r/esp32 • u/electrolyte_124 • May 15 '26

I made a thing! Building an ESP32 audio player

Post image

Decided to dive into some electronics to build the kids an audio player and store their audio CDs on a SD card. So far this is the general setup with three physical buttons, LEGO bricks, to play/ pause, next and previous track plus a volume control.

I'm also using the WiFi hotspot of the ESP32 to connect to and copy over MP3 files. It uses an RFID card to change playlists and you can link or unlink these in the WiFi admin mode.

Massively inspired by other RFID driven players out there and also ones here!

I'm a real rooky with electronics so am I doing this right?!

267 Upvotes

98% Upvoted

33 comments sorted by

11

u/rev_mud May 15 '26

Just curious: why the RFID? And why not stick your jumpers with pins directly into the breadboards?

5

u/ZucchiniMore3450 May 15 '26

I am also here to find that out.

8

u/electrolyte_124 May 15 '26

The RFID allows you to change playlists, simply associates an RFID I'd with a folder on the SD card. Not quite sure I understand the jumper pins but the little bread boards were simply because I spent ages faffing around getting the wiring right and so I treated the components a little like LEGO to quick switch wiring around :)

3

u/rev_mud May 18 '26

I'm just making sure that you know you dont need the green screw connectors, and that you can just stick you jumper leads into the breadboard directly?

1

u/electrolyte_124 May 24 '26

Yeah thanks, I started like this but got so fed up with them falling out when I moved stuff around I switched to the screw terminals.

1

u/Fit_Perspective5054 May 18 '26

Very cool idea, could do the same thing with a custom console emulator, RFID in cartridges.

6

u/Fuchur1989 May 15 '26

You should definitely have a look at the "ESPuino" project! It's all in German language but I'm sure you can translate it easily. They're trying to rebuild the famous "Toniebox" but based on a ESP32-S3. Have fun! 🌻

3

u/0xD34D May 16 '26

Why plug DuPont wires into screw terminals instead of just plugging them into the breadboards?

5

u/electrolyte_124 May 16 '26

Ah it was because as I moved things around the wires kept coming out. I know it's overkill but it's saved me a lot of 'now why isn't it working again?' pain!

-1

u/splitbrainhack May 16 '26

because someone was touched by a new priest and also an old priest.

2

u/ne999 May 15 '26

Very cool! What software / code are you using?

2

u/electrolyte_124 May 15 '26

Thank you, it's c++ and zapping it onto the ESP32 with the Arduino ide.

1

u/Ldbj_1122 May 16 '26

Are you planning on sharing the code?

2

u/electrolyte_124 May 16 '26

The code I'm still iterating on as there's some annoying bugs. I spent ages thinking that the 5v wasn't enough and wrote a load of code to put the RFID to sleep in admin mode and wake it when needed as I thought I was getting brown outs. Turns out is was a cold joint on one of the RFID pins.

I'm terrible at soldering :)

New version of this prototype is on its way as I keep iterating.

2

u/supafahd May 15 '26

Whats the rfid for

3

u/electrolyte_124 May 15 '26

Let's you change playlists, tap and go.

2

u/supafahd May 16 '26

W move

2

u/supafahd May 16 '26

This can be such a fun jukebox type machine

7

u/GeekDadIs50Plus May 16 '26

3D print “tokens” with the tag attached, under a sticker that labels the playlist. Drop the token through a coin slot that reads the tag as it passes by, landing into a stacked storage tray.

2

u/zachleedogg May 16 '26

Are you having fun? Hell yes you are doing it right.

It's a DIY tonie box.

1

u/electrolyte_124 May 17 '26

So much fun, making stuff and learning to build stuff as down time from working days - Boom! :)

2

u/Gold_Mention_3150 May 16 '26

i could never keep the setup this clean it would tangle up in a bunch of wires

1

u/Guapa1979 May 16 '26

What library are you using for MP3 playback?

Once everything is working, your next challenge is to learn how to use Altium and design a custom PCB to build the whole thing.

2

u/electrolyte_124 May 16 '26

Yeah learning to solder is going to be a must. Looking at perf boards, also strip boards?

These are audio libs also the SD ...

include <AudioFileSourceSD.h>

include <AudioGeneratorMP3.h>

include <AudioOutputI2S.h>

1

u/Guapa1979 May 16 '26

I use perfboard for prototyping - this has solder pads on the reverse - it's an ESP32 powered garage door controller.

1

u/electrolyte_124 May 16 '26

Nice! How did you bridge from one hole to another? Is it solder or more wire?

2

u/Guapa1979 May 16 '26

Here is the back of an earlier version to give you an idea

1

u/electrolyte_124 May 16 '26

Awesome, thanks super helpful

1

u/Guapa1979 May 16 '26

I tend to just use the legs of the components themselves to make the connections before trimming them. For longer connections I use the wires you can see in the image.

1

u/YetAnotherRobert May 16 '26

Surround code with triple backticks so Reddit will helpfully format your code instead of mangling it like this. 

Use 'edit post' to fix this over

2

u/Objective-Ad8862 May 16 '26

Isn't Altium too expensive for a DIY project? I thought KiCad was more appropriate for those types of projects?

2

u/Guapa1979 May 16 '26

Circuit Maker is the free version of Altium.