Customer Question: Should I use a centralized or de-centralized controller for an element?

HolidayCoro sales/support often sees common, open-ended questions from our customers and here on our blog we post detailed responses publicly so that other people will be able to learn from the decision making process we use to answer these questions.

Today's question is:  "I am making 16 pyramids and would like to light them up using 3 or 4 Basic Rectangle RGB LED Waterproof Module per pyramid.  The pyramids will be in the front yard each about a yard apart.  My Question - should I buy 16x Item #30 Basic 3 Channel RGB DMX Controller or should I buy 2x Item #24 Basic RGB 27 Channel DMX Controller.  Is there any advantage to either in this situation?"

For this given project it has already been determined that basic or dumb RGB lights should be used as opposed to pixels and this is often the case when an element doesn't need the control that pixels offer or when there are larger distances between elements.  So the question becomes - should the basic RGB DMX controller be centralized in the form of a 27 channel (9 RGB outputs) DMX controller or individual 3 channel (1 RGB output) DMX controller in each element?  The issue comes down mainly to two factors - cost and complexity:

• Cost - The number of RGB lights won't change between the two methods, so we'll exclude that from the calculations, though what does mainly matter are wiring, power supplies, controllers.  Also, we need to determine he power consumption of the RGB Modules, which in this case consume about 100ma (1/10th of an amp) at 12v DC - or 16 elements x 4 modules is 6.4 amps total.  So, we'll take the number of individual elements here - 16 and do some comparison math with the two options: 
• Centralized - This method allows us to have one (or two in this case) centralized controllers - the costs involved are:
• $114 ($57 x 2) - 27 Channel DMX controllers
• $26 ($13 x 2) - 45w (3.75amps at 12v) power supply.  This solution would power each 27 channel controller with a single power supply.  It's a little tight on the power at 3.2 amps total per controller (32 modules per controller) but it should work.
• $20 ($10 x 2) - Waterproof housing.  The 27 channel controller isn't waterproof, so you'll need a waterproof/resistant housing and this varies by region, water/snow conditions and budget.
• $20 (100ft @ $.10 per foot x 2) - CAT5 wiring.  You'll need to get the output of the controller out to the individual elements and CAT5 would be a good solution here as the current consumption of the lights is below the current carying ability of CAT5 at a bout 3 to 4 amps and it has 8 wires, so you could double up each wire for the 4 wires required for RGB lights.
• ~$180 - Total
• De-Centralized - This method allows us to have an individual, 3 channel DMX controllers in each element - the costs involved are:
• $144 ($9 x 16) - 3 Channel, CAT5 based controllers
• $26 ($13 x 2) - 45w (3.75amps at 12v) power supply.
• $8 (80ft @ $.10 per foot) - CAT5 wiring.  Using the DMX+Power over CAT5 system, it is possible to inject power at the start of the string and again at the 8th element.
• $23 ($1.50 x 16) - 3 Way Splitters for the DMX signal+power.
• ~$201 - Total

Of course there are other minor costs - shrink wrap, solder, tools, shipping, etc and we've not included those in the calculations above.  So, on the surface, they look pretty much about the same from a cost basis, so let's take a closer look and consider all the other factors:

• Complexity
• Interconnections - Left out from above on both are how you'll interconnect the wiring from the element to the controllers.  
• Centralized - With the centralized solution, you could solder the CAT5 wire directly to the lights in the element and then have elements with 20, 15, 10 and 5 ft lengths of cable coming off them and then you'd fish that wire into the controller case and screw it down to the terminals on the controller.  The problems with this solution are that it makes future adjustments in length complicated since you've already set the length of the cable from the element to the controller when you built the element.  Additionally, you'll have to deal with elements that have attached wire and then manually wire up each element to the controller, adding to your display setup time.  An additional down side to this method is that you also have more wire spread out over your display which can present safety/tripping hazards.  The upside to this method is that it doesn't really require any additional connectors - just tin the wires where they go into the controller screw terminals.
• De-Centralized - If you've placed the individual CAT5 controllers in each element, that means that you can simply attach a 3 way splitter to each CAT5 plug, then plug in the necessary CAT5 cable between each element (5ft lengths in this case) in a daisy chain arrangement.  Then you just build a power injector for each of the two bands of 8 elements and this allows you to run the power and the DMX signal from one element to the next.  The amount of wire is limited as it only goes from one element to the next.  The down side is that you need to ensure that you control water ingress in to the CAT5 connectors and use a corrosion control spray - usually mounting the controller up-side down under the element would be more than sufficient to manage water ingress.  The real beauty of the Power+DMX over CAT system is that you can assembly your display quickly just by plugging into each element to the element next to it.

