5, 12, 24 volt system?

[sittinguphigh]

Does the volts in the line have a effect of the node?
Does the volts in the line enable you to go longer with the string?
I know people in this site have take the 12 volt system to 8 volts.  Does this change the brightness?
Is the node volt draw the same?

[caretaker]

LED themselves have a (forward) voltage of 2.2 (or so) for RED and 3.2 (or so) for Blue/Green. So any voltage over that requires resistors to safely drop the voltage to what the LED can handle. So why not just use 3.2 volts for nodes? Simply the greater the voltage the less the amperage used (it's a Ohms' law thing) So by increasing the voltage to 12 volts you need a lot less amperage for say 128 nodes. That is why RJ designed his system using 12 volts because it allows 128 pixel string nodes to be run on a CAT5/6 cable without exceeding the amperage limit of the cable. Basically it comes down to what resistors are in the node as to what voltage it will run at. Personally I would recommend staying with 12 volts smart strings and more specifically with the that have been tested and to work with RJ's equipment design as you will have a lot less headaches.

[tbone321]

There is a big difference between smart string nodes and dumb strings.  Since you said nodes, I will assume that you are talking about smart strings and with them, the simple answer is that the nodes need to run at the voltage that they are designed for.  Running them at a voltage over the rated voltage can toast the control chips in the nodes and running them at too low of a voltage can cause the nodes to become eratic, just shut down, or freeze.  The reason for using the higher voltage nodes is to reduce the effects of voltage drop which does allow you to run longer strings without the need for power injection but as said before, if it is a 12V string, then it needs to run at 12V.  Applying 24V to a 12V string would toast the entire string.  Lowering the voltage should not have much effect on the brightness of a smart string node unless you really get the voltage low and then you have a better chance of the string screwing up. 

[sittinguphigh]

So trial and error on how low you can go.

[taybrynn]

Stay with known / proven designs as caretaker said .... or prepare for the $$$$$ bleeding edge $$$$$ ....  But why?

[caretaker]

So trial and error on how low you can go.

Yes you can drop the voltage somewhat, but it will reduce brightness and may also cause data corruption problems depending on how many pixels are in the string. Again stepping out from the ratings for the device is asking for trouble.