I was wondering if it would be very hard to make it so I can dim about 150 leds, 50 red, 50 blue, 50 green, by color so I could make a graphic equalizer out of them, so that red would be the highest frequency and blue would be the lowest. How hard would this be to do?
What exactly do you mean by 'computer controlled'? Is this something for a pc or is it a microcontroller project? What aspect of the project would be controlled? Also, when you mention 'graphic equalizer', do you mean to use these just as static indicator lights on eq knobs, or do you mean 'spectrum analyzer' that displays changing frequency strengths in real time?
I would like to program it so it has either an audio in and a micro controller or wired to a parralell port or something of that nature. So I can fade the 3rgb leds through a range of colors, so that they are all one color like a visualisation. so if the audio on my computer is mostly high frequency it will be red. If it is mostly low it will be blue.
You would need to make a program to perform FFT to find certain frequency ranges at certain times or find a 3rd party library to help you. It would be similiar to how Winamp does its equalizer visualization except the output would be to I/O port on the computer. PWM would be a way to control "brightness" or utilizing a Digital Pot would another.
How you approach this is going to be based on what experience you have... Microcontrolled vs parallel port are two different worlds. Both of these methods could become fairly complicated, particularly from a programming point of view. I hope not to offend you, but I get the impression that you do not have experience with either microcontrollers or pc programming (C, .NET etc). Should this be the case, the easiest solution would be to get a kit like the CK109 and hack it a bit to suit your purposes. If you have experience with microcontrollers, National Semi's LM4970 is probably a one chip solution, provided you can work with such a tiny chip (LLP is only 4mm x 3xx). The parallel port thing could be done with some code hacking, I'd start by examing the Winamp example code and modiding it to control lpt pins rather than drawing on the screen. The example code demonstrates some fft routines to derive frequency data.
Well, I know some programming, Mostly php and java though, but yeah it might be over my head and yeah I was talking to my dad and he said the frequency ranges would be hard. (hes an acoustical engineer). Found this, http://www.rgbled.org/ might look into it abit more. Maybe try and learn Serial Protocol.
That's a neat project, but it really doesn't do what you were originally asking... Check this page out for another passive solution that is audio controlled...
