Trying to understand Universes

Looking for help understanding setting up Universes.

Ok I'm a volunteer at our PAC which is a new high school(fall 2018) with 860 seating. We have 15 Pars above stage, CYC lights, 6 Mythos plus a number of Lekos on all 3 electrics & FOH. I understand how to patch into the different universes for each fixture. Plus we are currently patched into using 2 universes. But I am trying to understand what I think is the hardware side. our 1st & 2nd Electrics & the FOH(Catwalk) are on the 1st universe. The 3rd Electric & the 2 Mythos on the Catwalk((Data fed is via a wireless setup to the CAT) are on the 2nd Universe. Is each universe set up at the DMX Control unit & either hardwired in to the Electrics or Wireless sent? How would I go about adding a 3rd universe if we wish to do this so we can have more options with the total number of addresses we can use? Looking to educate myself on this topic so any help is awesome. 

  • Jeff,

    The exact answer will depend if you are using a network or the DMX directly out of the console and what type of console you are using but the basics are:

    - 1 Universe contains 512 channels that are used to talk to your devices.

    - Devices can use 1 or more of these channels to control each function the devices offers (ex Dimmer uses 1, RGB LED Par uses 3, Mythos uses up to 34)

    - If you are using the ports on your console for DMX, each one of these can be assigned to different universes or the same depending on how you need to distribute the 512 channels of control within each Universe.

    - If Port 1 & 2 are Universe 1 with 3 & 4 on Universe 2, this will give you 2 physical DMX ports for each universe and allow you to split your 512 channels for each universe over 2 separate daisy chains worth of fixtures (for a total of 1024 total control channels over 4 runs of cable).

    - In your example, you have added wireless to help with the distribution of DMX.  Continue to think of wireless as a DMX cable out of your console or the next device in a daisy chain from a fixture.  The same Universe and Channel count  limitation is continued on the wireless as if there was a physical cable between.  Nothing else changes.

    - ETC EOS consoles don't care about how many Universes you use and are only limited to the number of Outputs (DMX addressed) being used for output from the console.  For simplicity, if your consoles output limit was 100 you could have 10 devices each using 10 channels all on Universe 1 or you could split these devices over multiple universes to make patching and cabling easier.  (Other consoles may limit you to only using Universes 1 to X so please refer to their limitations.  For example the ColorSource console limits you to Universe 1 on port 1 and Universe 2 on port 2)

    - Remember, a Universe of 512 channels is only the maximum channel count you can have.  You can use as many or as few of these channels as you'd like before starting another universe.  Some people like to fill a universe until they can't add any more fixtures before adding another while others like to keep a truss/pipe or section of the stage on it's own universe for easier troubleshooting (ex FOH pipe on Universe 1, Stage pipe on Universe 2 and Floor Package on Universe 3)

    - If you'd like to use another Universe for more devices, this will depend if your console had open DMX ports on the back that you can assign this new Universe to (assuming this is the configuration you are using).  If you are using a network from your console, there will be DMX output devices (Nodes) in the venue that have these DMX ports and are configured to output each universe.  You may have to purchase a DMX opto-splitter that will allow you to free up a port on your console (if more than 1 is outputting the same universe) or another network Node to assign this new universe for more efficient use of your consoles output capacity.

    I hope this helps and I'm sure others will chime in with better ways of explaining the concept.

  • There is a tall control unit that is stage left that controls DMX. So I think we run on a network. I will verify later today what the unit is.

    Correct me if I'm wrong a universe is like a road that the traffic lights are daisy chained on so to be controlled by only addresses patched to that road/universe 1. if I try to add a light that is patched to universe 2 channels it would not be able to work on this road because its universe 1. I would need to re-patch it into the channels still remaining on universe 1 for it to function.

    On a network how are the data cables/wireless devises assigned universes?

  • I also need to see where the CAT mythos are getting there wireless signal from which is attached to universe 2 somehow. I'm thinking it could be anywhere in the daisy chain along the data cable of universe 2 & work or it could be located near the control unit stage left. 

  • just another attempt at explaning. sometimes it helps if multiple people try explaining the same thing in different ways.

    in the "old" days (5pin XLR aka "DMX" connectors) you had one DMX cable. it could transport 512 pieces of information. at some point a 2nd and 3rd and maybe even a 4th cable were added. later, instead of adding more individual cables the idea was to just run one Ethernet (= "network") cable and feed the various data streams that used to run in seperate cables into the same network cable. and now suddenly we needed to be able to distinguish between the pieces of information that used to run in the first cable and those that ran in the second cable. because data now suddenly could "mix", it wasn't isolated by cable insulation from each other anymore.
    that's where the universes come in. a universe hold 512 addresses, aka exactly what we used to be able to run in a dedicated DMX cable. so think of Universe 1 as a virtual DMX cable.

    so nowadays (especially in a newer install like yours) you would have aconsole that generates lots of information and feeds those into the network. looking at it from the receiver side, the fixtures usually don't have network ports (but that's becoming more common), they are expecting old fashioned DMX. so now we need a way to get the DMX out of the network. that's where Gateways (sometimes called nodes) come into play. they get fed the information from the network, then sort the information by universe number and finally output this to a DMX socket.
    which universe they're outputting to which of their DMX sockets is configurable.

    the DMX communication is one way (this is a simplification, there are feedback capabilities, but let's keep it simple for now). the console feeds all the information it has into the network and then you have the gateways that listen for data that's marked with the universe number it's supposed to be listening for.
    if a gateway has multiple outputs it can listen to a different universe for each output, or it can output the same universe to multiple of its outputs. and also multiple gateways can be listening to the same universe if they want to.

  • Jeff,

    You are on the right path.  Each Universe it's own highway of control from your console.  A light gets assigned a DMX address and then get's placed on one of these highways though a hardware output and cabling.  A fixture does not get assigned a universe.  A set of conference rooms is another great example.  A fixture can only be in one conference room at a time and waits for someone to start talking to them and cannot listen to anyone on the other side of the wall (the other universes).  If you need to add more people to the party and the other conference rooms are full, you open a new conference room (universe) and add or move people into here.  The walls and capacity limits still exist but we don't care who is in each room as long as the console can still talk to all the rooms.

    There should be a wireless transmitter somewhere along the line that is sending these fixtures data.  Also, I'm going to assume your "tall control unit" is either a dimmer or equipment rack.  If it's an equipment rack, there will be multiple devices inside that could be handling your distribution.

  • Thanks for explaining this. I will be at the PAC later & will be looking for clues to the setup. So I will most likely follow up with some more details & questions.

  • This is great info. I'm understanding a good chuck of it already & I'm sure the rest will make since in time. 

  • What do you see in these pictures?

    Am I right that there is a network?

     Control tower system

    Ethernet cables (2) are blue on main line to 3rd Electric.

    Ethernet to DMX

    So in general what would have to happen to add a 3rd universe to the system?

  • Jeff,

    You are 100% correct.  You have a network install.  The device installed in your raceway labeled “Universe 2” is a one-port gateway which converts the network DMX traffic (SACN) into standard 5pin DMX.  This device is configured to only output information for Universe 2 and you would have another one somewhere distributing Universe 1.  In order to add another Universe to this system, you would need another 1 port gateway.  Conveniently if you are looking to add it to this same location someone has designed the system with a spare Ethernet port that you could use.  Essentially the new gateways needs to be plugged into one of those ports on your switch configured for VLAN 11 (Lighting) so make sure this port is patched correctly.  I’ve included the link again for ETC’s selection of gateways.  I recommend the 1 or 2 port portable gateways as they can be rehung anywhere you need them.