What is DMX Host and Listener?

The DMX Host (DMXLHost.exe) and DMX Listener (DMXL.exe) work together to provide a system to read the DMX output from any lighting desk via a TCP/IP network. Together, they can not only display the levels in a DMX stream, but they can also provide complete control of your computer directly from the lighting desk.

DMX Diagnostics

The data that is sent around the venue to control those lights is susceptible to all sorts of problems - unterminated lines causing reflected data packets, sub-standard cable reducing the quality of the signal, old or well used connectors can deteriorate the signal significantly, and maybe the desk itself is sending strange data. DMX Listener enables a technician to see the actual DMX values being sent - either as the actual 0 to 255 DMX data, or as 0 to 100% levels most of us are used to. If placed at the end of the DMX chain, you will be able to diagnose if a fault is at the lantern/dimmer or coming from the desk by bypassing a suspect unit/cable and seeing if the data remains corrupted, or is fixed.

Lighting Designer's Tool

After plotting the show, the Lighting Designer watches many of the subsequent rehearsals so at the he/she can tweak the levels as needed. Unfortunately, the lighting desk is often not easily accessible to see the channel levels, so the DMX Listener can be used by the designer to watch the show levels from anywhere there is either a DMX point, or an Ethernet connection to the computer that is receiving the DMX. Wireless Ethernet would allow the designer to see the status of the desk from anywhere within range.

The software can also take "snapshots" of the DMX data and mark these as cues. This data can be saved as an alternative way to save the show data. Then during show playback, a display shows if the currently output DMX data matches a specific cue - maybe the stage manager will be able to see what lighting cue they are up to. According to the author, a future version is planned to be able to read and save shows into a number of lighting desk formats - making show conversions from one format to another considerably easier.

Show Control

Play CDs, mp3s, control PowerPoint and much more from the lighting desk!!

This is the function that the software was originally designed to perform. Any of the received DMX channels can be allocated to trigger almost any action that the computer can already do. The primary way this is achieved is via a specialised keystrokes system, where any application that can be controlled via keyboard commands can be sent preset commands via levels of specific DMX channels. This obviously requires a little bit of setup, but once the computer knows how to interpret the DMX into keystrokes the rest is easy.

The software also has some other built in show control options, such as direct control over Microsoft PowerPoint presentations. Next and previous slide transitions and jumping to specific slide locations, and even some control over the size and placement of the image within the screen. DMX Listener can also directly play most forms of media including sound files and CDs, fade the audio levels and balance of an installed soundcard, as well as muting the output signal. This combined with direct control over audio file selection and playback puts which can give total control of complicated sound effects options into the hands of the show designer.

Hardware currently supported by DMX Host

Naturally to use this software you must be able to connect your PC to the DMX source.  We have implemented a number of solutions which are listed below, and more will be available in the future.  If you have a specific request, please do not hesitate to contact us.

Hardware Device Interface Description Notes
Manufactured by Soundlight
USB A small and robust device self-powered USB connection.  Easy to setup and reliable. Available for purchase (click here for details).
Note: there may be compatibility problems with this device on any computer that has the software for Martin Light Jockey installed. Also this device requires a POWERED USB port.
Protocol developed by Artistic Licence
Ethernet You can connect directly to any source that uses this protocol This implementation is currently in Beta and so any comments are welcome.  Please consult the information contained in this document for tips in connecting to an existing ArtNet network
LanBox Ethernet
Protocol developed by LanBox
Ethernet Direct connection to any Ethernet-enabled LanBox Device This implementation is currently in Beta and so any comments are welcome. 
Manufactured by Soundlight
Manufactured by Soundlight
Generic RS-485 Other The DMX protocol is actually built around the RS-485 protocol which has many hardware solutions. There are 2 major considerations when going down this path.  Firstly you must make sure that the crystal for your RS-485 card has the correct timing value (4Mhz should do the trick).  RS-485 uses 8-bit data whereas DMX uses 9-bit data.  We have managed to get around this but you MUST have a control channel to ensure the data is in synch.  For reliability we recommend using any one of the other options.