Question on Controlling Lights

hlbly1969

Member
Hello All,

I run the light show for a 6 piece cover band.

Currently using 3 different hardware controllers to run these lights. However I am switching over to computer control.
Will be using Lightfactory software to control the lights. I want to be able to trigger the lights through Midi notes that come from the drums and Keyboard.

I would like to feed the triggers from the drums into a "brain box" but also run the midi out from the keyboard into the same box and then to the computer. From the box to the computer could either be connected via USB, network or DMX. Prefer network or USB control

I would love to keep this as simple as possible. I already pack in way more stuff than I would like to. But the band has really prospered with the light show that I do for them and I enjoy doing it.

Any advice or suggestions would be greatly appreciated.

Thanks
Bill
 
Lightfactory is good software, especially with the additional hardware controllers to give you a more console like feel. To control the lights from the keyboard you would need a MIDI to USB converter. I can't tell you exactly how to set this up, but it will be relativity simple. You may also want to control them from somewhere other than the side of the stage, you may need a USB or MIDI extender, you can make them yourself using cheap Cat5 cable, using this pinout. I can't tell you what the maximum lenth you can run it is. You can also run it through XLR, the downside is you only get 16 bit signal, but this won't effect you much, again, making them yourself is cheaper than buying them. You can also run your DMX down XLR too, but for long runs it is not advisable, there are plenty of threads about this on here. If you want to risk it, its up to you.

You would also need a USB to DMX converter, but I presume you know that.

Nick
 
Thanks Nick for the input.

I usually run the lights from out front. I use at least 1 moving head and will add to this over time. Its much easier to see where to point it from out front than it is from the side ;)

The Cat5 cable is a good trick that I wasnt aware that could be done. This will make it easier to run from the keyboard out to the computer.

Does anyone know if there is a box that I can run 2 inputs to and have one output from? I would like to run the output from the drums to a midi box and the output from the keyboard to the same midi box. then the output from the midi box to the computer with the correct midi notes from each.

Thanks
Bill
 
...You may also want to control them from somewhere other than the side of the stage, you may need a USB or MIDI extender, you can make them yourself using cheap Cat5 cable, using this pinout. I can't tell you what the maximum length you can run it is. You can also run it through XLR, the downside is you only get 16 bit signal, but this won't effect you much, again, making them yourself is cheaper than buying them. ...

From http://www.richmondsounddesign.com/faq.html:
MIDI Cable Length Q: I know the MIDI specification says there is a maximum cable length of 50 feet (15m) but how far will it really go?
A: The only perfectly correct answer to this is to try it with the specific equipment and cable you want to use dressed where you want it to be and see if it works.
Here are the facts:

  • Most MIDI equipment manufacturers have copied the examples (which are pretty good designs) from the original MIDI specification provided by the MIDI Manufacturers Association (MMA) for their MIDI IN and OUT circuits. There is no guarantee they have designed these circuits as well as they can, but most designs are good if not better than the MMA example circuits.
  • The MIDI specification (especially if implemented using the example circuits and even more so if designed as well as possible) is inherently well conceived for transmission over long distances using typical cabling. The reasons for this are:
    • The receiver is differential and optically isolated. It also has a back-EMF diode (if the equipment truly obeys the specification)
    • The transmitter is fully balanced as long as it has been correctly designed. Early circuits used TTL logic with an open collector driver which does not work as well as current glue logic technology but that technology has essentially been obsolete for 15 years.
    • Low voltages (5V maximum) and reasonably slow bit rates (31.25kHz) are used
    • Digital data is transmitted via a current loop transfer function (rather than voltage level detection) and this is an inherently more robust protocol since noise sources are extremely unlikely to induce enough current (especially considering the very low impedance nature of the receiver circuit) to create errors
The process of MIDI transmission is very similar (despite significant differences) to the transmission process that modems employ - a process which normally works quite well over many kilometres of small gauge unshielded telephone line pairs.
A major difference between the two lies in the fact that modems use very powerful error detection and correction algorithms which normally prevent incorrect data from being received.
MIDI does not have any such error detection capabilities.
Some MIDI standards (such as Two-Phase Commit Show Control commands and File Transfer Protocols) have fail-safe error detection/correction built in but this is not generally true.
If any device could become dangerous if incorrect data were received, then a robust MIDI link must be used.
The most robust MIDI link we know of is our NetMIDI E-Show device which carries MIDI over a network.
Most other devices we have investigated which purport to be a 'long distance MIDI transmission link' actually use a variation of the EIA RS-422 standard which has a very long but definitely finite range.
We are also not aware of any such device which includes error detection/correction capabilities.
Because of this and since RS-422 uses voltage level detection and it is technically more susceptible to induced noise errors than the current loop design of MIDI itself, we do not recommend such units.
In fact, we know of nothing which is in fact more robust than simply using well designed MIDI equipment and interconnect cabling which follows standard procedures for data transmission integrity.
For those more familiar with audio than data, follow the procedures you would use with audio lines.
Specifically:

  • Keep total loop impedances to a minimum within practical cost limits. The inherent impedance of a MIDI receiver is minimum 200 ohms so the total loop impedance should not exceed 20% of this value or 40 ohms
  • Keep cables away from power lines or other wiring carrying high voltages, currents or especially noisy transmission cables
  • Use twisted pair instead of untwisted pair and shielded rather than unshielded cable for maximum noise rejection - although these are definitely not essential and many installations use basic telephone wiring quite successfully over long distances
  • Use good quality locking connectors in non-corrosive and non- condensing environments
Adhering to the above guidelines will result in the most reliable connection and the longer the run, the more important they become.
We have seen many installations in which some or all of the above have not been followed and MIDI was flawlessly transmitted, so designing a successful installation involves many intangibles which may or may not affect the ultimate result.
Which is how we get back to the original and only genuine answer:
Try it with the specific equipment and cable you want to use dressed where you want it to be and see if it works.
One final caveat: if you want to use a 'MIDI powered' device such as the type made by MIDI Solutions, you will have to use a third conductor to carry ground/earth from pin 2 of the MIDI OUT or THRU jack to the device even though ground/earth is not required according to the official MIDI specification. If you only utilize a signal pair to carry MIDI in your installation, then you may have to add a MIDI Solutions Power Adapter at the receiving end of your connection to provide local power for 'MIDI powered' devices, but this is a very good solution to this problem.
The MIDI Solutions Power Adapter will probably extend the distance MIDI can be carried over standard cables. Connect one to the MIDI OUT of the sending unit and another one to the MIDI IN of the receiving unit. If this does not extend the distance far enough, connect more at evenly spaced intervals through the length of the run.
For Show Control applications, the JLCooper MLA series of MIDI Line Amplifiers is often used when sending MIDI signals over long distances.

...Does anyone know if there is a box that I can run 2 inputs to and have one output from? I would like to run the output from the drums to a midi box and the output from the keyboard to the same midi box. then the output from the midi box to the computer with the correct midi notes from each.
MIDI Solutions™ Merger appears to fulfill your requirements.
proxy.php

I'm sure there are others, just Google "MIDI mergers."
 
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