Instructables
Picture of Sync LED to Music

This is a very basic circuit for syncing LED's to music.

There are several issues:

1. You do not need a 9volt power source, I have used 3volts and it worked

2. Depending on your speakers system setup you will have turn the volume up very loud
       - I have connected this to a Latte Ipearl mp3 player, the volume (0-32) had to be a 26    to  get the LED to start to blink.

3. Make a amplifier to correct problems with volume having to be very loud.

4. I could not get this work using headphones; it did not work because I could not get the enamel of the headphone wires, so I cut open the headphone jack and connected my own wires.

5. If you have an equalizer you can adjust the different frequencies to and the LED will blink accordingly.
 
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Step 1: Connect and enjoy.

Picture of Connect and enjoy.

Materials: (scavenge electronics if you can)

Power source - 3volts to 9volts should work
Resistor          -  220ohm, though I have used 150k and it worked
LED
TIP31 NPN Transistor  (Negative Positive Negative)

DO NOT HAVE POWER ON

1. Connect the resistor to the power and the positive side of the LED
2. Connect the negative (look for the flat side) of the LED to the center pin (collector) of the transistor
3. Connect the positive side of your audio signal to BASE on the transistor
4. Connect the negative side of your audio signal the Emitter of the transistor
5. Connect the negative side of your power source Emitter of the transistor
6. Turn on your power source, turn on you audio, turn up the volume and experiment with a equalizer (VLC player has one built in to the software and it is free)
vahire5 months ago

can i use tip41

Joe Blogs9 months ago
Just so you know NPN does not mean "negative positive negative" but specifies the type of silicon used to make the transistor.
jameswxm1 year ago
hi i tried this with 4 led strips but each strip has 24 leds on each so im guessing this circuit isnt powerful enough but i noticed the leds dont have resistors built in nor have i put 1 in so could this be the problem? cheers
wramirez1 year ago
24 leds Works ?? witch 12 V?
ehudwill1 year ago
This is the best I have seen on how to wire the led to sync with music. I have tried it myself but cannot get it to work.
deleishen1 year ago
great
mossDboss (author) 4 years ago
Before anyone comments, I do not know anything about electronics. I do not know anything about circuitry.

This instructable is a remake of what of one

zatek made http://www.instructables.com/id/Sync-LEDs-to-music/
i did this instructable. but something funny happens, when i plug it to my ipod it's works , but when i pluged to my laptop nothing brights... do you have any theory?
can you help me? :D

Thanks :D
mossDboss (author)  glomicilina3 years ago

does it work on your laptop if you turn the volume up high?

The project works with mp3 players only with the volume up real high.

Here is my theory

There is something with audio signals and speakers called impedance (I think that is the correct term), which means the signal and the speaker need to match (this matching gets into a realm I do not understand). for example not all mp3 players will match 8ohm speakers. that is just my guess

It was suggested to me to place a resistor between the LED and the Collector or center pin.

an idea i did have and might try is put a omp amp (many listed on instructables) and run the output of the amp to this circuit that, my hypothesis is that with the op amp the listening volume could remain low but the signal to the LED circuit would be high enough to flash the LEDS. I'll put it together soon and let you know. here is the instructable i followed in making to the op amp http://www.instructables.com/id/LM386-Audio-Amplifier/step3/Observe-Diagram/


Hey is it possible to use CMOS Op-Amp like CA3130E instead of LM386?
How would you amplify the signal to the LED's? I have this setup for my home entertainment center and it works awesome at a moderately high volume, but I don't want to bother my neighbors next door, just because I want to see my LED's flash to Grand Turismo at 2:00AM.

And it would be awesome if I could adjust it, so when I blast the volume the LED's aren't just full blast all the time. Thanks
mossDboss (author)  RocketBurn112 years ago
Yes, there are very simple amplifiers, I will send you a website. The amp I have made utilizes a LM386
can u also send me the amp website too??
I'll probably work on that next weekend. What if I ran a variable resistor and two or three 9v batteries on the led's?

That might exceed the 12v rating on my LED's, but then I could add a 12v voltage regulator.
ToOkiE142 years ago
atlast. thank you so much for your instruction.
i already finish my project..
dog digger3 years ago
This will work with any npn transistor. I just use a 3mm LED and a 3904 and it works great! thanks for this awesomely simple instructable!
nice ...thanks mate
zatek3 years ago
Hey man!
Just stopping by to say that it's no problem that you remade my tutorial, I think sound synced lights get way too little attention these days.
Cheers, Zatek.
mossDboss (author)  zatek3 years ago
thanks man.

I built a op amp to connect to this circuit. I had to have the volume up too loud without the amp.

I have found another circuit on youtube which has LEDS synced to different frequencies of the music http://www.youtube.com/watch?v=Yd3hzYAJzOo