The article is being published in collaboration with JLCPCB. They supply high quality PCBs at a very reasonable price. They also can provide SMT circuit assembly.

We thanks to our sponsor JLCPCB https://jlcpcb.com/RTA for sponsoring us PCBs for this project circuit.

Thanks To JLCPCB.

$2 for 1-4 Layer PCBs.

Get SMT Coupons: https://jlcpcb.com/RTA

In this project, we’ll teach you making music activated LED light circuit. This sound-activated light is designed to change its LEDs' color and orientation based on sounds picked up by an internal microphone. Based on the music, the lighting systems will determine the speed and color of the lights, and flash and strobe accordingly.

This circuit is using 50 LEDs they will blink one by one when there is music. The circuit is built around a CD4017 decade counter IC, the output of the first IC is received at the clock input of this IC. This IC is very useful and beginner-friendly it provides 10 outputs in a circuit.

Applications and Uses -

Component List -

To make this wireless power transfer circuit, we might need some electronics component.

All components list have been given below –



Component List –

Transistor Pin Out -

A transistor is a miniature semiconductor that regulates or controls current or voltage flow in addition amplifying and generating these electrical signals and acting as a switch/gate for them.

In a simple word a transistor is a solid-state electronic device that is used to control the flow of electricity in electronic equipment and usually consists of a small block of a semiconductor.

Its 3 legs pin-out can be seen above.

Transistor Feature -

Part No – BC 557


CD 4017 Features -

Hardware of SMT Project Circuit - 

To make this mini flip-flop circuit, we might need some electronics component. JLCPCB has its own parts library. JLCPCB has 200k+ in stock components, 24 hours rapid SMT assembly.

You can check SMT parts library here - https://jlcpcb.com/parts

Circuit Connection – Step 1 

To make this music activated light circuit, 1st we connect CD4017 IC with PCB board. We connect 2no, 4no and 8no leg of IC and connect 3no and 9no leg of IC. Then we connect 33 KΩ resistor with 3 no leg of IC and then connect its other terminal with 6no leg of IC.

Now we connect 1.5 KΩ resistor with 7no leg of IC and then connect its other terminal with 8no leg of IC. We utilize JLCPCB (https://jlcpcb.com/RTA) to printout our PCB.

Circuit Connection – Step 2

To make this circuit we are using 50 pieces LED light. We divide this led by 10 and then each side got 5 led. We make parallel connection in this 10 side led and connect all LED negative legs with 8no leg of IC.

We connect all transistor emitter leg and connect this emitter leg with 9no leg of IC.

Circuit Connection – Step 3

If we count this transistor in 1 to 10, then we connect its 1no transistor “Base” leg with 1no leg of IC, 2no transistor “Base” leg with 18no leg of IC, 3no transistor “Base” leg with 17no leg of IC, 4no transistor “Base” leg with 16no leg of IC, 5no transistor “Base” leg with 15no leg of IC, 6no transistor “Base” leg with 14no leg of IC, 7no transistor “Base” leg with 13no leg of IC, 8no transistor “Base” leg with 12no leg of IC, 9no transistor “Base” leg with 11no leg of IC and 10no transistor “Base” leg with 10no leg of IC.

Thanks to JLCPCB for offering us, this SMT PCB circuit.

Circuit Connection – Step 4

Now we just need to connect audio cable and power source cable with the PCBs. We connect audio “G” cable with 4no leg of IC and connect “L” cable with 5no leg of IC.

Just need to connect power source with the circuit. Connect DC positive cable with 3no leg of IC and connect DC negative cable with 2no leg of IC.

Soldering and Cleaning -

Neat and perfect soldering is an important part of all kind of PCBs. Since soldering, you should remember that, there should not be any kind of short circuit. After soldering all leg, we cut-off the extra leg of all electronics component.

Steps to Order PCBs from JLCPCB - 

If you complete design of your PCBs, then it is time to order PCBs. To order best quality PCBs, just visit JLCPCB and click on the “QUOTE NOW” button.

Since 2006, JLCPCB continuously driven to become more efficient and to reduce costs. They promise to offer customers the most economic PCBs forever. JLCPCB makes cheapest but top quality PCBs possibly because of scale effect, extremely high production efficiency and less manpower cost. You can order minimum 5 pieces PCBs for only $2 costs.

To order PCBs, make your Gerber file. Then drag and drop the Gerber file on the following box.

Click on “Gerber Viewer” button you can check the PCBs design. Make sure everything is good, then choose color, quantity and order your PCBs at very reasonable prices.

If you are a new user, then you can order 10 pieces PCBs, costing only $2. To place your order click on “Save to Cart” button. Confirm your shipping address and shipping method.

Steps to Order SMT PCBs From JLCPCB -

Shipping and Billing - 

JLCPCB supported Payment method - 


Confirm PCBs Order -

To confirm your order, pay your payment. Then accept PayPal, Credit/Debit Card, Prepaid Wire Transfer. To manufactured your PCBs, it’ll takes about 2 days. DHL will be fastest shipping method to arrive your ordered PCBs at your location.

All PCBs were well packed and quality was really good. Thanks to JLCPCB for best quality PCBs.