Arduino – Harry Potter Music Box

Concept

For this project, I decided to create a mini music pad that can play the Harry Potter theme. The idea came from a small Harry Potter music box that I was gifted when I was younger, since I have always loved Harry Potter and I am a big fan. I also play the piano, so I wanted to design something that felt similar to an instrument and could simulate specific notes like a simplified keyboard.

Process

For the hardware, I used four colored buttons, a potentiometer, and a buzzer to produce sound. I connected each button to a digital pin, the potentiometer to 5V, GND, and analog pin A0, and the buzzer to another digital pin. All components were connected to ground appropriately.

For the coding part, it was a bit challenging at first to find the right notes. I experimented with a basic Arduino buzzer note library and helped myself with Chat GPT to adjust different frequencies until they sounded closer to the melody I wanted. Since the Harry Potter theme has more than four notes, I used the potentiometer as an analog input to change the pitch of the notes. This allowed me to expand the range of sounds using only four buttons. Although it is not perfectly accurate, the result is still very recognizable and captures the essence of the original theme.

// ==============================
// MINI MUSIC PAD - HARRY POTTER SONG
// ==============================


// BUTTON PINS 
int b1 = 2; // E
int b2 = 3; // G
int b3 = 4; // B
int b4 = 5; // C 

// BUZZER 
int buzzer = 8;

// POTENTIOMETER 
int pot = A0;


// NOTES 
#define E4 329
#define G4 392
#define B4 494
#define C5 510


// ==============================
// SETUP
// ==============================
void setup() {

  pinMode(b1, INPUT_PULLUP);
  pinMode(b2, INPUT_PULLUP);
  pinMode(b3, INPUT_PULLUP);
  pinMode(b4, INPUT_PULLUP);

  pinMode(buzzer, OUTPUT);
}


// ==============================
// LOOP
// ==============================
void loop() {

  int potValue = analogRead(pot);

  // HIGH / LOW pitch mode
  bool highPitch = potValue > 512;

  float multiplier;

  if (highPitch) {
    multiplier = 1.3; // slightly higher pitch
  } else {
    multiplier = 0.85; // slightly lower pitch
  }

  if (digitalRead(b1) == LOW) {
    play(E4, multiplier);
  }

  else if (digitalRead(b2) == LOW) {
    play(G4, multiplier);
  }

  else if (digitalRead(b3) == LOW) {
    play(B4, multiplier);
  }

  else if (digitalRead(b4) == LOW) {
    play(C5, multiplier);
  }

  else {
    noTone(buzzer);
  }
}


// ==============================
// FUNCTION
// ==============================
void play(int note, float mult) {
  tone(buzzer, note * mult);
}

Thing That I’m Proud Of

One part of the project I am especially proud of is how I used the potentiometer to control the pitch. This idea allowed me to overcome the limitation of having only four buttons. Initially, I tried pressing multiple buttons at once to create different sounds, but it did not work as expected. Then I realized I could use the potentiometer to dynamically change the pitch, which was a much more effective solution. I am also proud of the overall design of my mini music pad, as it is intuitive to use and much cleaner than my earlier versions, where the wires were more disorganized.

// HIGH / LOW pitch mode
  bool highPitch = potValue > 512;

  float multiplier;

  if (highPitch) {
    multiplier = 1.3; // slightly higher pitch
  } else {
    multiplier = 0.85; // slightly lower pitch
  }

Overall Reflection

Overall, I really enjoyed this project. It allowed me to combine something personal, like my love for Harry Potter and music, with technical skills such as coding and circuit design. The process involved a lot of experimentation and problem-solving, especially when trying to match the melody. This project also made me feel nostalgic, since the song reminds me of my childhood. I am very happy with the final result and how I was able to turn a simple Arduino setup into an interactive musical experience.

SCHEMATIC

VIDEO

Reading Reflections

Reading A Brief Rant on the Future of Interaction Design and the Response honestly changed the way I see technology in a way I did not expect at all. I agree with the author, but what surprised me the most is that I had never even realized this was a problem in the first place. It is not that our devices are bad, but more that they are limiting us from using our full potential, especially when it comes to how we physically interact with the world.

One thing that really stuck with me was when I started thinking about the idea of using devices with your eyes closed. I asked myself what I could actually do like that, and the only thing I could come up with was typing on my laptop keyboard. And then I realized that typing is one of the only truly tactile interactions we still have, and it is not even part of the screen itself. Everything else, especially touchscreens, feels like just sliding your finger on glass with almost no physical feedback. The reading describes this as “Pictures Under Glass,” and I think that is such a perfect way to put it, because it really does feel disconnected from what you are doing.

It also made me think about why we keep simplifying technology more and more. At first it seems like progress, because everything becomes easier and more accessible, but at the same time, it feels like we are reducing the way we interact with the world to something very basic, almost like we are being treated as toddlers. And that idea really stayed with me, because I had never questioned it before. I never thought that maybe we actually deserve more complex and richer ways of interacting, instead of everything being reduced to tapping and swiping.

I also kept thinking about the comparison between the real world and digital interfaces. In real life, our hands are constantly feeling, adjusting, reacting. The reading gives examples like holding a book or a glass and understanding things like weight and position without even thinking about it. That made me realize how much information we are losing when everything becomes flat and two dimensional. It made me wonder if we are actually moving forward or backward by making everything more and more screen based.

At the same time, I thought about things like movie theaters. It took so long for us to even be able to record and display images, but now we have 3D, 4D, and experiences where you can feel water or heat from what is happening on screen. That feels like a step toward engaging more of our senses. But then I started thinking, what if we did not need glasses to see in 3D, or what if devices could actually communicate through touch in a more real way? Something closer to real life, like materials that change shape or give feedback. That is kind of what the author is pushing for with the idea of a “dynamic medium that we can see, feel, and manipulate.”

At some point, though, I also started questioning how far this can really go. If we keep trying to make technology more and more like real life, are we just trying to recreate reality itself? Because the real world is already the most advanced “interface” we have. So it made me think about where the limit is, and whether the goal should be to replicate reality or to create something entirely new.

Overall, this reading really opened my mind. It made me realize that interaction design is not just about making things look nice or easy to use, but about deeply understanding human capabilities and not ignoring them. I had never questioned touchscreens before, but now I cannot stop thinking about how much more is possible and how much we might be missing out on by staying with what we have.