Merger MD 11U

2 DMX512 lines with HTP connection

The MD11 connects two DMX512 lines with 512 channels each to one single line. The same channel of both lines is connected in accordance with HTP (highest takes precedence). Example: channel 1, line A with channel 1, line B, etc.

The MD11 can be used for mixing the DMX512 data of two mixing consoles with shared priorities, for managing the backup of two DMX512 lines and for processing the DMX512 timing when using difficult utilities.

As far as backup-managing is concerned, the MD11 versions 2.0 and above dispose of two function modes for the case of interface failure.

1) If only one input is in use during an interface failure, the latest data of this input are held until one of the inputs (A or B) can recognize a DMX signal again.

2) Both lines receive a DMX512 signal, but all data at the input B (slave) equal zero. In case of an interface failure, the latest data of input A (master) are held until three seconds after at least one value of input B has become
unequal 0.


Example for 2:

The main console (on A) is operating, the backup-console is connected, and the master fader is set to 0%. In case of a function failure of the main console, the MD11 will keep the latest values. The present setting can now be prepared as good as possible in the backup-console before opening the master fader to 100%. Only after having recognized at least 1 channel > 0, three seconds will pass before the MD11 will switch from the buffer to the backup-console and send the values from here to the output.

The MD11 can also perform signal processing, because both inputs can easily process a quick DMX timing with potentially varying parameters, while the output provides a stable and only slightly slower signal, which has so far been accepted by all connected utilities.

MD 11U


  • galvanic isolation of the input and output
  • both inputs are terminated with 120 ohm resistors
  • input A is located close to the output in case of power failure
  • DMX512 processing delay of maximum 1 frame
  • (depending on the timing of the input signal)
  • also available as SNAP-IN for DIN-rail mounting (image)
  • offset of one line available upon request


Timing IN A oder IN B IN A und IN B
Break 95 µs 95 µs
MAB 18 µs 25 µs
B2B 28.1 ms 30.8 ms
Upd/s 35  32




Size: 200 x 110 x 50 mm

Weight: 820 g