Just because the sound pressure levels remained basically the same or are higher does not mean it is worse or unchanged. Remember quieter (less loudness) is not always better and the same goes for dBA. It was important to verify whether the engineering changes would be acceptable to the user.

This was accomplished in 3 parts.

1. Analyzing the data using a “hearing model”

2. Perform jury testing

3. Development of a specification that included this type of sound attribute

The hearing model analysis, combined with our aurally equivalent analysis techniques, helped verify what users were hearing and complaining about as shown below:

 

 

 

 

 

 

 

 

 

 

 

 

The final part of the project was developing the specification for this type of product. The specification included the analysis metrics obtained from the psychoacoustic analysis combined with the jury testing to be used as a sound quality prediction, of user acceptance, and engineering guide for future products.

Final Proof