E 232 Final Project

Andrew Finateri, Michael Conrad, Stefan Major

Finding The Frequencies 1

61.8 Hz, 740 Hz, 9397 Hz

High Pass Filter 2

Cutoff frequency of 9.2k Hz

2nd order Butterworth

Had low attenuation

2nd order filter so it was less complex to build

The minimum sampling rate needed to prevent aliasing is 18,794 Hz

Low Pass Filter 3

Cutoff frequency of 70 Hz

2nd order Butterworth

Had low attenuation

2nd order filter so it was less complex to build

Matlab 4

This is the code we used in Matlab. We attached the audio and the simscape file inside the code and then ran it to get our desired output.

Simscape 5

We first started our simscape design by creating this to get our input voltage. This included a solver configuration, a converter, a Workspace block, an electrical reference, and a controlled voltage source.

Simscape Cont. 6

The next step in the process of creating our design was to add either a non inverting or inverting amplifier. We chose a non inverting one as shown here. This included adding multiple resistors and an Op-amp. The resisters were 1 kOhm and 10 kOhms.

Simscape Cont. 7

The next step was adding High Pass and Low Pass filters stemming from our amplifier. After we had to add a buffer to the end of each one. This was to prevent loading error. We had to add some capacitors along with some more resistors and op-amps.

Simscape Cont. 8

The final step was to add our load resistors with the correct resistances for the LO and HI part of the speaker. We then had to connect another workspace block for each with a converter as well. We finished by inputting all the correct measurements for each resistor and capacitor that we got originally.

Simscape Problem Encountered 9

The main problem we encountered throughout the simscape process was realizing after we created the simscape, when making our physical circuit, that the values we used for our resistors and capacitors were not available to use in class. We had to switch the values to resistor and capacitor values we could actually use.

Physical Implementation 10

Overcoming Challenges:

• Odd resistor values, had to make series of smaller sized resistor (Didn't always add up exactly)
• Troubleshooting circuit, once built, did not work on first try
• Finding useable wires to connect series of resistors, capacitors, op amps and other component’s. (most specifical aux cord to circuit)

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Youtube Links 11

• Low pass Filter
• High pass Filter
• Both

Concluding Remarks…

The output signal in the digital filter was much more consistent since it was a simulation where their was max efficiency and no room for errors with wire connections. It was also lot easier to create in matlab compared to the physical version since there was no need to add up resistor values, and triple check connections and inputs.