the AXIS Upmixer.
RedCUSTOM FOLD · RESET TO ITUYou’ve moved something. The fold is yours now, not the standard’s.

Red is not an error — it is information. There are deliveries where you want to make the calls. What the indicator guarantees is that you will never ship a tweaked fold thinking it is the standard.

What keeps it gold

All of this at once:

  • the group knobs at their ITU values (all of them),
  • the IN trim at 0 dB,
  • the OUT trim at 0 dB,
  • LFE OFF (on stereo and mono targets; when folding to a format that has an LFE, the menu doesn’t count),
  • STEREO LoRo (not LtRt),
  • LIMITER off,
  • DIALOG at 0%.

Not involved: mono mode (both of its options are published rows of the standard), the limiter ceiling, Input As, meter order, and the radar settings.

The button also resets

Click it and you’re back to the ITU values — it works in both states. It resets the group knobs, the input and output trims, the LFE mode and gain, the stereo mode, the limiter and DIALOG.

It does not touch mono mode, the limiter ceiling, Input As, meter order or the radar settings. And because it sends the changes to the DAW, your undo works normally.

Check it yourself

You don’t have to take our word for it:

  1. Take a stereo file. Expand it with the AXIS Upmixer. Put VORTEX after it, folding back to stereo, everything at defaults.
  2. Sum the result against the original stereo with inverted polarity.
  3. It nulls.

Measured through the whole chain, that residue sits around −155 dB on 5.1, 7.1.4 and 9.1.6 — silence for all practical purposes. VORTEX’s fold on its own, compared against the ITU matrix computed independently, nulls at −300 dB.

You can run the same test against a third-party reference: fold with VORTEX at factory settings, fold with whatever downmixer you normally use, invert one and sum.


13. The radar (visualizer)

The radar shows the input field — what you are about to fold, not the result. It is the quick way to see what you’re working with: where the energy lives in the room, which speakers are hot, and what you’re about to run over when you collapse it.

Every particle of light is a frequency band placed where it sounds: the angle is the direction in the room, the distance from the centre is concentration (hard against the edge = coming from a single speaker; near the centre = spread across opposite speakers, a diffuse field), and brightness is level.

The little squares around the rim are the speakers of the input format, with their labels, and they pulse with the level of their channel. The LFE gets its own indicator: the horizontal bar under the circle (a channel with no direction can’t be on the radar).

If the input format has height channels, a second radar appears alongside, badged CEILING (the first one is GROUND). Both are the same size as the single radar you get with formats without height.

The gear in the radar’s top-right corner opens the settings, where you choose its look: the drawing style (DROPS, the analytic dust cloud, or TRAY, comets with trails that show movement) and the colour criterion (FREQ colours by frequency, LAYER separates floor from ceiling, 3-BAND is a three-band traffic light).

The radar is not a level meter. For absolute levels, use the column meters.


14. Presets and A/B comparison

The top bar runs the presets:

  • < / > — previous / next preset.
  • Centre menu — all your presets, with subfolders as submenus.
  • SAVE — save with a name and a folder. You can create a new folder from the same dialog. If the name already exists, it asks before overwriting.

A preset stores your fold: the group knobs, the trims, the LFE, the stereo mode, the mono mode, DIALOG and the limiter. It does not store the radar’s look, the meter order or Input As — those are your preferences and your session’s, not your fold’s. That way you can share presets without dragging your visual setup along, and load someone else’s without having yours changed.

Your presets live in ~/Documents/VORTEX Downmixer/Presets/ (.vortexpreset files), and the subfolders in there are the folders in the menu. Copy them, back them up or move them to another machine as ordinary files. To delete one, remove the file in the Finder. The folder is created the first time you save.

A / COPY / B

Two complete memories for comparing settings:

  • A and B — switch between the two memories. The current state is stored in the one you leave, and the other one is recalled. Both start empty; recalling an empty one changes nothing.
  • COPY — copies the current state into the other memory and jumps to it: the perfect starting point for “the same, but with this one knob different”.

Two details: the A/B slots live in the window and are lost when you close it; and unlike presets, they store the complete state, visual preferences included — so jumping between slots can also change the radar’s look.


15. Settings (the gear)

The gear in the radar’s corner opens a panel with eleven settings. Changes apply live: ACCEPT keeps them, and CANCEL, ESC or a click outside reverts them all.

SectionSettingRange (factory)What it does
SCOPEMODEDROPS / TRAY (DROPS)Drawing style: analytic dust cloud, or comets with trails
DENSITY10–100% (50)How much light the cloud carries
SPEED0–100% (30)Size and softness of the dot: low = fine grain; high = diffuse specks
DECAY0–100% (50)How long the trail persists
THRESHOLD−100…−30 dB (−80)Sensitivity: high = only loud material; low = you see the room’s air
COLOURFREQ / LAYER / 3-BAND (FREQ)Colour criterion
BLUR0–100% (20)Defocus
WHITE FADE0–100% (30)Rescues colour when the cloud piles up and washes out to white
TINT0–100% (50)Saturation
TRAY LEN1–10 (5)Trail length in TRAY mode (no effect in DROPS)
METERSORDERSMPTE / FILM (FILM)Column order of the input meters

Everything in this panel is a preference of your machine, not of the project: it doesn’t travel in presets and doesn’t appear in DAW automation, but it is saved with the session.