Factors to Consider When Designing an RGB Pixel Matrix

Over the years we at HolidayCoro have been asked why we only sell a single pixel matrix product - our 18" x 24" pixel with either 150 or 162 pixels.  Well, actually, we've produced a fair number of custom matrix based panel items for customers over the years and the main reason we don't offer all these variations for sale is because each project is so different.  The article hopes to provide information on factors that we consider when working with customers on designing a pixel matrix and hopefully this will help those building their own or working with us to custom produce one.

• What exactly is the purpose of the pixel matrix?
• Is this matrix intended to be dense enough that viewers will be able to see objects scrolling or displayed on it such as text, icons or logos?  
• What is the viewing distance from the matrix to the viewer?  If you've ever looked at a big screen TV up close, you can understand the relationship the size of the pixels (lights) have to the distance they are being viewed from.
• What is the viewing angle?  A curve pixel panel (such as a pixel megatree) can look odd if all the pixels in the matrix are not visible to the viewer.
• What is the shape of the matrix?  Is the matrix a cone, in the case of a pixel megatree, where the pixels at the top are in a much higher density than those at the bottom of the tree?  Is the matrix cylindrical?  flat? concave or convex?  All these designs have an effect on the final output, pixel density and mounting methods.
• Technical factors to consider include:
• Number of pixels - This is an important factor to consider and the number shouldn't be random - it should be based on the design requirements.  Look closely at how many pixels you'll need and their spacing from each other.  If needed, build a sample mock-up and view it from the distance and angle you expect your viewer to view it from. 
• Pixel height and width - Also consider how many pixels you may need to display certain items such as a text font which often require a 5x8 pattern.  Again, keep in mind that you will also need to have the pixels close enough that the human eye can make out the pattern - just because it might look good in the sequencing software doesn't mean that will translate into the real world.  
• Multi-Panel Alignment - If the matrix will be comprised of several panels, be sure to carefully consider the spacing within a panel and how it relates to the spacing induced between two adjoining panels.  This may mean that you will need to increase the center-to-center spacing of the lights to match that of the panel-to-panel gap.
• Mounting or support - An important part of any matrix is how you will mount it - because a matrix tends to be a flat area (excluding pixel megatrees), you'll need to think hard about what system you'll use to mount the substrate on to which the pixels are mounted. If that surface catches the air, there could be problems with it blowing over or toppling the support structure.  Also consider that you'll need to store this mounting system in the off-season - so if the panels need to go into an attic, consider the opening going to the attic.
• Substrate mounting - In most cases, you'll need to mount your pixels to a substrate - not only to support them but to maintain a clean and even spacing - there isn't anything worse than a matrix that has mis-aligned pixels.  How you mount those pixels can vary - it could be holes in coro like we do at HolidayCoro or it could be screwed or glued to wood slats or plywood - this all depends on your pixel type.
• Pixel type - The type of pixel you select will often be a by-product of the distance and viewing angle of the people viewing your matrix.  These pixels could be in a strip form, node form or module form and each has it's pros and cons and there is no one pixel that is best suited for all matrix types.
• Channels - Keep in mind that you'll often have many, many DMX channels on a matrix display and it makes sense to select pixel counts that fall within a set number of DMX universes - so don't design a pixel display that requires 180 pixels (18 wide by 10 high) if it could have been done in 163 pixels (18 wide by 9 high) which fits neatly into a single DMX universe and thus saves you a controller or controller output and also makes your sequencing easier to setup and manage.
• Repairs - Factor in that pixels DO fail and that you'll need to fix them.  So consider how easy it will be to remove and replace pixels.
• Cost / Budget - A matrix can grow in cost quite quickly when you factor in hundreds to thousands of pixels, so be sure to ask yourself the overall value of the matrix and how well it accomplishes its goal.  If this is just for announcing the radio station and song titles, a simple matrix will do - if you need to scroll logos or animations, you'll need a larger and more expensive matrix.
• Big isn't always better - Since pixels have come down in price and complexity, we've seen a number of pixel matrix panels (and pixel megatrees) in displays that just completely over-shadow and "hog" the display.  We believe that a well balanced display should be the ideal and that one mega-element can leave your audience so fixated on one area that they fail to see other areas and animation. 
• Software & Sequencing - Building a matrix panel is only one part of the process and the other major part is generating the sequencing for that panel.  Since it is nearly impossible to "hand" sequence matrix displays, you'll want to consider xLights, which has matrix effects, scrolling text, pictures and video built in.  You may even want to design your pixel display hardware, then start sequencing it before you buy or build it to evaluate how complex it will be to sequence the matrix. 

