1. JEG AUDIO Justin McDowell Edward Jones Greg Fagula 525.742 – SoC FPGA Design Laboratory (Final Project)

2. Table of Contents Project Description Requirement System Block Diagram Work Delegation Functional Block Diagrams Audio Codec Display controller Microprocessor / DDR2 Interface Sound Modulation Interface Demonstration

3. Requirements User interface Upon startup with microphone and speakers attached, a user can select these options: Record Voice sample (20 seconds each sample) Upon key press, user may record a 20 second sample. Sample Modification User can select which sample to play back (limit 10 recordings. TFT Display to increment / decrement sample to play back) Modulate selected recorded sample After Sample selection, user can choose which kind of modulation to apply. Options include: Echo, Chorus, Robotic, Overdrive, and RAW playback Continuous Playback User may request apply modulation scheme in real time to play out. (Sample recording is disabled with this choice) With this selection, user can request to stream voice samples over Ethernet for data analysis (FFT plot of selected modulation)

4. System Block Diagram

5. Sound Modulation Interface Chorus Effect Implementation Achieved by adding a slightly delayed version of the original signal (~10-20ms) back to the main signal and mixing a low frequency oscillator (LFO) to the modulated signal.

6. Sound Modulation Interface cont’d Chorus Block Diagram

7. Sound Modulation Interface cont’d Chorus Wave Form

8. Sound Modulation Interface cont’d Echo Block Diagram

9. Sound Modulation Interface cont’d Overdrive (Distortion) Implementation This effect is created by clipping the waveform of the output to compress the peaks of the voice’s wave (For our system, we are hard clipping)

10. Sound Modulation Interface cont’d Overdrive (Distortion) Block Diagram

11. Sound Modulation Interface cont’d Overdrive (Distortion) Wave Form

12. Sound Modulation Interface cont’d Robotic Sound Implementation Effect achieved by taking the original waveform and mixing (multiplying ) it with a LFO between ~100 -> 1000 Hz

13. Sound Modulation Interface cont’d Robotic Sound Block Diagram

14. Sound Modulation Interface cont’d Robotic Sound Wave Form

15. Demonstration