LM3914 based LED VU Meter its very simple and effective. Looks great when in action. It runs from 9v to 12v power supply. As like my all other projects its not just a idea or diagram its tested in all ways works just fine. Use 5mm Led looks great you can also use 3mm but the bigger the better. its a mono vu meter if you want stereo than just put  two circuits side by side. So build the circuit in good quality PCB and if you face any problem than just gave me a call i am always here to help. Happy building
<p>Excellent tutorial. Useful for my students.</p><p>I built this back in the early 1980s when the LM3914 first came out. I made a wearable sound meter so I could walk around and display soundwaves through Persistence of Exposure. Lots of fun....</p>
<p>wow thats hopeful ...keep it up </p>
<p>Hiya - You don't need the LED current limiting resistors - the LM3914 has LED current control which is set through a single resistor. Also VU meter would be better with LM3916 as it is logarithmic. </p>
<p>ok boss</p>
<p>Hi, it looks realy interesting i want to make it, but can you please explaine to me what is mean wire going from middle of the 5k resistor to RHI? And Am I understand this resistor is not conected directly from minus to plus? I do not realy get what is resistor mean :).<br><br>And I hope i can use 12v power source with LEDs:<br>Forward voltage(V): 2.0-2.2<br>Current(mA): 20<br>Am I right?<br>And last question will be resisotrs still 1K befor each LED?</p><p>I am new with making some electronic devices. I just made something with TIP31 But this looks better.</p>
<p>hi mayby im late :p </p><p>you can follow these tuto <a href="https://www.instructables.com/id/Mini-LED-Volume-Towers-VU-meters/" rel="nofollow">https://www.instructables.com/id/Mini-LED-Volume-To...</a> </p><p>or <a href="https://www.instructables.com/id/Tower-Led/" rel="nofollow">https://www.instructables.com/id/Tower-Led/</a></p>
<p>Varaz plz say it again clearly, actually i don get you ,what you are trying to ask ?</p>
<p>I am trying to build a large VU meter. I would like to run about 100 LEDs per level of sound. So with them all on there would be 1000 LEDs lit up.</p><p>Can you help me with how I would modify this circuit to be able to handle the power input I need to have to run those. The LEDs I want to use run on 12v.</p>
<p>Hi kyrosroy </p><p>I don't know if it's possible to drive 100 LEDs. Here is a tutorial to drive 20 LEDs</p><p><a href="http://chemelec.com/Projects/Volt-Meter-2/VoltMeter-2.htm" rel="nofollow">http://chemelec.com/Projects/Volt-Meter-2/VoltMete...</a></p><p>share your work when it's finish thanks</p><p>hope i can help you. </p>