LED Speaker Stand Help

From Rob on the mailing list, 9 Jul 2026 08:13 UTC

Hi all

I'm creating an LED speaker stand and I think I need some help to not burn my house down.

You can see my prototype here (on the right if that wasn't obvious :D)

I've learned loads from making this first one, including some design changes:
1. I want to move the control screen out of the stand itself into a separate control unit
2. I want to daisy chain the power/ data so the stands are identical - fewer things to do in TinkerCAD
3. I probably didn't do enough research on the electric side of things

I'm a bit terrified of turning it anywhere near full brightness - it's currently hard coded on the ESP-32 to 80% brightness but in its current form this will need to reduce to around 30% when the second stand is added. I don't much like the idea of having it limited to 30%.

The central light bar uses 4 strips of 25 addressable LEDs, and there will be two so that's 200 addressable LEDs - 12amp max draw.

With the ESP-32 and screen added I figured I'd need a 15amp power supply to cover the top current draw possible.

My power supply is 5v, 15amp purchased through the wonders of Amazon.

However, it ends in a barrel jack.

I purchased a female barrel jack connector but I believe it has a max rating of about 5 amps.

I've discovered the MR30 connector type which seems OK to handle much more than the 15amps I need. 3 pins allows me to pass the power and data feed -perfect.

My questions are these:
*1. Do I need to replace the barrel jack connection on my power supply?*

Even if the barrel jack that came on it is fine I can't find a female connector that is rated for the power than will be coming through.

How long would I need to leave the power supply disconnected before chopping the old jack off and popping a new connection on? Assuming it will be fine after a few minutes

*2. Does it matter where the male/female connections go?*

I realised I used two male connection types on my base stand for daisy chaining - right for power/data in, left for power/data out to the other stand.

I think the one on the right will be fine as there's no power on these pins ever but if the one on the left has pins that could be poked by small fingers somebody could get a nasty shock.

I feel like always making the live side of the cable the female one is the solid choice here

*3. Is there anything obvious I have overlooked?*

My knowledge is far more in the coding side of things. I haven't done any wiring diagrams but I'm thinking maybe I should?

From Chris Bolton on the mailing list, 9 Jul 2026 15:22 UTC

Hi Rob,

My thoughts are that the barrel jack on the power supply should be okay just as long as the power supply isn't under a continuous full load.  Do you have the exact specifications of the power supply as I might question whether 15 amps is its surge rating?  Similarly, a good quality chassis mount female barrel socket wired with 15 amp cable should be okay, but not under a full continuous load.

So to be clear, even though you may have a power supply rated at 15 amps, running it continuously under full load is not a good idea.

If you do end up cutting off the power supply than yes leaving it powered down for 30 seconds or so is a good idea.

DC voltages under 30V are considered not be dangerous with respect to electric shock.

Hope this helps...

Chris

From Rob on the mailing list, 11 Sep 2026 12:56 UTC

Thanks Chris, I ended up keeping the barrel jack as you suggested.

Having finished my v91824324 stands today I'm glad I did as I can't imaging running these at anywhere near 100% brightness. I did play with the other connector types but I really didn't like them. The barrel jacks are easier and forced me to reconsider running and data lines - so now these work wirelessly instead.

Next I need to finish the CYD control box you can see in the middle that sends ESPNOW commands to the stands.

While there's still a fair bit of work to do I'm happy with the stands for now. Again, thanks for your advice, it helped me get to a much slicker design.

From Chris Bolton on the mailing list, 15 Sep 2026 06:27 UTC

Hi Rob,

Wow, the stands look splendid!  Great job👍

BR Chris