The house lights dim. The audience falls silent. In the control booth, a lighting designer's fingers hover over the console, ready to bring the stage to life. With a press of a button, colors wash across the stage in perfect synchronization. Behind this seamless display of light stands an unassuming box that few in the audience will ever notice: the DMX splitter.
Every night before a show at the Theater, I would walk the stage, checking the daisy chain of lights. For those unfamiliar with stage lighting, DMX (Digital Multiplex) is the language lights speak to understand commands from the control console. Traditionally, these commands flow in a single line:
🟠 Control Console ⮕ Light 1 ⮕ Light 2 ⮕ Light 3 ⮕ ... and so on
This daisy chain configuration works perfectly well for smaller setups. Signals travel from one fixture to the next, with each light passing the message along like a game of telephone. But as productions grew more elaborate, this simple chain began to show its limitations.
During a particularly ambitious production of "A Midsummer Night's Dream," we hit a wall. The designer wanted 40 individual LED fixtures to create a magical forest effect, but our system kept glitching after the 30th light.
"That's when I learned about the '32 fixture rule'," explains veteran lighting technician David. "It's a technical limitation of the DMX protocol - after 32 devices, the signal integrity can't be guaranteed."
The solution came in the form of the Splitter Selective Pro: a professional 11-port splitter with 2 master ports and 9 outputs, featuring RDM capability and customizable operating modes.
The Splitter Selective Pro serves a deceptively simple purpose: it takes the incoming DMX signal and creates multiple identical copies, each capable of controlling its own chain of up to 32 fixtures. Instead of one long, vulnerable chain:
Console → Splitter Selective Pro
🟠 Chain 1 ⮕ Lights 1–20
🟠 Chain 2 ⮕ Lights 21–40
🟠 Chain 3 ⮕ Lights 41–60
This elegant solution not only overcomes the 32-fixture limitation but offers several practical advantages that become clear once you've worked behind the scenes.
On a recent arena tour, our stage featured four towers of moving lights at the corners, a front truss, and additional fixtures scattered throughout the venue. Without the Splitter Selective Pro, our cable runs would have snaked across the stage in a complicated web, creating trip hazards and confusion during setup.
"With the Splitter Selective Pro positioned center stage, we could run direct lines to each section," David notes. "It cut our setup time in half and made troubleshooting infinitely easier."
The clarity extends to the wiring diagram as well:
Console → Splitter Selective Pro
🟠 Tower 1 ⮕ 8 Lights
🟠 Tower 2 ⮕ 8 Lights
🟠 Front Truss ⮕ 12 Lights
Each section receives a fresh, strong signal directly from the source rather than a signal that has traveled through multiple devices.
During a critical moment in a Broadway production, a stagehand accidentally kicked a DMX cable loose from a fixture. Without a quality splitter, this would have disabled every light downstream. But because we had used the Splitter to create separate chains for each section of the stage, only one small area went dark while the show continued.
This built-in redundancy has saved countless performances from technical disasters. The galvanic isolation on all DMX ports of the Splitter Selective Pro ensures that any interference or short circuits on one line won't disrupt the operation of other devices, protecting valuable lighting equipment.
The Splitter Selective Pro comes with various configuration options. The front panel features two 5-pin Thru DMX master ports (A and B) that provide simultaneous input and output, allowing devices to be connected in series. Each of the 9 DMX outputs is equipped with a mechanical switch to select the signal source: either input A or input B.
When selecting a splitter like the Splitter Selective Pro, consider:
The Splitter Selective Pro primarily uses 5-pin XLR5 connectors, but options with 3-pin XLR3 connectors and EtherCON connectors are available for the junior model.
The Splitter Selective Pro offers 9 output ports, each capable of controlling up to 32 devices.
The Splitter Selective Pro not only works with RDM (Remote Device Management) for two-way communication between the console and fixtures but also features intelligent LED indicators that provide visual feedback on the status of DMX lines.
A warning from the trenches: many entry-level splitters feature both 3-pin and 5-pin outputs for each channel. It's crucial not to use both simultaneously for the same output channel.
"I've seen newcomers plug both the 3-pin and 5-pin outputs from the same channel to different fixtures," David cautions. "This creates a Y-cable effect that can cause signal degradation and erratic behavior."
The Splitter Selective Pro avoids this issue with its clear design and operating modes:
Useful for creating a 10-port splitter by cascading multiple devices:
🟠 Switches in "A" position ⮕ Port B becomes an output
🟠 Switches in "B" position ⮕ Port A becomes an output
Both master ports are used as inputs, and the distribution of output ports between channels is set by switches. This mode blocks switching inputs to outputs.
Unlike some technical equipment with strict placement requirements, the Splitter Selective Pro can be positioned wherever it makes the most sense for your setup. Its ergonomic and lightweight 1U rack design (482 x 44 x 110 mm) ensures convenience in transportation and installation. It can be:
🟠 Near the console ⮕ for immediate signal distribution
🟠 Center stage ⮕ for minimal cable runs to various areas
🟠 At the beginning of complex sections
🟠 Mounted in a 19-inch rack ⮕ with other equipment
"I've even placed multiple Splitter Selective Pro units in sequence for particularly complex shows," David shares. "The signal remains clean because each splitter regenerates it before splitting."
The Splitter Selective Pro offers features that go beyond basic signal splitting
Real-time monitoring
Intelligent LEDs provide visual indication of DMX line status. When a line is connected, the LED lights up, and when DMX data is transmitted, it pulses. When RDM frames are detected, the LED adds yellow-orange flashes.
RDM filtering
Mechanical DMX/RDM or DMX Only switches allow selective disabling of RDM, minimizing the risk of failures and increasing system reliability.
Synchronous operation
Data processing and switching is performed "on the fly" with minimal transmission delays (at the level of microseconds), preventing temporal desynchronization of slots in streams and eliminating stroboscopic effects.
Instant startup
The device startup time is just 0.5 seconds.
Wide operating temperature range and overvoltage protection
The splitter operates from 0 to +60°C and is powered from a 100-277V (50/60Hz) network via a PowerCON TRUE1 connector. Each port has galvanic isolation (5000V rating) and protection against voltage surges using TVS diodes.
The Splitter Selective Pro may not have the flash of moving lights or the prominence of a lighting console, but it's the unsung hero that makes complex lighting designs possible. By implementing this professional device, lighting designers can create more elaborate, reliable, and organized systems that bring their creative visions to life.
The Splitter Selective Pro optimizes wiring, speeds up setup, and eliminates equipment placement restrictions for clubs, bars, stages, and touring productions. Despite its high efficiency, performance, and safety, this splitter remains the lightest professional selective device in its class.
Next time you're captivated by a perfectly synchronized lighting display, remember the small box behind the scenes that made it all possible: the Sundrax DMX Splitters.
