anyone done this before? seen some articles/vids but seems like they are to factory speakers without an amp

will doing this cause any issues because obviously they add a slight resistance but is it enough to affect what the amp would see?

 

Buy a colour organ. It'll convert ac sound to dc output. Then you can run the LEDs off the output.

My opinion on it is that it's annoying and distracting. But to each his own.

 

leds run off 12V DC... so you cant connect them to the positive and negative speaker terminals...

just run a 3 prong switch (constant 12v, switched 12v, ground) to all your leds

 

If you wire them to the remote and ground of the amp it should work, unless you're goal is for them to play with the music, in which case just get a music sensor light bar thing from walmart.

 

so i guess wiring a resistors to get the lower voltage would be a no go inline with the speaker

 

That's right. However you could do it by wiring them in parallel with the speaker. To do this you would want a rectifier, series resistor and maybe a zener (if you're connecting it to a big amp). If you're serious about having it pulse with the music I can draw you a simple schematic of how it needs to be done.

 

The only thing you will need to wire LEDs in parallel with your speakers is some small resistors to ensure you won't burn the LEDs out.. no need for anything else..

The value of the resistor will depend on the max operating voltage of the LED and the voltage the amp is putting out...

With that said, if you are only running say 50 watts a side and you buy 12v LEDs you should be fine without anything else...

 

While a bridge rectifier is not needed, a reverse voltage blocking diode is necessary because a LED cannot take the full output voltage in reverse. Either that or a reverse bypassing diode would work too. LEDs typically can only take 5v in reverse.

Example Datasheet

PS: a bridge rectifier would help make the LED brighter at low volume levels, given the log nature of volume.