TerryK
Retired Elf
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Do you recommend using 5V or 12V strings?
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There is not an easy quick answer to this. It is a personal choice I think.
I have tested 12 Volt Regulated pixels and they are more immune to voltage drop than either 5 Volt or 12 Volt Resistor pixels (WS2811 strings). Keith in one of his videos indicated that the 5 Volt pixels are more immune to flickering/erratic pixel illumination for long length data line runs. While I have not played or tested long data line runs, I agree with Keith's explanation.
I use 12 Volt Regulated pixels. I do have some 12 Volt Resistor pixels but those will be replaced over time. I chose 12 Volt because I like WS2815 strips which are only available as 12 Volt and I did not want to have a mixed voltage display.