Just wanted to mention here that as an alternative to the level shifters sold under that name on banggood and aliexpress, you can apply TTL ic's like below. I have tested these on my setup Rpi 3B+ on HyperBian alpha7 with WS2815. The advantage of these buffers over the level shifters is speed and they have built in logic to keep the signal clean.
- Quad buffer SN74AHCT125N
The Rpi output is connected to the input, the Output Enable connected tp GND. The output is connected to the LED strip data line.
- Quad AND gate SN74HCT08
The rpi output is connected to one of the AND gate inputs, the other input is connected to VCC (5V), the output is connected to the LED strip data line.
I also use 1k resistors on all input and output lines as a precaution to spikes and shorts.