I used to think I knew a lot about
LED tape, but then I started reading what the other members have written. So here's my two cents:
For the record, there are
LED strips that are just LEDs in series and are controlled by
PWM and then there are
LED strips that have decoders and
PWM drivers of some sort built in (Neopixels, WS2812, APA102,
etc.). LEDs in series are all controlled at once (the whole string is one color) and the others are addressed individually in a very clever way. There are other strings (as noted above) that are direct
DMX controlled but I've not yet played with them. The
DMX controller linked to above is for simple strings of parallel LEDs and works really well (I have several). The "addressable" LEDs require some sort of controller -- either purchased or home-built (
Arduino, Raspberry Pi,
etc). There is a
great project on the Internet that does wireless/streaming
ACN over wifi and controls strings of WS2812 LEDs. The hardware is cheap and can be built easily at home. I have built a couple and on a closed wifi
network, they are very reliable. If the link doesn't work, Google "ESPixelStick". Strangely enough, the Christmas lighting and Halloween forums are full of information on how to
roll your own
system.
One of the differences between Aliexpress LEDs and LEDs from more mainstream sellers such as
Enttec is the
thickness of the copper traces in the
power lines. The Chinese direct-sales LEDs have thinner copper
power runs and are therefore susceptible to
voltage droop at the end of a run unless you supply both + & - in parallel with thicker wires and "inject" it along the way. An
RGB LED at full brightness will draw about 60mA, and that adds up quickly. The
voltage drop over the length of a string of LEDs with underdimensioned copper
power traces will cause the pixels towards the end to be be increasingly reddish (blue LEDs turn on at a higher
voltage than red ones). Another difference is color matching. In my experience, Chinese direct-seller LEDs are more variable in color for a given input. This can be calibrated out, but the math to do it is beyond me. A couple of years ago at
USITT, some students from Stanford showed
an LED video wall they built from
LED strings bought directly out of China for a ridiculously low price. They calibrated each
pixel individually for uniform color. Very impressive.