Noise Source Visualization Using a Digital Voice Recorder and Low-Cost Sensors

Area of Science:

• Acoustics
• Signal Processing
• Instrumentation

Background:

• Optimal noise control necessitates accurate sound visualization of noise sources.
• Conventional noise measurement systems are often expensive, bulky, and lack portability.
• Consumer-grade digital voice recorders offer a low-cost, portable alternative but require modification for accurate measurements.

Purpose of the Study:

• To develop a low-cost, compact sound visualization system for identifying noise sources.
• To assess the feasibility of using modified digital voice recorders for noise measurement.
• To verify the system's accuracy with diverse noise sources.

Main Methods:

• External microphones were connected to a digital voice recorder.
• Recorded audio input was processed for noise visualization.
• The system was tested on an enclosed loudspeaker and a small air compressor.

Main Results:

• The developed system achieved reasonable accuracy in visualizing two distinct noise sources.
• Effective noise visualization was demonstrated over a wide frequency range.
• The system proved to be both affordable and compact.

Conclusions:

• A low-cost, portable sound visualization system can be effectively implemented using digital voice recorders and external microphones.
• This system provides a viable solution for noise visualization in various applications, including education.
• The findings support the use of consumer electronics for specialized measurement tasks with appropriate modifications.