Customer Question: How many lights can be hooked up to the TinyPix?

Legacy technology notice (updated September 2026): This post covers the TinyPix, an RS-485 DMX pixel controller we no longer sell. That is now considered ancient technology. All modern lighting control, including every pixel controller we sell, runs over Ethernet using E1.31.

If you are building or expanding a display today, start with our guide, Where Do I Start When Designing a New RGB Pixel Project. About 80% of our residential customers sequence with xLights, which is free and works with all of our controllers. We have left the original post below for anyone still running legacy hardware.

HolidayCoro sales/support often sees common, open-ended questions from our customers and here on our blog we post detailed responses publicly so that other people will be able to learn from the decision making process we use to answer these questions.

Today's question is:  "I see that the smart pixels 8mm come in a max of 100 per string, however a TinyPix can control up to 170 pix. So if I wanted to control 150 8mm smart pixels, can I do that with one TinyPix? If so, how would the 2 strings (100 & 50) be hooked up to the TinyPix, and what kind of power supply would be required? (I assume the 45w one would be too small for 150 8mm Smart Pxels)."

I can see that the customer understands that the TinyPix controller can handle 170 pixels (510 DMX channels (170 * 3) or almost a full DMX universe that is 512 DMX channels) as that is covered in our documentation on the product page.  I can also see that the customer is aware from the product page for the 8mm smart pixel nodes that the pixels come shipped in 100 count maximum per string.  So, we have several issues here, some of which we have information on and some we don't.

Design - There isn't any design information provided, so we don't know if these are being used in a concentrated matrix or string over a long distance, such as a pixel tree or a soffit on a house.  Why this matters is because if the pixel nodes are all close together, it can be fairly easy to inject power (more on that in a minute) as where if they are in a long single string over a distance, it can be harder/more complex to inject power.  Additionally, we don't know if this is for a single element or many elements and the distances of those elements.  We would be generally suspicious if the TinyPix is even the correct item for this design because we suspect that it would be one of several units where a centralized pixel controller would be a better match.

Signal - A TinyPix controller is a RS-485 based controller and thus needs a DMX source, such as our Actidongle.  A single Actidongle could output 512 channels, so it could handle the 150 pixels (450 DMX channels) without issue - IF - the customer only has one of these items with such a high channel count.  If the customer has several other 150 pixel elements, they would need more DMX dongles and at some point it is likely cheaper to invest into a centralized pixel controller with a E1.31 inface.  Again, since we don't know anything about the overall design the customer has in mind, we can't recommend a specific solution here or if the TinyPix is even the right item for this customer.

