Add impressive backlight color effects to any TV or monitor with this easy electronics project.

The sound-reactive DIY RGB LED strip that we are going to build reacts to the music or sound coming from your TV, home theater, or any device. Besides it being reactive to the sound, you can also choose from 118 different lighting effects. You may also create custom effects.

Once built, you can use it as ambient light and install it behind the TV screen or on your gaming PC, even if your motherboard doesn’t support RGB or ARGB (Addressable RGB).

For this project, you will require the following:

Soldering skill is required. However, if you don’t have any prior experience or need help in getting started, refer to our previous guide to learn how to solder.

For this project, we will use the WLED Sound Reactive project on GitHub.

Once the firmware is flashed, you can connect the WS2812B ARGB LED strip to the ESP32 or ESP8266 board. You may connect the ARGB power input directly to the ESP board's VIN and GND pins or use a separate power supply to power the LED strip separately but with common ground.

Refer to the following diagram and table to pair the RGB strip and the mic to the ESP module.

If you don’t have a power supply or don’t want to invest in one, you may pair the LED strip directly with the NodeMCU or ESP32 and power the ESP using a micro USB cable. Although this works, it may damage the MCU and thus is not recommended.

Once you have connected the mic and the WS2812B LED strip to the ESP board, connect the 5V power supply to turn on the device.

You can now control the LED strip with the WLED app and change effects, brightness, etc. You can also adjust the sound sensitivity through WLED settings based on your needs. To adjust the sound sensitivity, go to Config> Sound Settings. There are two settings available:

If you are using INM643, type 35 in Squelch and 12 in Gain.

After entering the values in the Squelch and Gain fields, tap Save. You can play with the settings until you get the best experience for your setup.

Under Effects, you will find 15 sound-reactive effects (marked with *). You can change to any or choose a non-sound-reactive effect. The *Noisemeter is recommended for most. You may choose your palette to change the color or create a preset using a combination of palettes and effects. Further, you can change the effect speed, intensity, and LED brightness to customize the effects.

You can set up Home Assistant to automate this DIY smart sound-reactive ambient light, and control effects, brightness, and other settings from a single panel. It also gives you remote access to all your smart sound-reactive ambient lights. Besides, you can enable MQTT or emulate the strip as Philips Hue (under Config > Sync Interfaces) to control the strip using the Alexa voice assistant.

Congratulations: you have now built a sound-reactive ambient backlight for your TV or monitor. If you want, you can set up multiple WS2812 ARGB LED strips in your room or house and sync them all (via the built-in UDP protocol support) to play the same effect simultaneously with just a few taps. These DIY strips can be controlled individually or in a group using a dedicated Android app available on the Play Store, as discussed in this guide.

You may also use voice assistants such as Alexa to control the RGB strip, change brightness, or color. Further, you can add this in Home Assistant to control all your RGB strips from a single dashboard.

Ravi is an expert tech explainer, an IoT enthusiast and Linux lover with a background in big data and app development. He spends most of his weekends working with IoT devices and playing games on the Xbox. He is also a solo traveler who loves hiking and exploring new trails.

Join our newsletter for tech tips, reviews, free ebooks, and exclusive deals!