How To Build Your Own Portable DIY MP3 Player

MP3 players are easily available in the market. But what’s the fun of buying when you’re building one for yourself. If you’re a DIY enthusiast, this project will help you build a battery-powered mini MP3 player with a 3.5mm headphone jack (to plug in your headphones or aux) that you can take with you anywhere. can take to. You can also choose to build a portable MP3 player with a pair of speakers.

In addition, you can interface this module with Arduino or other microcontroller with RX/TX capabilities, such as ESP8266, and integrate with Home Assistant to play voice alerts or sound an alarm.

What is DFPlayer?

DFPlayer is an inexpensive mini MP3 player module that can play music or audio (MP3 files) with direct output to the speaker. You can use this module for different projects. It can be used to build a standalone music player, you can add buttons to control the various functions and mode, or pair it with Arduino or ESP8266 to control it wirelessly.


  • Supports sampling rates 8/11,025/12/16/22.05/24/32/44.1/48 (kHz)

  • 24-bit DAC output

  • 90dB dynamic range

  • 85dB SNR Support

  • Supports FAT16, FAT32 file system

  • Supports up to 32G TF card

  • 3 control modes: I/O control, serial mode and AD button control mode.

  • 30 Level Volume Control

  • Music EQ with 6 levels

What do you need to build a homemade mp3 player?

To build a portable DIY MP3 player you will need:

  • DFPlayer Mini MP3 Player Module

  • An SD card (any card between 100MB-32GB)

  • 1 x 3W speaker (50mm)

  • A PAM8403 3W mini 5V digital amplifier board with a potentiometer (optional)

  • 2 x push buttons to control the MP3 player

  • A micro USB breadboard 5v power module or a TP4056 1A Li-ion battery charging module with a 3.7v 500/1000/2000mah LiPo or 18650 battery to power the device.

  • A 3D printed housing to house all components. You can download this reduced 3D cover for an MP3 player that fits in a 49mm-51mm speaker.

Skills Required

You have some experience with soldering electronic components. If you’ve never soldered a part or used a soldering iron, check out this guide for easy tips on soldering electronics.

However, if you don’t want to solder and want to test or build this temporarily for learning and fun, you can use a breadboard.

Steps to Build a DIY MP3 Player

Follow the steps below to build a homemade MP3 player.

Step 1: Build the Control Panel

To build the control panel to control various functions, such as increasing or decreasing the volume, playing or pausing music, or going to the previous or next track, you need a general circuit board. If you don’t have a general circuit board.

  • Connect the resistors to one of the terminals on all three push buttons as shown in the diagram.

  • Then connect the other terminal of push buttons in parallel with each other and solder it to the GND terminal on DFPlayer.

  • Connect all resistors to the ADKey_1 terminal on DFPlayer.

Knob Function
B1 Play pause
B2 Volume/Back (long press)
B3 Volume+/Next (long press)

Step 2: Connecting speakers

You can now add speakers to the DFPlayer module. The module can drive two 3W 4/8 ohm speakers without any problems. If you are using a 3W speaker, you can connect it directly to the DFPlayer as shown in the following diagram.

You can also install a PAM8403 3W mini 5V digital amplifier board to connect the speaker and control the volume with the volume knob.

However, if you want to connect larger speakers for more sound, you can use a more powerful amplifier module between the DFPlayer and the speakers.

Once all connections are made you can connect a 5V power supply to the female micro USB and then solder the two wires to the DFPlayer as shown in the following diagram.

You can also use a 5mm male/female DC jack to supply 5V power through a 5V adapter.

Step 4: Copy MP3 files to SD card

You can create up to 100 folders and add up to 255 songs to each folder. To add music files, copy the MP3 files to the root folder of the SD card. Don’t create a folder for now.

When you’re done, insert the SD card into the DFPlayer module.

Connect the power and then press the B1 (Play/Pause) or B2/B3 (Previous/Next) button once. It should start playing the MP3 file stored on the SD card.

A long press on B2 decreases the volume. Likewise, a long press on button B3 will increase the volume. A short press on B2 and B3 switches between the previous or next track on the SD card respectively.

Step 5: Arrange the player in a 3D printed case

Once you’ve tested and built a working DIY MP3 player, you can enclose it in a 3D-printed case (as suggested above) or any other enclosure you can find at Thingiverse† You can also design one in Fusion 360.

Step 6: Integrate with Home Assistant

To integrate the DFPlayer or your DIY MP3 player with Home Assistant for smart home automation alerts, you need a NodeMCU or D1 Mini and flash it with Tasmota or ESPHome firmware.

You can use the text to speech converter tool to create mp3 speech alerts or notification alerts and paste those files in the root of your SD card or arrange them in a folder.

Then add automation in Home Assistant. For example, you can choose a device trigger, such as DIY smart ultrasonic water level sensor, choose the MP3 player in action, select payload (MP3 file number) to play when the tank is full or empty or reaches a certain level. You can also build a smart power monitoring device for Home Assistant and play alerts when high power consumption is detected.

Similarly, you add multiple automations for each event in Home Assistant that plays a voice alert through your DIY MP3 player.

Add Bluetooth capability for wireless music

In addition, you can purchase a Bluetooth transmitter, such as KCX_BT_EMITTER, and pair it with the DFPlayer’s DAC output to transmit and play audio to other Bluetooth-enabled audio systems, such as your headphones or Bluetooth soundbar. Similarly, you can side-by-side a KCX BT003 Bluetooth receiver module with DFPlayer to connect your smartphone and wirelessly stream music to your portable DIY MP3 player.

You can even add a microphone to the Bluetooth module to use the DIY MP3 player to receive voice calls.

Still need to buy an MP3 player?

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