I'd like to find a simple way to control the lights in our local theater. We have panels and everything, but I'd to experiment with the way I can control the colors of the lights. I'm a web developer and interface designer by profession, so I'd like to 'design' a Web-like interface for this.

Now I wonder: could it be possible to use the audio-out of my computer and/or telephone to send a DMX512 signal?

Every 'command' could be a 'pre-recorded' sound, stored in a WAV. "Dimmer Number 5 To 256!" could then be, conceptually, an iTunes song.

I'm not worried yet about how to couple the devices. I believe it must be doable using op-amps or optical coupling.

I am worried about the 'frequency'. Could I indeed create 250 kHz signal that would make it all the way to the audio-out? Would the signal 'survive'? (250 kHz signal is based on the 4 micro second width of a bit in the DMX512 signal).

  • 1
    \$\begingroup\$ No you couldn't \$\endgroup\$ Jul 6 '14 at 19:27
  • \$\begingroup\$ There is a DMX shield for Arduino. \$\endgroup\$
    – Matt Young
    Jul 6 '14 at 19:29

Not possible. Your audio card has DACs that run at a maximum sample rate of 48 ksps, possibly up to 192 ksps if you have a really expensive professional card. At 48 ksps, the maximum frequency you can synthesize is 24 kHz.

I suggest looking at this libary: https://pypi.python.org/pypi/dmx/1.0 . It is a python interface to a standard USB to DMX bridge box. And here is a cheap USB to DMX cable that should work with that library: http://dmxking.com/usbdmx.

This may also be a interesting project to look at: http://www.openlighting.org/ . It seems they use a client/sever architecture to connect applications to DMX universes, and it works with a wide variety of USB DMX adapters.

  • \$\begingroup\$ Thanks for quantifying your answer! Also thanks for providing me with links that I couldn't have found myself (and I realy tried) \$\endgroup\$
    – Ideogram
    Jul 6 '14 at 19:52

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.