First thank you everyone for your advice and related links.
I've tried to learn all I can in a short amount of time about LED's and basic electronics, I've even bought a radio shack electronics learning kit.
Let's say I'm making an 512 fixed color LED array, I would like to use 128 red, 128 blue, 128 green and 128 purple fixed color LED's. It would be divided up into groups of 4 with one of each color. I have learned that each color uses a different voltage so I'm afraid that constantly outputting 4 rapidly changing voltages might be difficult?
The only other alternative I think would be rgb LED's which, always?, use a pwm signal to achieve desired color. Here I'm afraid that a pwm signal would slow down how fast I can strobe the LED's thru the desired color pattern since the pwm signal is also constantly pulsing many times per second. In this case I'd only need 128 rgb LED's to be the equivalent of the 512 array since one rgb led can do all 4 colors. In this configuration all of the led are on at one time, just constantly changing between 4 colors.
I'm open to doing it either way. I figure it would probably come down to tradeoffs between costs, speed and design complexity. Eventually I'll probably experiment with both approaches to see what's best overall.
The WS281B look way cool and very functional and keeps the led cost down to around $50 or $100 if I can still very rapidly strobe them if they use pwm.
I have previously looked at ur products Crossroads and suspected they might do what I need but wasn't sure how many led they could controll or how fast?
I've also looked at 555 timer, shift array IC, fpga, led drivers, DMX controllers and much more. I just don't know enough yet to know which direction to proceed. I figured an Arduino might be a good place to start learning and moving forward with this idea.