Installation

Fusor Studio runs on Windows 10 or later. macOS support is planned but not yet shipped.

Getting connected takes three steps: set up the MIDI bus, import the mapping file for your DJ app, and install Fusor Studio.

Prerequisites

Windows 10 or later (macOS support planned).
A DJ application. Traktor Pro and Mixxx are supported. djay Pro and Virtual DJ are in progress.
A virtual MIDI loopback driver. Fusor Studio communicates with your DJ software over MIDI. On Windows the recommended one is loopMIDI; Windows MIDI Services with a FusorBus loopback endpoint becomes preferred once its outstanding interoperability problem is fixed (see below).

Set up the MIDI bus

Fusor Studio talks to your DJ software over a virtual MIDI port. You need to create that port before either side can connect.

loopMIDI is the supported default today. Either bus works, since Fusor Studio just opens a port by name, but Windows MIDI Services has an interoperability problem that can leave Fusor Studio unable to send after you restart your DJ app (I-018 in Troubleshooting). Use loopMIDI until we announce otherwise. The WMS path is documented below for users who want it.

loopMIDI (current default)

Download and install loopMIDI (Tobias Erichsen).
Launch loopMIDI.
In the port name field, create one port named FusorBus (the name is your choice — pick something memorable and use the same name in the DJ app and in Fusor Studio).

Fusor Studio uses a single bus in both directions. Fusor sends on MIDI channels 1–8 and receives telemetry on channels 9–16 over the same port, so one virtual port is all you need.

Leave loopMIDI running whenever you use Fusor Studio. You can set it to auto-launch with Windows in its own settings.

FusorBus on Windows MIDI Services (preferred once stable)

Windows MIDI Services is Microsoft's new MIDI 2.0 stack. It will become the preferred bus once I-018 is resolved upstream, because it gives Fusor Studio a modern endpoint and a dedicated MIDI Settings app for inspection.

Install the latest Windows MIDI Services release from Microsoft's downloads page.
Open the MIDI Settings app (ships with WMS).
Create a loopback endpoint named FusorBus.
Confirm it appears in the endpoint list as active.

Import the mapping file for your DJ app

Fusor Studio drives your DJ software through a MIDI mapping file made for that app, the same idea as a hardware controller's factory mapping but delivered as a file you import. The mapping is distributed as a file you download from the Fusor downloads page rather than one bundled inside the application folder; the same downloads page carries the mapping file for every supported DJ app. Import it into your DJ app before you install Fusor Studio itself.

Traktor Pro uses a Traktor Settings Import (TSI) file, Fusor.tsi:

Download the Fusor mapping file for Traktor Pro from the Fusor downloads page.
In Traktor's Preferences > Controller Manager, click Import... (or Add... > Import).
Select the downloaded .tsi file.
Verify the port assignments are still set correctly after import.

The mapping covers EQ, volume, crossfader, FX units, stems, tempo, and the telemetry Traktor sends back to Fusor Studio. Traktor Pro Setup covers the MIDI port configuration this mapping needs and the rest of Traktor-specific setup.

If you would rather build a mapping by hand, or check what a particular control expects, Teach Mode emits one control at a time so your DJ app's MIDI Learn can pick it up.

Install Fusor Studio

Download the latest Fusor Studio installer.
Run the installer and follow the prompts.
Launch Fusor Studio.

On first launch, Fusor Studio creates a folder at Documents/Fusor/ containing subfolders for your fusors, actions, step sets, collections, and packs. They start empty; Guided Setup's first screen is where you confirm the location and, if you want them, add the example files.

That installer is the only one you download by hand. From then on Fusor Studio finds new builds itself and installs them when you restart. See Updating Fusor Studio.

Connect Fusor Studio — use Guided Setup

Open the App menu in the top-left of the player and choose Settings... (or press Ctrl+,). Settings opens on the Guided Setup tab, which walks the whole connection in four groups: MIDI bus, DJ app, Controller, Test. Every screen has a Skip button, so you can move past anything that doesn't apply.

Guided Setup is the recommended path. It covers the same four settings you would otherwise set by hand on the Connection tab:

Setting	What it does
Fusor MIDI Bus	The virtual port you created above. One bus in both directions: Fusor sends on channels 1–8 and receives telemetry on channels 9–16. Use Rescan if a bus you just created isn't in the list.
DJ Application	Sets the control mapping and how Fusor reads your control state. Have the DJ app open before you pick it.
Deck Pair	The two decks Fusor automates. Everything a fusor drives is resolved against this pair.
Capture Control State	Asks the DJ app where its controls currently sit, and uses the answer as the baseline for the transition.

Control State Capture is required

Fusor Studio will not arm or start a transition until it has captured your control state. If it hasn't, the status line reads UNCAPTURED and the arm control is refused.

Selecting or changing the DJ application starts a capture. On Traktor there is one extra wrinkle: the startup capture sits behind a Capture button rather than running on its own, because Traktor answers by sending back the position of every control and that can produce a brief audio glitch. If Traktor wasn't open when Fusor Studio launched, open Settings → Connection and click Capture Control State once it is.

If capture can't reach the DJ app at all, you can still run transitions by hand — see Blind Mode.

Settings... is disabled while a transition is running and reads Settings... (locked while running). Finish or abort the transition to reopen it.

Next steps

Continue to Traktor Pro Setup to connect Fusor Studio to your DJ software, then start the Tutorials — they walk you from first launch to your first transition and on to authoring.