16. DAW notes and known limitations

Pro Tools

Native AAX, Pro Tools 12.8.4 or later. This is the plug-in’s reference host. Each source→target pair is offered as a separate variant when you insert it. After installing or updating: Cmd+Q and relaunch (Pro Tools caches the plug-in list between launches).

Logic

Via Audio Unit, under Audio FX → Kaizen Audio. Which multichannel formats are available depends on your version of Logic.

Nuendo / Cubase / Studio One

Via VST3, with named buses.

Reaper

Unnamed multichannel buses are accepted in VST3 only; with named buses it works as it does in any other host. Bear in mind that when the bus arrives unnamed, VORTEX infers the format from the channel count — use Input As if your count is ambiguous (section 7).

Known limitations

  • Don’t chain two instances through a format with height. Folding 9.1.6 → 7.1.4 → 2.0 across two instances is not the same as folding 9.1.6 → 2.0 directly: splitting or merging the height layer shifts correlated material by around 3 dB one way or the other. It is a property of the fold, not a defect — the supported workflow is one instance, one direct fold, which is also what guarantees Recovery-Lock.
  • LtRt is not mono-compatible and is pending validation against a real Pro Logic II decoder.
  • macOS only. There is no Windows build.
  • 9.1.2 is not supported: it doesn’t exist as a native bus format in Pro Tools Ultimate and has no equivalent in the format set DAWs use.

17. Troubleshooting

The activation panel covers the interface and won’t close. There is no licence or trial active on this machine. Activate from the panel, or request the trial in your Kaizen Audio account. Section 4.

The audio drops out for 3 seconds every so often. Same cause: the plug-in isn’t activated (or the trial expired).

The AAX won’t load in Pro Tools. Check that you installed the AAX from the official package and that your Pro Tools is 12.8.4 or later, then quit Pro Tools completely (Cmd+Q) and relaunch so it rescans. Last resort: delete ~/Library/Preferences/Avid/Pro Tools/InstalledAAXPlugIns and let it rescan.

Logic can’t see the plug-in. The Audio Unit has to sit at the root of /Library/Audio/Plug-Ins/Components/. The installer puts it there; if you moved it into a subfolder, move it back. Restarting the Mac forces an Audio Unit rescan.

The footer shows a source format that isn’t mine. The channel count is ambiguous and the bus arrived unnamed. Set Input As from your DAW’s parameter list. The asterisk in the footer means exactly that: the format was inferred or forced. Section 7.

All the group knobs read 0.0 dB. You’re folding to another multichannel format and those channels pass straight through — 0.0 dB is correct. Fold to stereo and you’ll see the ITU values.

RECOVERY LOCK is red and I didn’t touch anything. Something is off its factory value: a trim, LFE → MAINS with a stereo or mono target, LtRt, the limiter or DIALOG. Click the button to return to the ITU values in one go. Section 12.

The fold doesn’t null against the AXIS Upmixer. Check that RECOVERY LOCK is gold in VORTEX and that AXIS is in a mode with Downmix Lock (any but EXTREME) with its mixer untouched. A tweak at either end breaks the identity.

“Online validation failed” on screen. The plug-in can’t reach the server (no internet, VPN, proxy?). You have 14 days of grace with the date on screen; get back online before then. Section 4.6.

I want to move my licence to another Mac. On the old machine: licence pill → ABOUTMANAGE LICENSEDeactivate. Then activate on the new one. Section 4.5.

Support: hello@kaizen.audio — write from your account e-mail and include the plug-in version, your DAW and your system. Error messages in the licence panel can be selected and copied directly.


18. Specifications

Inputs5.1 · 7.1 · 5.1.2 · 5.1.4 · 7.1.2 · 7.1.4 · 7.1.6 · 9.1.4 · 9.1.6
OutputsAny format on that list smaller than the input (32 pairs), plus stereo (Lo/Ro and Lt/Rt) and mono
Recovery-LockBit-exact ITU-R BS.775 fold at factory settings; verified at −300 dB against the independently computed matrix, and at −155 dB through the full chain with the AXIS Upmixer
Latency0 samples. With LIMITER on: 128 samples (2.7 ms @ 48 kHz), reported to the DAW and compensated (PDC)
Sample rates44.1 – 192 kHz
AutomationAll mix controls; Input As and the display preferences are deliberately excluded
Presets~/Documents/VORTEX Downmixer/Presets/ (.vortexpreset), with subfolders
FormatsAAX · VST3 · AU — macOS 12+, universal (Apple Silicon + Intel), signed and notarized by Apple

VORTEX Downmixer is a Kaizen Audio Group SL product — kaizen.audio Designed by sound engineers, for sound engineers. Dolby and Dolby Atmos are trademarks of Dolby Laboratories. Pro Tools and AAX are trademarks of Avid Technology. All trademarks are the property of their respective owners.