Executive Summary

Davidsen, LLC is a family run company that is looking into developing a noisemaker that can be used at all outdoor sporting events. The objective of the noisemaker is to emulate the sound of a bare handclap. Davidsen, LLC has developed three different prototypes but needed further testing to compare the prototypes to a bare human handclap and existing noisemakers.

A formatted test plan was developed to analyze the acoustics of a person’s handclap. A microphone with a test stand and a program entitled SigLab was used to study the sounds comprised in a handclap.  The key points the team will investigate are the sound pressure level versus the frequency of a handclap as well as existing noisemakers. The testing was performed at the Penn State Anechoic Chamber located in the Hammond Building. This chamber was used to eliminate any uncontrollable noise, therefore allowing the microphone only to detect generated noise from the handclap, prototypes and an existing noisemaker, Cheer Stix.

Testing of 40 subjects ranging from the ages of 18 through 75 years were tested since this is the dominating age group of most sporting audiences. Each subject were located a distance of one meter away from the microphone, and asked to clap as loudly as possible 15 times. All 40 subjects were tested clapping with their bare hands as well as with the noisemakers that were provided to them.

An analysis of the data was then performed upon completion of testing. The peaks of each subject's test was collected from the SigLab data graphs and comprised into an Excel spreadsheet. An ANOVA statistical test was run using a SPSS program on the data. The ANOVA test allowed the team to determine if the noisemakers were producing an equal sound pressure level as a handclap, and if there was a difference to determine how significant the difference is.

The ANOVA test concluded that the prototypes are not equal in sound pressure level to a handclap and that there is not a significant difference to a handclap. The Cheer Stix has a significantly higher difference than that to a handclap according to the results of the ANOVA test. It was determined that the prototypes produce a lower sound than a bare handclap and that the Cheer Stix produce a higher sound than both a handclap and the prototypes. 

Problem Statement

An acoustical definition of a handclap is needed to further test and analyze existing noisemakers and the prototypes and compare them to a handclap.

The Fan Hands Teams objectives were to design a test plan to characterize the generated noise of a handclap using the SigLab program, recruit and test subjects ranging from the ages of 18 to 75 years with the prototypes and noisemaker and compare results to a handclap, and to provide recommendations to Davidsen, LLC based on results for improving the prototype.

Testing

The Fan Hands team developed a formatted Test Plan to allow for the testing of each subject to be conducted the same. Testing was done using the SigLab program and a microphone. The Test Plan included procedures for the set up of the equipment, instructions on running the SigLab program, instructions for testing each subject and procedures for saving and calculating the results. Each subject performed the tests of the noisemakers, prototype and handclap in a different order given in the test matrix.

Results

An ANOVA statistical test was preformed on the data to determine if the noisemaker and prototype produced an equal sound to that of a handclap. This was done by taking the peaks of the handclap, prototype and noisemaker of each subject and placed in an Excel spreadsheet. The SPSS program was used to run the ANOVA test. The test concluded that the prototypes are producing less sound than a handclap and the Cheer Stix (noisemaker) is producing a higher sound than the handclap. The graph concludes the data obtained by through the ANOVA test is correct.

Graph 1: Comparison of Sound Pressure Levels

 

Conclusions and Recommendations

The Fan Hands team feels that the best prototype that comes close to the sound pressure level of a handclap is prototype C. Prototype C is the only one out of the three prototypes that produces a peak sound of 84 dB(SPL) which is very close and less than the peak sound of the handclap at 86 dB(SPL). The team feels that Davidsen, LLC should continue production of prototype C and terminate production of the other two prototypes.

The following is a list of suggestion for Davidsen, LLC regarding the prototypes:

  • Provide a Velcro strap that is adjustable with the use of one hand.
    • Consider using a strap with a loop to easily allow for adjustment (EX: straps found portable CD player)
  • Attach a backing to the prototype to prevent it from digging into hands.
    • This would equally distribute the force applied to the hands when clapping the prototypes together.
Team Members:   Brad Piehel          Jim Nguyen           Gerald Restubog         Mark Christman          Debra Wolfe