Sound Activated LEDs





Introduction: Sound Activated LEDs

Ive always wanted lights to flash with the bass in my truck but the store bought lights don't work very well so I decided to build them myself. I used 100 each of red, green, and blue LEDs. I accidentally  recorded upside down cause I had to use my ipod to record cause my camera doesn't have a mic.

Step 1: Required Materials

For this instructable you will need the following tools:

Wire cutters
Small Needle Nose Pliers
Solder gun
Solder clamp
300 LEDs (for me)
60 51 ohm resistors
Wire (I used speaker wire)

Step 2: Make Holes

First you need to cut the binder to the desired shape and put the required number of holes in it for your LED array. I used 300 LEDs so I cut two rectangular pieces of binder and put 300 holes in each (1 for positive and 1 for negative).

Step 3: Insert LEDs Into Proper Holes

Next you need to put the LEDs in the holes in a pattern you like. I put them RGBRGBRGB.

Step 4:

Next you twist the ends of the LEDs together leaving the first positive and last negative sticking out to the side. Make sure you do it like in the pic or it won't work right.

Step 5: Solder the Resistors

Next solder the resistors together to make a negative "line" and do the same with the positive side.

Step 6: Attach the Wires

Next you need to solder the wire to their respected sides. I originally planed on wiring them up to a sound module but it didn't supply enough power to light up all the LEDs so I just wired them directly to my subs.

Step 7: Install

To install this I pushed needles through the board and bent them so I could slide it into the headliner.

Step 8: Final Thoughts

Overall it turned out great but it was a little brighter than I thought luckily my amp is on a switch so I can turn it on and off whenever I want.



    • Water Contest

      Water Contest
    • Clocks Contest

      Clocks Contest
    • Creative Misuse Contest

      Creative Misuse Contest

    16 Discussions

    Is there a way to do this without hooking the lights directly up to the speakers? Its for a wall art project in my house and I want to be able to move my speakers around

    Im trying to do this in my house. But I want a strip not just a square of dense leds. So I was thinking of getting 600 leds like these below Can I use them and will they work? And how do I plug them into my subwoofer with speaker wire into the line out? thanks

    stick the wires in to the amp input instead of the output they should work fine

    wouldn't running lights off the sub blow the amp? is it safe?

    1 reply

    No it wouldn't. I would be more concerned about the amp blowing the subs. Most amps put out well over over 12 volts to the subs. My amp puts out enough to run my computer if it wasn't A/C. I actually had to add a voltage regulator between the sub and the lights cause it outputted too much.

    Interesting idea, but i think there maybe a legal issue here. Flashing lights in the car maybe seen from the windows and other people may think your an undercover cop and other possibilities.. This is very risky.. Nice idea though.. maybe implement it somewhere else.

    2 replies

    people already think i'm an undercover cop cop. I drive a white tahoe with black rims and dark tint with antenna's on the roof. I removed them from the truck because the subs blew a few of the LEDs out.

    Theres a little machine called a "light organ" that listens to your highs mids and lows and sends your adjusted settings to the lights. It'll save you from your amplifier woes.

    Yes, they are wired directly to the sub which I found out today was a bad idea but I don't have any way of regulating the voltage from the subs to the LEDs. Yes I could put a voltage regulator on it but the voltage output to the subs can get as high as 80+ volts when the you turn it up. I don't want to fry the regulator.

    Well you could make a scaled up verion of this given if you find a suitable transistor that works in the specified voltage range, this way you can detach (it's not really detached, but it's enough to not fry your LEDs, OR the sub) the LEDs from the sub, and it would work as a switch! Of course, as I didn't try it, it could have other issues, but maybe it gives you some ideas on how to protect the sub, and the LEDs!

    It's interesting that the LEDs are close enough together that in your video they look white! I wonder if a somewhat more complicated circuit, for example where you wire the three colors separately with delay lines (maybe as simple as an RC), could make for interesting effects.

    Quite awesome!

    1 reply

    Thanks! I had to make the projects as compact and easy to install as possible. Maybe next time i'll tackle an equalizer made of LEDs.

    Hi, nice Instructable! A couple of things you might not know about the way the site's database/page generator works.

    First, if you don't put a regular still image as the first image on a step, it leaves the thumbnail blank (and on your intro, that means the picture on the Recent Instructables page is blank).

    Second, I see that you included an MPEG video. The Instructables site doesn't have any streaming video of its own. Instead, what they ask users to do is to upload their videos to any of the major services (YouTube, Google Video, Vimeo, Flickr, and so on), and then use the "embed code" function from those sites. When you're editing a step, you'll see a button for "add video", and with that you can paste in the embed codes and the video will appear in that step. Other than those issues this is a really cool project, and nicely written up.