Homemade Speaker Competition

Background

Design teams of three students per team will build and test a simple speaker. The following information will provide further details. The only provided materials are AWG 30 magnet wire, a 0.5” x 0.25” Neodymium magnet, and plastic cups. A mono audio jack (1/8”) is available in the classroom for testing.

The Task

The design challenge of the speaker competition is for each design team to construct a single best-possible speaker to be evaluated on the merits of performance (45 pts), write-up (45 pts), and aesthetics (10 pts) by a somewhat independent panel of judges. The design activity will last two weeks. This is a formal lab report and will be a substantial portion of your grade for the third quarter.

Week 1

Your group should make a plan for evaluating speaker designs. Speaker performance will vary dramatically based on the materials chosen, the shape and construction of the cone and enclosure. A wise decision would be to plan for a variety of prototype designs to be constructed during the first week so that they can be evaluated and a candidate group design chosen. It will be up to your design group to self organize and determine what approach to this competition you wish to take.

Week 2

Construct and optimize your final speaker configuration, making note of step-by-step procedural instructions and diagrams. Write up design report.

Resources

1. How Speakers Work: http://electronics.howstuffworks.com/speaker1.htm

2. Cup Homemade Speaker Instructions: http://josepino.com/circuits/?howto-speaker.jpc

3. Plate Homemade Speaker Instructions: http://josepino.com/other_projects/?homemade-hifi-speaker.jpc

4. Homemade Speaker Video: http://www.metacafe.com/watch/719200/homemade_speakers/

5. Speaker Background Information:

a. http://www.ece.tufts.edu/es/3/SpeakerProject_2_DesignBackground.pdf

b. http://www.ece.tufts.edu/es/3/SpeakerProject_3_SpeakerOperation.pdf

c. http://www.ece.tufts.edu/es/3/SpeakerProject_4_HowSpeakersWork.pdf

6. Similar Speaker Project and Directions from EE Department at Southern Methodist University: http://lyle.smu.edu/ee/1382/Speaker%20Lab.doc

Design and Report

Speakers will be evaluated based on their loudness, audio quality, and style. The accompanying web links are designed to help educate you on speaker design fundamentals and perhaps inspire you to come up with a particularly innovative design. You are welcome to use the instruments and tools in the classroom for construction and pre-testing of your speaker. The use of manufactured speakers or speaker components is not allowed.

Groups may consist of no more than three students. You must submit individually a report of five pages in length which should include sketches of your design as well as a discussion about the theory behind your design and any difficulties you may have encountered. Your entire lab report must be your own.

If members of your design team are not contributing to the design activity, you may choose to outline the contributions of every team member in an appendix to make the graders aware of the lack of contribution.

The lab report format should be as follows:

I. Title Page

II. Introduction

III. Background & Theory of Operation

IV. Materials List and Cost Estimate

V. Procedure

VI. Data & Drawings

VII. Analysis & Discussion

VIII. Conclusions

Assessment
Homemade Speaker Project
Performance		Max	Score
	Speaker Built	9
	Sound is Heard	9
	Sound is Distinguishable	9
	Words Are Distinguishable	9
	Loudness	9
Write-Up
	Title Page Included	5
	Introduction in Paragraph Form	5
	Background and Theory Described (w/diagrams)	5
	Materials List and Cost Estimate Included	5
	Procedure Complete	5
	Data Presented, Diagrams / Pictures Shown	5
	Analysis Describes Designs Considered	5
	Analysis Explains Why Final Design Chosen	5
	Conclusions Describe Improvement Opportunities	5
Aesthetics
	Neatness	5
	Style	5
Total		100