Power - An important part of any RGB design is power management - we've covered this in many articles and knowledge base articles.  So, given that we know we are going to have problems if we try hooking more than 150 pixels together end-to-end from a power loss standpoint, we recommend the customer review our blog post about how to manage power injection and power supply selection (because the customer had also asked if the 45w power supply was sufficient to power them.)

So, to recap - yes, the pixels can be connected end-to-end in an amount UP TO 170 but just because that can technically be done by soldering the wires together to make a single length, doesn't mean they will work without managing the power issues.  The issue at hand is that there will be just too much power drop over the pixel wiring and thus power injection would need to take place, likely at the start (through the controller power outputs) and again at the end of the string.  This is what we recommend with our 163 and 150 pixel scrolling RGB matrix signs since it is easy to put power in at both ends of the wire, thus resolving the power drop issues since everything is close together.  If the pixels were used on, say, the front of a house or to outline windows, you'd need to still carry the power to the end or middle of the string for power injection.

The second part of the customer's question if our 45 watt power supply will be able to power all 150 nodes.  So, first we need to look at the overall power consumption of the nodes, which is:  White (all three colors) 100 Nodes: 3.6 amps / ~44 Watts  We can see right away that at 44 Watts for 100, that a 45 Watt power supply isn't going to cut it since 44 (100 nodes) + 22 (50 nodes) would be 66 Watts total, plus add in another few Watts for line losses and a safety factor and we are up towards about 75-80 Watts to be safe.  This excludes looking at any other factors such as additional controllers, etc - hence, why it is good to know the overall design involved.  So, normally I would just recommend hooking up a 250 to 350 Watt power supply.  They are not that expensive and likely the customer also has other controllers that could also piggy-back off this same power supply.

So, in conclusion - the customer would best benefit by providing as much detail as possible about the overall scope of the project and where this specific element fits into that project.  We understand that often customer just want a simple answer to their question and do not yet understand the underlying complexities that comprise an important part of the decision making process.  In this case, it would be helpful if the customer were to review and then understand the power and DMX addressing issues under-lying the technology in the TinyPix (and all DMX controllers.)  While this process can be long and tedious - taking weeks or months for some customers, this knowledge is a fundamental requirement for customers selecting a completely DIY solution, as we talked about in our DIY vs Commercial solutions blog post.

How many lights can be connected to a controller, what controller do I need for RGB lights, what wiring should I use for RGB lights and/or what power supply do I need for my RGB lights? (Updated for 2026)

Updated September 2026. This post was rewritten around pixels, which have replaced dumb RGB for nearly every holiday project.

We often get asked how many lights can be connected to a controller, what power supply to use and what wire to run. This post answers those questions for pixel lights and pixel controllers.

A word of caution first: if you get the power side wrong, the results range from flickering lights to damaged hardware and, in the worst case, a fire. Don't "wing it." If you'd rather just have the answer, fill out our project design form and we'll put together a recommendation and a complete quote, or start with one of our Ready2Run packages, where the power math is already done.

The key is to see the lights and the controller as parts of one system:

Pixels → Pixel wiring → Controller → Power wiring → Power supply

Let's work through the chain.

1. The pixels

Everything starts with the lights, because every other part is sized to them. When choosing pixels, consider:

• Format. Nodes, strip, modules or bulbs, depending on how you'll mount them and whether they need to follow corners or curves. For house outlines, MegaTrees and props, 12mm nodes are the most common choice.
• Voltage. Pixels are usually 5v or 12v DC. 12v runs farther before you need to inject power and is the more forgiving choice for most holiday projects. 5v is slightly more efficient but needs more careful power planning.
• Power draw. This is the number that drives everything else. Our 12v 12mm nodes draw about 45 milliamps each at full white, or about 0.55 watts per pixel.

Always figure power at full white (red, green and blue all on), since that's the most a pixel can draw.

