1. ECE 11 Final Project: Boom Box Design and Implementation By Scott Trocchia ECE 11 Fall 2008 Professor Korman, GTA Yi Jin Presented on 12/16/08

2. The Approach: Divide and Conquer Definition: break large project (seemingly complicated and daunting task) into its constituents (piece by piece) The following slides will explain the circuit through this concept

3. Stage [1] : Initial Low Pass Filter 1 st order Inverting design Establish unity gain Simple illustration of phasor usage Eliminates all noise above 10 kHz

4. Stage [2a]: Decision to make - Treble or Bass? Treble channel 2 nd order high pass filter Reason for order? Unity gain Frequency range of interest: 5360 Hz to 10 kHz

5. Stage [2b]: Decision to make - Treble or Bass? Bass channel 2 nd order low pass filter R  C, C  R Unity gain, again Frequency range of interest: 150 Hz to 7360 Hz

6. Stage [3]: Output Stage Same for treble and bass channels C6 and R8 together represent passive low pass filter Attenuates all frequency <150 Hz C7 makes sure AC voltage passes to speaker

7. Treble’s Voltage Ladder Concept of voltage ladder (+,- polarity) Initial resistor  highest voltage drop Personal preference and guess and check LED resistor?

8. Bass’s Voltage Ladder Concept of voltage ladder (+,- polarity) Personal preference, again LED resistor and why we need it

9. Troubleshooting / Problems / Resolutions Troubleshooting Parts Time issue? Lessons learned and applications