7.4v 18650 pack, PC 2.0, Tre Cree XPE-2 R/R/W, no PEX yet, what resistor do I need for this? I've watched Madcow's video with a PC 1.6 and B/B/W and he used a 10 ohm 2 watt, according to some of the calcs I've seen 4.7 ohm 4.7 watt is what it called for.

I'd also like to get stats for a crystal chamber started. I'm debating between using a white vs red LED for this with the gem either clear or red in color. With the white iirc the leds were rated for 3.0 - 3.2v and the reds were 2.0 - 2.2 or so. Would the whites even need one, or maybe a 1 ohm 1 watt? Would the red need anything given in theory the sound board is only putting out 3.3v to the bulb, so again a 1/1 or a 2/2 maybe?

Also what is the SMD resistor the current PEX claims to want and has pads for? Is this a necessary thing? Do I care about it?