2. The pixel wiring

This is the wire between each pixel in a string, or the circuit board in a strip. It carries power from the controller down the run, and it's where most power problems start.

There's no standard here. One vendor's nodes may use thick 18 AWG wire while another's look identical but use thin 22 AWG. Thinner wire loses more power over distance, so the pixels at the end of the run get less voltage than the ones at the start.

Ideally, your vendor tells you how many pixels can run before you need to inject power. Our 100-count 12mm node strings, for example, are designed to run the full 100 nodes with power fed at the start. If your vendor doesn't publish this, measure it yourself: set the run to full white for 15 to 30 minutes, then measure the voltage at the first and last pixel with a meter. A drop of 10 to 20% is usually fine. Much more than that and you'll see dimming, color shift or random flicker at the end of the run.

When a run is longer than the pixels can carry power, you inject power: run heavier wire from the power supply to a point partway down the run and connect it to the string's power and ground there. The data passes straight through.

3. The controller

A pixel controller receives data from your sequencing software over your network (E1.31) and sends it to each pixel. It also passes power from the power supply through to each output. When sizing a controller, check:

• Pixels per output. How many pixels each output can drive. This is usually the limit you hit first on long runs.
• Current per output. How many amps each output can supply. Divide your run's watts by the voltage to get amps: a 100-pixel run at 0.55 watts each is 55 watts, or about 4.6 amps at 12v.
• Current per bank and per controller. Larger controllers split their outputs into power banks, often each fed by its own power supply.

Don't size by the fuse. The fuse is there to protect against a short, not to tell you how much the output can carry.

Our Controller Selection Wizard will match a controller to your pixel count and power, or see our Ready2Run pixel controllers.

4. The power wiring

This wire carries power from the power supply to the controller, and to any power injection points. Size it by two things: the total power of every pixel it feeds, and the distance it has to run. Two controller outputs of 55 watts each need a wire that can carry 110 watts over that distance. Our technical guide to wire selection has the charts.

5. The power supply

The power supply is the last thing you choose, and it's simple once the rest is done:

• Total power. Add up every pixel it feeds at full white, then add 10 to 20% headroom. 576 pixels at 0.55 watts is about 317 watts, so you'd want a supply rated comfortably above that.
• Voltage. Match your pixels: 12v pixels need a 12v supply.
• Enclosure and cooling. Outdoor supplies need to be protected from water but still get enough airflow, since larger supplies often have fans. Our Ready2Run controllers come with the power supply already mounted in the enclosure with the controller.

See our power supplies.

Putting it together

Work from the pixels up: count your pixels, figure watts at full white, split long runs or plan power injection, pick a controller with enough outputs and capacity, size the wire and pick a supply with headroom. For a complete worked example on a real house, see our detailed house outline design guide.

Related posts:

• See the effects of power draw on long runs of pixels
• Where do I start when designing a new pixel project?
• Dumb RGB or pixels: which is right for me?

HolidayCoro.com

How To Question: Pixel Arches

Legacy technology notice (updated September 2026): This post covers the TinyPix, an RS-485 DMX pixel controller we no longer sell, along with LOR S3 and serial DMX dongles. That is now considered ancient technology. All modern lighting control, including every pixel controller we sell, runs over Ethernet using E1.31.

If you are building or expanding a display today, start with our guide, Where Do I Start When Designing a New RGB Pixel Project. About 80% of our residential customers sequence with xLights, which is free and works with all of our controllers. We have left the original post below for anyone still running legacy hardware.

Today's question comes from Phill who asks:

After reading, and watching several videos on your site, I would like to test an RGB Pixel setup (100 lights per string, using your tinypix controllers). I am using LOR S3 Advanced software, and would like you to verify what I will need (to make sure I don't miss anything).

Currently, I am just using the inexpensive Light-o-Rama USB485 dongle, at 500K (network speed), and it works great - will that work, or do I need to use one of your dongles, and if so which one - Ultimately, I will be using this for 12 arches (50 pixels each).

