Making it brighter?

Hello everyone.
I've completed construction on my saber electronics, I just need to fine tune everything.
What I'm working with:
Red-orange Luxeon LED http://www.luxeonstar.com/Red-Orange...r-01-h2070.htm with collimator lense
Obi-Wan Feel the Force soundboard
The cheaper speaker from TCSS (called the 'premium speaker')
6 AAA batteries (so 9 volt, if I'm adding correctly)
4.7 ohm 5w resister, on the negative wire of the LED
My problems are twofold:
The LED only lights up approximately 5-6 inches of the blade (which is a thick walled trans white). The rest is very pale. I've tried putting a few wraps of clear cellophane in the blade, but that only made the whole thing dimmer. Would it be safe to remove the resister, or would I risk burning my LED?
My second problem is the speaker. Is 9v too much for it? It sounds very odd, getting louder and softer at weird intervals. It sounds stressed to me, which is one reason I'm thinking of taking the resister from the LED, so I can put it on the speaker to make it sound better.
Thanks for reading, and I welcome suggestions and advice. If there is anything unclear about my construction please ask.

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Originally Posted by Aziara

Hello everyone.
I've completed construction on my saber electronics, I just need to fine tune everything.
What I'm working with:
Red-orange Luxeon LED http://www.luxeonstar.com/Red-Orange...r-01-h2070.htm with collimator lense
Obi-Wan Feel the Force soundboard
The cheaper speaker from TCSS (called the 'premium speaker')
6 AAA batteries (so 9 volt, if I'm adding correctly)
4.7 ohm 5w resister, on the negative wire of the LED
My problems are twofold:
The LED only lights up approximately 5-6 inches of the blade (which is a thick walled trans white). The rest is very pale. I've tried putting a few wraps of clear cellophane in the blade, but that only made the whole thing dimmer. Would it be safe to remove the resister, or would I risk burning my LED?
My second problem is the speaker. Is 9v too much for it? It sounds very odd, getting louder and softer at weird intervals. It sounds stressed to me, which is one reason I'm thinking of taking the resister from the LED, so I can put it on the speaker to make it sound better.
Thanks for reading, and I welcome suggestions and advice. If there is anything unclear about my construction please ask.

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If you remove the resistor, you would probably fry the LED.

As for the rest, now that I have seen which board you are using, I don't know much about the economy boards, but I would *guess* that unless they originally could take 6AAA batteries, you could be giving it too much voltage. Also standard batteries doesn't have a reliable discharge rate (as opposed to Li-ion batteries) so that could be a lot of your issue as well. I'll wait until some others with "Econo board" experience chime in here.

You have a red/orange Rebel LED. Forward voltage is 2.3v, and it should be run at no more than 700mA. Overdriving the warm colored Rebels will cause them to decrease in brightness. With your current resistor, you're giving that LED around 1400mA. Get a 10 ohm 5 watt resistor, and your brightness should significantly improve.

I'm thinking 9v is too much power for your soundboard. I don't know the specifics on your soundboard, but I'm guessing you're giving it too much juice, and that is affecting your sound. I'd drop the whole thing down to 6v before something gets fried. If you do, you'll need to recalculate the resistor for the main blade.

http://led.linear1.org/1led.wiz

Ah! I understand. I thought--more power=more lumens. So I actually need to decrease the power level. So to make 6v I should likely put in 2 battery blanks to make 4 AAA instead of 6(unfortunately, it looks like TCSS only has AA dummy batteries). Hopefully this solves the sound problem as well. I had attempted to run everything off of only 3 AAA, the sound was great, but the LED was very dim. Perhaps I have the wrong resister?
I ran 6v through that link you shared and it said 'The wizard recommends a 2.7 Watt capable or greater 5.6 ohm resistor. The color code for 5.6 ohms is green blue gold.' Also, the diagram shows the resistor on the positive wire, not the negative. Would this make a difference as well?
One more thing: is there a right and wrong side to a resistor, aka positive and negative? The people at radio shack only fussed at me and said 'I should learn these things'. Thank you, radio shack, that's what I am attempting to do by asking these questions.

For many LEDs, you can give them more power and you will gain brightness (at the expense of LED lifespan). The Rebel warm colors (red, amber, red/orange) are an exception to this rule. Other brands such as LEDEngin can be overdriven for extra brightness no matter the color, as can the cool colored Rebels (green, blue, cyan).

Most of the people at Radio Shack are not knowledgeable about such things. We are. :) Resistors do not have a polarity. You can run them either direction, and they can go on either the positive or negative line. Either way is fine, but I always recommend to pick one, and be consistant.

Thanks for your help. And you're definitely right about Radio Shack. I think they simply get huffy when you ask them something they don't have an answer to. That link you gave to calculate which resistor to use is definitely being bookmarked! I can see that coming in handy often.
I did figure out why 3 AAA was too dim (the reason I originally tried only 3 was because the toy I removed the soundboard from ran on only 3) When I entered the info for using 4.5 volts, 'The wizard recommends a 1.6 Watt capable or greater 3.3 ohm resistor. The color code for 3.3 ohms is orange orange gold.' I suppose using the 4.7 ohm 5w was much too strong. Perhaps I will try a 3.3 ohm 5w from TCSS with only 3 AAA and see how it goes. I hate ordering for such a small thing, so I'll likely wait until I've accumulated a bigger order.

That sounds like an excellent plan. Running too much power through your soundboard is a recipe for a cooked soundboard. Hopefully it hasn't suffered any permanent damage from running at 9v instead of the expected 4.5v. I'm honestly surprised that the LED didn't blow out when you turned it on.

6 Volts is definitely too much power for your circuit. That soundboard runs off of 4.5 volts which would be 3 AA Alkaline batteries. Likewise the forward voltage of the Red-Orange LED is likely less than 3 volts, so you want to uses a more appropriate resistor. May I suggest you try using AA's instead as they will give you better run times. AAA's in most builds won't last you too long. Or an even better battery solution (if your hilt design can accommodate it) would be 4 AA NiMH Rechargeable batteries for a total voltage of 4.8. With the proper resistor, this should be more than sufficient to power your LED and soundboard, give you plenty of run time, and plenty of brightness without blowing your LED or board.