5v or 12v - this is a continual hot topic within the Xlights/Lighting community of pixels.
Check the bottom for TLDR plus a video!
Which is better? 5v people will say 5v, and 12v people will say 12v, of course. Which is right? Well - both. Which is cheaper? Well - kind of both.
If you've made it this far and you're all in for 5v or 12v you may have already tuned out or disagreed with me - and that's ok. If you're dedicated to your voltage then this may not be the discussion for you. There are a lot of factors that are both obvious - and not - to consider when comparing these 2 types of pixels.
To get this out of the way - all of the pixels run on 5v. This matters in the discussion because how each works and why each work the way they do - this matters. 12v pixels only require 5v - and they have components on board of each pixel (either regulated or resistor) that drop the incoming voltage to 5v. This will matter later and, hopefully, help make sense in the differences.
Pros and Cons of 5v
Generally speaking - 5v pixels can be had cheaper. Be very careful here and purchase good 5v pixels. My recommendation would be to buy from Wallys lights or if you wish to go the Amazon route (which is what we use) - buy Rextin pixels only. Personal experience includes replacing an entire tree mid show season because cheap pixels were having multiple failures every single day - the epoxy was failing and allowing water in.
A batch of 500 Rextin pixels from Amazon, currently, with shipping is around $130, or $260 for 1,000. That's $0.26 each - shipped. The savings of 5v pixels vs 12v pixels doesn't apply if you buy from Wally's as they're priced the same. I just purchased 2,000 12v pixels from Wallys - and with shipping it came to about $566 before tax - or $0.28 each shipped.
Wally's lights are amazing and have such low failure rates. That said, statistically my Rextins have done better. Here is a link to the Rextins we use:
Rextin 5V pixels on Amazon
When using good pixels - the cost savings on pixels is pretty minor, and buying cheap 5v pixels *could* leave you with a lot of repairs and/or replacing them all.
Power supplies are a tad cheaper as well. That said - those cost savings can get eaten up pretty quickly when you start adding in power balancing / power injection. If you run Wally's lights I've heard their larger gauge wire allows you to run upwards of 150 pixes at 20% brightness before you have noticeable color variations, but since I run Rextin I balance every 50. Something like a tree - this is a lot of extra wire since you need to run the length of the strips. My 14' tree has around 300ft of 18/2 cable in it and I prefer to use the brand 'MaxBrite'. Currently a 500' roll is around $110 from Amazon, or a 100' roll is around $38. Either way, around $100 extra in wire for power balancing. Here's that 100' roll I was talking about on Amazon.
Next - in order to properly fuse this - you will need distribution blocks/boards. I will leave that discussion for another day, but I have a preferred method which is around $15 for 6 ports.
When you run power injection - then you get to use a LOT less ports from a controller. As an example, our 14' tree with 24 strings uses 4 ports on a differential receiver. That means there's 6 strings per port. The F16 it's plugged in to is currently split into 36 ports (F16, one expansion and then using the DMX out as an expansion - which I plan to change to a differential expansion board to add additional ports) and it only takes up 4 ports. That leaves my F16 open for 32 more ports/props that I can connect! Big cost savings in controllers.
So what's all of the down side to 5v?
Well - if you don't properly power balance, colors can be off. This is because as voltage travels through the pixels and the wiring, the voltage drops. Since the pixels need close to 5v to run accurately - it doesn't take long for that 5v to drop. Without power balancing a group of 50 pixels can drop the voltage 1/2 a volt or more by pixel 50. That means by 100-150 pixels, at the end, you'll have around 3-3.5 volts, and the colors won't be accurate. This is why power balancing/injecting is so important with 5v.
Next up - time. It can add a serious amount of time to preparing a prop to add in additional power balancing/injection. It can easily take 3-5x longer to add in the power balancing that it took to originally push the pixels in.
Alright - enough about 5v, let's talk 12v!
What are the pros to 12v? Well - they're 5v pixels that are designed to receive up to ~12v of power, then drop the voltage within the pixels. Thinking of the 5v downsides and dropping 1-2 volts over a couple hundred pixels - well, that's ok. If you have 10v at the end of 250 pixels - they will still run perfectly fine without any additional power added in.
That means HUGE time savings. Simply push your pixels and go. On our 22' tree - I have runs of 115 pixels so, yes, I did solder between pixels 100 and 101, so that added a few minutes per strip, admittedly. That said - it was 'push pixels, solder 3 wires, done'.
Colors tend to be a tad more accurate, especially in longer runs of lights.
Those are the plus sides! (Don't let that fool you - those are huge.... the time saved especially)
The down sides - more expensive. Similar rated power supplies (priced similarly) aren't going to be able to run as many pixels - and they will require more power to run. This is because the pixels are receiving 12v and shedding that excess power in the form of heat (you can physically feel the difference, when running, between 5v and 12v). This means - possibly more power supplies for the same amount of pixels and it will take more energy.
There's also been a lot of chatter (and this is sometimes where you can identify the 5v people vs 12v people) - with people posting about pixel fires - all but 1 that I have seen posted online has been 12v. Most likely this is because it's a higher voltage - and there's a slight increase in manufacturing defect potential since the pixel has added components.
The biggest downside is that 12v can eat up ports. If you go 12v and don't want to power inject/balance - then you will be using a LOT of ports. Our 22' tree, with 32 strings - uses 32 ports on a Kulp K32. One string, one port.
Again - as much as that is a downside for port usage, it's also very simple. Once your tree structure is up - put a string up, plug it into it's port, and done.
Both of these mindsets can have variations between the extremes. As an example I could probably run 16 ports on my 22' 12v tree without issue or power injection and free up 16 ports. I could probably run 24 ports on my 14' 5V tree and get away without power injection.
So - TLDR version....
5v is, kind of, cheaper but takes a lot more work. Takes less ports, allows for port packing - which is great until you have failures. More complicated.
12v is, kind of, more expensive but is so much simpler. Takes a lot of ports, so it could get expensive with controllers. So much simpler.
Here's a video where I discuss both trees if you're less inclined to read.
Whichever voltage you pick - consider checking out our props and tools to help you get your show going!