I know I need a 100 light pixel string, 1-tinypix, programming cable, and power supply - for the testing of the single string, I will just use one I have on hand). other then the possible dongle, is there anything else I will need???

 

So let's break down this issue - Phill would like to make pixel arches and he has indicated that he needs 12 of them at 50 pixels each.  My first question would be - what type of RGB pixel is being used here?  My guess is pixel strip given that the number is 50 pixels and pixel strip commonly comes in 16' lengths that contain 50 pixels (150 DMX channels), so we'll go with that given that pixel strip is a reasonable choice for pixel arches.

 

The next question I'd have is - what type of interface is going to be used here to get the sequencing data to the pixel controller?  50 pixels * 3 DMX channels (Red, Green, Blue) * 12  = 1,800 DMX channels - so that's a fair number of pixels and is comprised of 3 DMX universes (actually 4 because you would likely put 3 arches of 150 pixels each, within a single DMX universe of 512 channels.)  So, I think an RS-485 interface is out of the question here - the customer is going to need to go E1.31 for output of that much data.

 

So, to answer Phills question about LOR - yes, you'd need at a minimum LOR S3 advanced to get enough output and E1.31 support.  Phill would run the LOR network separately of the DMX network, so Phill's LOR settings really don't matter here since they don't impact the DMX E1.31 network.

 

Phill mentions needing a "100 light pixel string" which isn't correct based on my assessment that he has chosen RGB pixel strip, so maybe he is referring to 8mm pixel nodes?  If that is the case, usually 8mm pixel nodes would be a bad choice for this design - they don't mount well, you have to get them pointed in the right direction and they have less light output than the 5050 RGB chips in RGB strip - so we are going to just forget the 100 light pixel string reference and again assume he needs RGB pixel strip.

 

Phill also mentions needing a TinyPix -  I can't say if that is the case because I know nothing about the distances involved.  A centralized controller is great, something like the SanDevices E68x or the J1Sys controllers but they do have limits on distances you can place elements from the controller - yea, you can use null/ghost pixels to span longer distances but I'm not sure if we are talking 2 acres or a 5,000 sq/ft yard.  In the 2 acre, now a distributed pixel controller like the TinyPix really makes sense, if you have them all very close to each other, a centralized controller makes sense.  Now please note that the TinyPix is RS-485 based and thus would require "dongles" for output of each DMX universe as where the centralized controllers would require an Ethernet feed from the show computer.

 

So, to completely answer a question such as those posed by Phill, we need to know other relevant data such as:

• The physical design and layout of the display elements (arches)
• Any additional pixels/DMX channels used in the display
• The method the user will choose to sequence the display (software)
• The budget range for this project
• The skill level of the customer (plug-n-play or DIY)

 

Locating and Repairing Bad Pixels

If you have pixels - be they nodes, modules or strip - at some point you are going to have a failure.  That failure could be when you purchase them or over a period of time due to physical damage or other causes.  So, you'll need to have the ability to locate and then replace the bad pixel.  This video shows how to perform this process on nodes (8mm / 12mm) but it also is the exact same process if you have any other type of pixel. 

As mentioned in the video, if you do pixels, you'll need to solder and it's not nearly as complex as you might expect.  Check YouTube for videos on how to solder.

A Demonstration of the Effects of Power Draw on Long Lengths of RGB Lights

Todays blog post is about the effects that power draw has on RGB lights.  We've taked about it before in our blog post about how wiring affects power distribution and in our demonstration example house where we lined it with pixels and handled the issue of power consumption.

This video is pretty simple - it shows 160 pixels (480 DMX channels) connected to a single power supply and our HolidayCoro pixel controller.  It is intended to show the effects that the gauge of the power wire and the power consumption of the pixels themselves have on the actual light output.


(open in YouTube with High Def for better viewing)

Post any questions below.

Thanks,
David
HolidayCoro.com