Well, I am going for v3.0 of my home theater. v1.0 was in a house we sold years back, and it was called the "Starlight Theater". It was pretty cheap to say the least, but I liked the name. I even had a starfield ceiling, but it was, again cheap, and made out of Christmas lights...

V2.0 is where I am now. Axioms, good A/V gear, etc. Definately not cheap. Problem is that it is in a shared area with a family/game room. Light problems, less-than-ideal sound due to room conditions.

V3.0 is really moving what I have now into a new dedicated theater room. I really want to use a custom made sign I had done back with the V1.0 Starlight Theater, so I need a star ceiling again....

Anyway, I was looking at fiber optics, and most of the "kits" cover a lot more area than I am looking at. I am just looking for enough for a small 4x8 part of the ceiling. So, for cost reasons, I am looking at LEDs instead.

Here are my questions:

Do the LEDs get wired up in "series" (one LED connects to the next, which connects to the next, etc)?

If I get a power supply made for LEDs (converts household AC to 12V DC) do I still need some sort of resistors or anything, or is that the point of the power supply?

Any other thoughts?

LED's should be in parrallel with each other, from a strict electrical sense.

No idea if this is what you need.
http://www.del-lighting.com/led_mini-light_kits.html

LED Link

Best LED store on the net, tons of information too.

Thanks FordPerfect for the link. Sounds like one kit would do it for me, but it is $215 for the kit. I don't mind all of the hours of wiring up my own self made "kit", plus I could get more variation in blub size/color. I would be looking for a mix of white 3mm, white 5mm, blue 3mm, and UV 3mm. Many of these are available in self "blinking" so I would mix in various bulbs that blink with the ones that don't. That should provide a starfield that has various sizes (just like stars at night), plus stars that look a little distance away (blue) and a lot further away (ultraviolet)...

Seems like parallel wiring is the only way to go (thanks INANE, and danmagicman7 for the link). Looks like it could be done in series, but about 3 LEDs in to the circuit, there wouldn't be any voltage left, so it really wouldn't work. So to do it in parallel, I would need a lot of wire, and resistors for most, if not all, of the LEDs to get them to accept the common source voltage.

Thanks guys!

OK. According to the information and calculations I came up with (thanks to all of the good information you all pointed me to), it looks like I need a 12VDC power supply putting out at least 45 watts for my 128 (about) LED setup. (The LEDs come with resistors to get them to work with 12VDC)

So, where do I get a power supply for that? Could I simply use a PC power supply? If so, I could use the 12VDC from it, or better yet, could I use the 3.3VDC and not need resistors?

Here is an example of the specs of one PC power supply. Does anyone know if this would work?

Voltage times Amperage equals Watts

So that 12V rail says 10Amp which is 120Watts... should be fine, cept is that an AT or ATX power supply? AT has the power switch on it, ATX needs a signal to turn on and off.

I don't know about that... APC seems to make a big deal about Volt Amps (Volts * Amps) not being the same as Watts. But I'm just going off of my interpretation of their site--could be wrong.

Remember PC power supplies usually have a MINIMUM draw requirement in order to regulate... (usually around 10% of rated watts)... I found that out when I used a 150W AT power supply to run the coin reject lamps (#45s) and fans (80mm and 60mm) in my MAME arcade cabinet... originally I wasn't drawing enough to regulate the PS... was swinging between 3v and 45v on the 12v line. Can always chuck a resistor in to get the minimum if necessary... course, that's just burning off power for heat, but...

Bren R.

In reply to:

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ATX needs a signal to turn on and off.

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And you have to hold low the Power Good pin (pin 8 - look at a schematic, though... ATX PSes aren't numbered with normal nonclemature - pin 8 is bottom row... 3rd from the left or right, depending if you're looking at a plug or socket)

Bren R.

Quote:

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Voltage times Amperage equals Watts
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<br>So that 12V rail says 10Amp which is 120Watts... should be fine, cept is that an AT or ATX power supply? AT has the power switch on it, ATX needs a signal to turn on and off.

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I could just wire up a on/off (momentary) switch to the power supply instead of to the outlet (toggle switch) that the power supply would be plugged in to. Shouldn't be a problem either way.