That's not quite I started with C on the bottom half all the way to s and the back to m in "Christmas" then to the top of Y to the M on Merry where it double back along the bottom to the m of Christmas where it go along the top of "Christmas" back to C not forgetting the dot in i where it just...
I placed the lights the edge of the letters and then used the light Show Hub https://www.lightshowhub.com/tools/xlights-custom-model-builder to form a model of the lights by counting each pixel and forming each letter as a sub model and then created Groups like Merry, every second letter and so...
I used PETG and CA glue to join it together, haven't glue the top cover on as yet but might use hot glue so as it is not to hard to pull apart if I need to get to the LED's.
The LED,s are hot glued in place.
Also I might plug the holes from each letter to stop LED color bleed from each letter...
You write up got me to give it a try with what I had at home and this is what I end up with
Was short by a couple of pixels but it appears alright
I also mount it on a board so I could mount it outside and not break in the wind
The one on thinggiverse should fit as it has slots for the screws on the side to line up with the screw holes but I am not sure the mount holes for the board are the same as the baldrick
Looks great,do you have a photo of how you installed your LED to these and did you set up each letter in XLights so you can run each letter at a different color or are you going to just run it as one item in your display
I under stand that you need to set up the color light card first with LED Vision before trying to run the matrix from FPP
This is one of Greg old you tube that might help you
View: https://www.youtube.com/watch?v=L4lHbwUszAs&t=557s
You could just use a buck invertor to drop the voltage down to 12V - 5V and use the set up I show you and run the amplifier direct off the 36V as you can use the control circuit to just cut the speakers and not the supply to the amplifier
Hope this helps you out
I used a double throw double pole relay (DPDT)
As you see it cuts the speakers off but the amp stay on, also it turns the push button LED off when the speakers are running