In this project I will show you how to create a custom LED sign that reacts to the loudness of your music, just like a VU meter does. Let's get started!

Step 1: Watch the Video!

The video gives you all information you need to build this project. But in the next steps you can find a parts list, schematic and reference pictures for your convenience.

Step 2: Order the Components!

Here is a list of all the parts you will need to recreate the project.


1x Stripboard: http://amzn.to/1q6WVz3

100x 5mm Green LED: http://amzn.to/1q6X3yr

1x Perfboard with copper dots: http://amzn.to/274wjQY

1x 3.5mm Audio Jack: http://amzn.to/274wv2p

1x DC Jack: http://amzn.to/1q6X999

2x LM324 OpAmp: http://amzn.to/1q6X9pK

1x 47µF Capacitor: http://amzn.to/1rAYQx7

1x 100kΩ Potentiometer: http://amzn.to/1OiIKgt

7x IRFD220 N-channel MOSFET: http://amzn.to/274wH1M

11x 10kΩ, 1x 47kΩ, 4x 1kΩ, 2x3.3kΩ, 3x 4.7kΩ, 2x 2kΩ, 1x 6.8kΩ, 1x 2.2kΩ, 1x 51kΩ Resistor: http://amzn.to/1OiIOws

1x 12V 2A Power Supply: http://amzn.to/1q6Xl8q

1x: Buck Converter: http://amzn.to/1rAYZ3t


1x Stripboard:-

100x 5mm Green LED: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

1x Perfboard with copper dots: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

1x 3.5mm Audio Jack: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

1x DC Jack: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

2x LM324 OpAmp: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

1x 47µF Capacitor: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

1x 100kΩ Potentiometer: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

7x IRFD220 N-channel MOSFET: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

11x 10kΩ, 1x 47kΩ, 4x 1kΩ, 2x3.3kΩ, 3x 4.7kΩ, 2x 2kΩ, 1x 6.8kΩ, 1x 2.2kΩ, 1x 51kΩ Resistor: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

1x 12V 2A Power Supply: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...

1x: Buck Converter: http://rover.ebay.com/rover/1/711-53200-19255-0/1?...


1x Stripboard: http://amzn.to/1Ky7A8A

100x 5mm Green LED: http://amzn.to/1SW1GH4

1x Perfboard with copper dots: http://amzn.to/1WhVmwA

1x 3.5mm Audio Jack: http://amzn.to/1WhVr3q

1x DC Jack: http://amzn.to/1NtXgmx

2x LM324 OpAmp: http://amzn.to/1WhVsnX

1x 47µF Capacitor: http://amzn.to/1SW1Q1l

1x 100kΩ Potentiometer: http://amzn.to/1WhVJXY

7x IRFD220 N-channel MOSFET: http://amzn.to/1TwZeDp

11x 10kΩ, 1x 47kΩ, 4x 1kΩ, 2x3.3kΩ, 3x 4.7kΩ, 2x 2kΩ, 1x 6.8kΩ, 1x 2.2kΩ, 1x 51kΩ Resistor: http://amzn.to/1E9uEhN

1x 12V 2A Power Supply: http://amzn.to/1TwZhPB

1x: Buck Converter: http://amzn.to/1TwZi66

Step 3: Build the LED Sign and the Circuit!

Here you can find the schematic of the circuit and reference pictures. Use those to create your own circuit. The average time to make the LED Sign VU Meter should be around 4 to 5 hours if you do not face any problems.

Step 4: Success!

You did it! You just created your own LED Sign VU Meter!

Feel free to check out my YouTube channel for more awesome projects:


You can also follow me on Facebook, Twitter and Google+ for news about upcoming projects and behind the scenes information:



