This book provides a clear and accessible explanation of acoustics, focusing on how wind instruments produce sound. It connects the physical principles of musical instruments with science and mathematics, encouraging readers to think scientifically about familiar phenomena in music. While stringed and percussion instruments allow us to see and feel vibrations, making sound production intuitive, wind instruments rely on invisible air vibrations. Understanding these requires knowledge of acoustics, which extends beyond high school physics into university-level science and engineering. However, this book aims to explain these concepts in a way that is understandable even to those without a technical background. To accommodate different levels of expertise, the book is divided into two parts. The first, Reading Part , uses only text and diagrams to explain acoustic principles, minimizing mathematical formulas. It targets a broad audience, from middle and high school brass band members to adult wind instrument players. Basic information is easily found online, and simple definitions (e.g., "pitch corresponds to frequency") are intentionally omitted to maintain focus and clarity. The second part, the Technical Part , presents the same topics in a more technical manner, incorporating mathematical formulas and scientific reasoning. Each chapter in the Technical Part corresponds directly to one in the Reading Part , allowing readers to gain a foundational understanding before delving into more complex material. This structure - combining general and technical content in one volume - is relatively rare. Readers are encouraged to explore the sections that suit their interests and needs. The goal is to show how school-level science and math are directly related to the physics of musical instruments. In particular, the book aims to inspire middle and high school readers to approach music and instruments from a scientific perspective. The hope is that readers of all backgrounds will find value in the content and, over time, feel motivated to explore the technical Technical Part as their understanding deepens.