Connecting Studio One, QLC+, and Enttec Open DMX in Windows 11

If you are trying to automate a live light show from your DAW, legacy tutorials will tell you to install Tobias Erichsen's loopMIDI. However, if you are running a modern Windows 11 build, you have likely found that your virtual ports have stopped communicating.

This breakage happens because Microsoft rolled out the new Windows MIDI Services architecture. This updated framework conflicts directly with legacy, third-party virtual drivers like loopMIDI and virtualMIDI. Instead of fighting the deprecated drivers, the solution is to route PreSonus Studio One data directly into QLC+ using Microsoft's native loopback mechanisms, then output via your Enttec Open DMX interface.

Why the Hardware Dictates Using QLC+

Understanding your hardware architecture explains exactly why this specific software pipeline is necessary. The market features two primary variants of this interface, and they handle data entirely differently:

• Enttec Open DMX USB: A passive, budget-friendly interface. It contains a basic USB-to-serial chip but no onboard microprocessor to handle DMX frame timing. Because of this high software overhead, proprietary platforms like Enttec's own EMU software explicitly refuse to support it.

• Enttec DMX USB Pro: An active interface containing an internal microprocessor and frame buffer. It regulates DMX timing entirely on the hardware layer, ensuring a steady signal even if the host PC encounters a CPU spike.

Because proprietary platforms lock out passive hardware, QLC+ is essential. It is one of the few stable, open-source engines capable of generating software-side DMX frame timing directly for the Open DMX box, giving you professional timeline automation without forcing an expensive hardware upgrade.

Prerequisite: Install Windows MIDI Services

The new native MIDI stack does not come pre-activated out of the box in standard Windows 11 installations. You must install the runtime and core configuration components manually before proceeding:

• Navigate to the official Microsoft GitHub repository (microsoft/MIDI).

• Download and install the latest Windows MIDI Services Runtime installer by click on the latest release, and scrolling to the bottom.

  

• Launch the newly installed MIDI Settings app from your Start menu to confirm the ecosystem is active.
  

The Precision Routing Pipeline

With the native architecture installed, follow these steps exactly to build the automation pipeline. Misordering the configuration can cause the DAW to lock up the virtual port before the lighting console can establish a handshake.

Step 1: Create the Native Loopback Endpoint

Open the Windows MIDI Settings application. Navigate to the Loopback section and create a new MIDI Loopback Endpoint. This creates a unified virtual patch cable handled directly at the system kernel level.

Step 2: Configure Studio One Output

Open PreSonus Studio One. Go to Studio One > Options > External Devices. Click Add... and select New Instrument (do not select a keyboard, as we are transmitting data out, not taking inputs). Name the device QLC+ Transmitter. In the Send To dropdown menu, select your newly created Loopback port (A).

Step 3: Connect your Enttec Open DMX USB interface to the computer.

Step 4: Bind Inputs and Outputs in QLC+

Launch QLC+. Navigate to the Inputs/Outputs tab and highlight Universe 1. On the left panel (Mapping/Input), locate your Loopback (B) and drag that onto Universe 1. On the right panel (Output), locate your Enttec Open DMX device and drag that onto Unverse 1 as well. Note that how the Loopback works is that whatever is send to (A) is received in (B) and vice-versa. This is the reason why we're using different loopback ports in Studio One vs. QLC+.

Now you can automate with instrument tracks in Studio One by sending MIDI CC information directly to your fixtures via QLC+ and Enttec Open DMX.

Technical Notes & Latency Optimization

Because the Enttec Open DMX interface relies completely on your host PC's processor for DMX frame generation, keep your Studio One audio buffer size at a balanced level (such as 256 or 512 samples) during live shows. Setting audio buffers excessively low can cause minor stuttering or flickering in the physical DMX stream if the CPU prioritizes audio processing threads over the DMX frame clock.