<p>this is your best project with the worst explanation. You can barely see the schematics and you go really fast while soldering so no one can actually see what's going on...</p>
Anyone plz help me out.
In the scematic u have used 8 lm324 but in the images u have shown there is only 2 lm324.Please help me.Thanks in advancefor ur reply.
I really don't quite understand what it means by 'Audio' with the little arrow pointing upwards in the circuit diagram. Where is that actually connecting to? <br><br>Any help would be appreciated! Thanks.
That connects to the audio input
When I do that, the LEDs dont light up ?
<p>have you checked all the connections and made sure everything is wired up right?</p>
I'll get back to you on that tomorrow after trying different things haha, but this is what i have observed:<br><br>Instead of starting with Row7 (i.e. connecting the 1st op amp output to the &quot;Row7&quot; <br> configuration of resistors) I started with Row1 and connected the positive input to the output of the first opamp and that worked great. I went on to wiring up Row2 and found that when I connected the positive input for Row2's opamp to the output of the first opamp, the LEDs would simply not light up. However, when i connected Row2's opamp positive input to the output of Row1's opamp, they lit up fine. The only problem was there was hardly any difference between the rows brightnesses. I initially started with the row7 configuration although that yielded null results as well... <br><br>I'll get back to you with some pictures soon...
Hey dude whats up? Can you help me out? Theres the thing, i know that you are giving audio signal to the positive pin of each amp, like you show on the schematic, but my doubt is that im no sure at where? On positive pin or negative?
<p>What do you mean? The audio that comes out of the first op-amp, goes into the positive input of each other op-amp. The output from the voltage dividers goes into the negative input.</p>
When I do this, only the first row works. The only way to get them all to work is to hook (for example) row 1's amplified output to the positive pin of row 2's amplifier and so on.
<p>Hi, what was the name of the program you used for the LED layout? I keep missing it in the video. <br><br>Thanks.</p>
<p>Would I be able to connect a similar circuit to the 10x10 LED matrix?</p>
<p>It has been successfully implemented but IRFD 220 No. 7, the temperature rises as a bug</p>
<p>nice project.can you make a simple VU meter circuit</p>
Isn't that sorta, well, what he just did?
<p>We can also use LM3916, instead of op-ams, right?</p>
<p>Well, I think you could, but the schematic would need to be different.</p>
Yeah its obvious but it could be simpler
<p>Yeah, could be. I don't have any experience with LM3916's, so I don't really know.</p>
<p>Excuse me, do you have a bigger version of the schematic? I'm a bit (more like huge) myopic. :(</p>
<p>You can download it with its original resolution. Simply left click on the picture when it is maximized and you will see a couple of download resolutions on the left side. </p>
<p>Would you mind providing the schematic for download?</p>
<p>I just described how to download it</p>
<p>Oh! I mean the file of the eagle file, I would like to create a PCB for it.</p>
<p>Here's a link to a schematic I made, it doesn't look the same, but it works the same. http://www.filedropper.com/untitled_193</p>
<p>Gee! See how myopic I am? Thank you!! :) Awesome project BTW.</p>
<p>They are not the happiest currents ever.</p>
<p>These lights are either all on or all off. What should i do </p>
<p>What kind of user Alatrutstr</p>
<p>what is alatrutstr?</p>
<p> Name Transistors</p>
<p>Hi, I tried to build it by myself but for some reason only rows which are connected to pin7s of lm324 are working correctly,other rows are not lighting up at all. I already chcecked the cirucuit twice and found some mistakes which i fixed but it didnt changed anything.Can there be something wrong with the ics? I didnt use sockets for them so could i damage them when i was soldering them?</p>
<p>Can you upload the Eagle schematic file? The picture of the schematic posted here is too small.</p>
<p>Look through the comment section to find your answer</p>
<p>I can't really find IRFD220 in my county (Austria) but IRFD210.</p><p>Does it work?</p><p>Thanks :)</p>
<p>I also can't find IRFD220 in my country (Austria) but IRFD210.</p><p>Does it work ?</p><p>Thanks :)</p>
Can't find IRFD220,<br>Can i use NPN transistor instead of Mosfet?<br>Thanks :)
<p>you said that your signal is almost 2 v so you need to amplifie it to 9 right? you set the gain to be 48 isnt that wrong? explain please </p>
<p>In my country, I cannot buy <strong>IRFD220N</strong>. Can you give me another mosfet? Thanks</p>
Can I use NPN transistors instead of n-channel mosfet in this project?
<p>That looks great!</p>
<p>This is awesome. I was looking to build a project, actually it is a LED display for my mom's restaurant. This video is just great. </p><p>I loved the website. I was searching on the topic of parallax effect and that's when I first came to know about this site. This is a really helpful platform. Thanks.</p><p>I would also like to contribute, for this topic, here are few ideas of LED signs. <a href="https://www.newstylesigns.com/blog/led-signs/eye-catching-ideas-led-signs/" rel="nofollow">https://www.newstylesigns.com/blog/led-signs/eye-catching-ideas-led-signs/</a></p>
nice project ,you are awsom
<p>I really like the fact that you used voltage comparators to do this instead of a microcontroller or something else. Great job!</p>
Great LED display!
<p>WOW, this is a bit beyond me just yet but it looks cool</p><p>Well done.... John :)</p>
<p>one question: why the led side doesn't have current limiting resistor?</p>
<p>Because there are only 2V or so limited by the Buck Converter.</p>

About This Instructable




Bio: Awesome Electronics Tutorials, Projects and How To´s
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