Yamaha Acoustic Engineering Program - 4. Sound Intensity and Loudness: Levels and Calculations

Course overview

In this course, you’ll build a practical, engineer-friendly understanding of “level” in acoustics—connecting sound pressure, sound intensity, and perceived loudness. You’ll learn how reference values define what a decibel number means, how human hearing changes with frequency, and how to calculate and compare levels correctly in real-world audio scenarios.

What You Will Learn

  • How sound pressure level (SPL) is defined using a fixed reference, and why reference conditions matter when comparing dB values
  • The definition of sound intensity and sound intensity level, and how sound pressure, SPL, and intensity relate
  • How frequency affects perceived loudness (equal-loudness contours), and why weighting filters (such as A-weighting) are used in measurements
  • How to perform correct decibel calculations, including combining sound sources and using practical approximation methods
  • Common decibel scales used in audio (e.g., dBW, dBm, dBu, dBV, dBFS) and guidance on notation in formal documents
  • CTS RUs: 0.75, CTS-I RUs: 0, CTS-D RUs: 0, ANP RUs: 0
  • Study time: 45 minutes
  • Exams: Multiple choice
  • English

Earn AVIXA RU Credits

After receiving your Certificate of Completion, tap the logo below to visit the AVIXA site. Then, upload your Certificate to receive RU credits.

AVIXA logo: Jump to the AVIXA website.

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