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Digital Color Organ Build Help

  1. Aug 29, 2013 #1
    Hello everyone,

    I recently posted about making a color organ, in which I was going to use a circuit to process analog signals. Since then, I have decided to move in a new direction of a digital color organ.

    I would really appreciate if someone with more experience than me could give some advice and oversee my build to make sure I don't blow something up haha.

    I was inspired by this build.

    This is my plan so far.

    Using a Jack on my computer to split the audio so that I could send the signal to my speakers, as well as to a program called Max

    Max will do all the processing of the audio data, and send the information over serial to an arduino microcontroller.

    I am planning on running 6 lights on my color organ (2 low, 2 mid, 2 high), so I figure I will need 6 pins that are capable of sending a PWM signal.

    I've never worked with an arduino leonardo, but it says it can output up to 7 PWM signals.

    1. Anyone forsee any problems with this microcontroller and/or can suggest using a different one?

    Now becomes the part where I am lost.

    I would like to use 6 high power led's such as these. They are the same led's that were used in the build I was inspired by.

    Unfortunately, the build uses heat sinks I was not able to find. I found these led's, but I don't know if that helps my cause at all.

    2. I would really appreciate if someone could help me find a heat sink setup to work with these lights.

    They will be spaced out approximately 6 to 8 inches apart each. Also, I would like to add one of these optical lenses on top to more evenly distribute the light throughout my room, so a heat sink setup that would allow those to fit would be nice.

    3. Lastly, I need help finding out what driver I should use to power these bad boys.

    The original build used this driver. Compared the the other drivers on the site, this driver was muuuch more expensive. If someone could explain why this one is necessary, then I guess I will go with this one, but I'd rather not spend money on something that isn't necessary. (I am not opposed to having all of the lights the same color if that has something to do with it.)

    I know this post is kind of lengthy so I really appreciate your guys' help on this one! Thanks in advance!
  2. jcsd
  3. Aug 30, 2013 #2


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    Gold Member

    Speaking to the driver:

    You can easily hook three lamps in series to each driver on the driver board so I think it is a decent deal. It's expensive, but done. There is probably $10 worth of parts and a $5 board. If you try to build such a thing by hand you will have no end of problems.

    It is a 95% efficient constant current switching converter that can easily handle 700ma lamps. I'm not sure what other driver designs you want to compare it to.
  4. Aug 30, 2013 #3
    As far as the driver goes, is it the fact that it is tri-color that makes it expensive? Or is it just a very good driver that can provide a very steady current. (Sorry if this is a very novice question, still learning.)

    So would you suggest getting this driver for the build I am planning?
  5. Aug 30, 2013 #4
    If you decide to make your own PCB (it takes some skill and persistence, but it's not hard) you could:

    1) get normal micro controller for 3$ instead of Arduino.
    (never was an arduino fan, don't know why, i just hate the damn thing)

    2) Get 3 simple led driver chips for 6-9$ MAX! That driver is extremely overpriced IMHO.
    ON semiconductor's CAT4101 would do a great job, and all you need is 1 resistor to set the max current. That would be much better for you because chance of you burning your led is 0. While with that thing in the process of experimenting and playing around you might send a constant signal that would send 1 amp trough leds and fry them. I burned lots of transistors when i was a student, trying to read signals with my oscilloscope, and shortening something with the probe. Some of them burned because of mistakes in my calculations. But that's how engineers learn.

    3) You will need few resistors, caps, wires etc but that's cheap, you can buy that in your local electronic store.

    4) If you decide to do everything by yourself it will take you little longer than if you buy everything but you will learn more about electronics, and that alone is worth the effort IMO.

    I have to point out that you will need some tools. Can't do much without tools.
    Also if you really are into arduino you can use it, and instead of their driver take 3 chips i recommended and put them on a small protoboard, they are in SMD but there are conversion boards to make them trough hole, or just make the small pcb for the driver only.
    Last edited: Aug 30, 2013
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