I have a set of multi-color leds... the only problem is that the red output is pitiful (and unbalanced) compared to the blue or green. This causes the colors not to mix very well. is there anything i can do to make the red output brighter?

 

The only way you can make the red brighter would be to supply more voltage to it. If theres individual resistors by color, you could substitutes the red's resistor for one with less impedance. Ex 1K ohm -> 700 Ohms

or if there isnt individual resistors per color, you could install some on the blue/greens to make them dimmer... this would in effect make the red stand out more albiet lowering overall output.

 

would I at some point run the risk of burning it out?

 

Good question, and yes leds can and do burn up. You'd have to contact the manufacturer to know the voltage limitations of your particular leds

 

Not to be picky, but impedence is related to a resistance and reactance, such as the combined resistance and inductive reactance of a speaker voice coil. In the case of a simple resistor, it is just resistance. It will shorten the life of the led to run it at a higher current. So be prepared to change them more often. Too much current will burn them up pretty quick. Figure it using the following. I = (Vs - Vl)/R, where I = current, Vs equals the total applied voltage to the circuit, Vl = forward bias voltage of the led, and R = the value of the resistor in line with it. Just try not to go too far over the rated current for the led. Hope this helps!

 

Oh, and I forgot, an LED is a constant voltage drop, which means that if you apply 5 volts to a 3.3V led, then the LED will still drop 3.3V and the rest of the circuit will drop the rest... which explains the formula above better. The rating you need to look at is the forward current rating.

 

I was waiting for you to catch me one of these days in a terminology slip up engifineer. Youre correct, in this case it would be simply resistance.

 

had to pick on it..... hope i didnt offend!