anyone know of any issues with distance between power supply and controller or power lines and data lines? I have a 42v power supply that delivers power to buck converters , will the higher voltage potentially cause interference with either the controller or data lines?
Most distant setup was about 15 feet from MCU and PSU to start of strip with 5V, and the signal line was actually one of several fanned out from one MCU pin to several strips running in parallel. The MCU was a ESP01 on a solderless breadboard (connections not without their own flakiness!) providing signal through a cheap standard level shifter. Used 18 gauge wires for power and signal, and 1000uF capacitors at the breadboard and at the strips, I think. I don’t know if that was the ideal setup, but it worked. Probably pulled only 3-5 amps to 130 leds. It ran well.
@Stephen_Kramer thanks but im more curious about power supply being to close to controller and data lines, and possibly causing interference… i have two options of where to put the power supply, so im just hedging my bets and setting it up so i can put it in either spot.
Will totally depend on the digital signal integrity capability of rejecting power supply ground currents… … referring to Common Mode Rejection
Be careful to choose the correct buck converter. Most of the check converter are only stable up to 32 or 38V input voltage. Sometimes they react a little bit strange if the input voltage is significant above the specified input voltage. This could lead to problems.
But generally you can say :
The closer the better. But don’t forget the big capacitor close to the first LED. A small extra bypass capacitor (100nF) in parallel cost nothing and adds a little bit safety for higher frequencys.
@Sven_Eric_Nielsen Thanks… i originaly purchased a 12v powersuppy some buck converters labeled as 12v-60v to 5v 10 amp, but it turns out the buck converters are 20v-60v so i traded the 12v powersupply in for a 42v one. i have a 1000nf capacitor at each buck converter before it connects to each led strip. thanks for your thoughts.
@John_Sullivan i will have to do some research on what this means. thanks
@Eric_Inthecircle
Do you mean 1000nF or 1000uF?
1000nF is by far not enough. It’s better to put 1000uF in.
Most of the buck converters generate a huge voltage spike for a few microseconds when you turn them on. This can kill your first led. I have learned this the hard way 
oh i probably mean 1000uf, i got whatever adafruit suggested. Turned my installation on with this setup last night for the first time and everything seamed to work quite fine.
The voltage level itself is unlikely to have any effects.
There is so much myth out there wrt the capacitors.
I found this to be the best explanation: What is it for and how to use it.
@Juergen_Bruegl
You’re mixing 2 different things here. One is noise. That’s what the bypass capacitor is for. The other thing is overvoltage compensation. That’s what the 1000uF capacitor is for.