1. What is Distance Attenuation?

Distance attenuation describes how sound intensity decreases as it travels through space. The decibel decrease follows an inverse square law relationship, where sound level decreases by 6 dB for each doubling of distance from the source.

2. How Does the Calculator Work?

The calculator uses the distance attenuation formula:

Where:

• \( \Delta L \) — Decibel decrease (dB)
• \( r_1 \) — Initial distance from source (meters)
• \( r_2 \) — Final distance from source (meters)

Explanation: This formula calculates the sound level difference between two distances from a point source in a free field environment.

3. Importance of Distance Attenuation

Details: Understanding distance attenuation is crucial for audio engineering, noise control, acoustic design, and predicting how sound levels change in various environments.

4. Using the Calculator

Tips: Enter both distances in meters. Values must be positive numbers. The calculator will determine the decibel difference between the two distances.

5. Frequently Asked Questions (FAQ)

Q1: Why does sound decrease with distance?
A: Sound energy spreads out over a larger area as it travels from the source, resulting in decreased intensity at greater distances.

Q2: Is the attenuation always 6 dB per distance doubling?
A: Yes, for a point source in free field conditions, sound level decreases by approximately 6 dB each time the distance doubles.

Q3: Does this apply to all environments?
A: This formula applies best to outdoor environments or anechoic chambers. Indoors, reflections and reverberation affect the actual attenuation.

Q4: What if the distances are very close to the source?
A: The formula works for all distances, but very near the source, the sound field may not be fully developed as a spherical wave.

Q5: Can this be used for line sources?
A: No, line sources follow different attenuation patterns (approximately 3 dB per distance doubling).