Guitar Effects Processor Using DSP

Presentation Transcript



Guitar Effects Processor Using DSP Alex Czubak Gorav Raheja Advisor: Dr. Thomas L. Stewart

Problems Need for continuous impacts era for live exhibitions and recording Effects pedals exist, yet better utilized for presets

Overview Overall Project GUI Interface Filter Design Results and Conclusions

Overview Overall Project GUI Interface Filter Design Results and Conclusions

Overall Project Guitar flag to DSP Passes through channels User controls channels through GUI Signal yields to speaker

Project Specs 8 Effects channels in both parallel and arrangement Sampling Rate = 48,000 specimens/sec GUI controls impacts channels Real-time preparing at a speed at most 1/inspecting rate

Canceled Original Spec Noise Filter Eliminates 60-Hz murmur from single-loop pickups Sampling rate made plan troublesome Pole and zero for all intents and purposes cover Multiband approach considered Z-Transform Function if examining rate = 48000

Canceled: Noise Filter FFT of flag shows pointlessness of channel FFT of Strat: A-110 Hz Noise Component of Strat Signal

Guitars Used Squier Stratocaster 3 Single-curl pickups 5-way selector switch Squier Telecaster Custom 2 Humbucker pickups 3-Way Selector Switch

Amplifiers Used Fender Frontman 15R Guitar Amplifier External Reverberation Potentiometer set to 0 so planned Reverberation impacts can be tried Distortion station, overlooked to test outlined channel Output: 15 watts into 8 ohms

DSP Board Used Spectrum Digital TMS320C6713 DSK DSP Chip: Texas Instruments C6713 @ 225 MHz 16 MB SDRAM 512 KB Flash Memory AIC23 Stereo Codec permitting 8-kHz to 96-kHz inspecting rate A/D and D/A Converters just handle 2 Volt abundancy max

Programs Used MATLAB and Simulink Quick change of sound for testing Graphical displaying of channels GUI outline joins with models Auto C-code era for DSP load up Code Composer 3.1 Programs code to load up Only approach to interface with load up

Overview Overall Project GUI Interface Filter Design Results and Conclusions

GUI Allows client to choose and control impacts Interface straightforward and simple to utilize

GUI Software Design

GUI Testing Initial cases to comprehend GUI in MATLAB Uploading/playing wave documents Tying GUI through Simulink models Connecting GUI through Simulink to DSP load up for "constant" usage

Tying GUI and simulink

Sample testing (no impacts)

Sample test (with impacts utilized)

Overview Recap of Overall Project GUI Interface Filter Design Results and Conclusions

Filter Design: Overview 8 client modifiable channels Distortion Volume Envelope Octaver Flanger Phase Shifter Chorus Delay/Echo Reverb Control Signal: A @ 110 Hz

Filter Design: Distortion Boosts and clasps flag Gain values from 1 to 50 Saturation at - 0.5 and +0.5 Telecaster – A 5 th Chord Simulink Distortion Model

Filter Design: Volume Envelope Signal assault is disposed of Violin-sort sound Signal bit by bit approachs full esteem Does so for each culled note

Filter Design: Octaver Octave Down Halves recurrence of flag Output at same speed as information A @ 55 Hz from MATLAB Code

Filter Design: Flanger Signal is part Passed through factor time defer Controlled by sine wave at <= 1 Hz Maximum deferral = 10 ms Flanged "NBC" Simulink Model of Flanger Effect Filter

Filter Design: Phase Shifter Similar to Flanger, yet: All-pass channel rather than simply postpone Creates non-directly separated indents 2 channels = 1 score 8 channels for 4 indents

Filter Design: Chorus Similar to Flanger, however: 4 parts rather than 1 Creates multi-guitar sound User chooses what number of are on Sine waves keep running at 3 Hz and 6 Hz

Filter Design: Chorus Simulink Model of Chorus

Filter Design: Delay/Echo Signal is part Fixed defer dictated by client Audio Test of Delay/Echo Delay/Echo Model

Filter Design: Reverb Delay-based channel Attenuated criticism rots sound Delay decides length of rot Reverb Test Filter

Overview Recap of Overall Project GUI Interface Filter Design Results and Conclusions

Results MATLAB 5 of 8 impacts completely utilitarian Octaver moderates flag Volume Envelope just for first note Phase Shifter not including any impact

Results GUI Connection to Simulink less demanding versus coordinate hard-coding No ongoing application, yet Simulink association is the progression before that

Results Real-Time 3 of 8 impacts work legitimately 3 have variable-time postpone issue "Popping" Happens if impact is available in framework 2 haven't been concluded in Simulink

Results Real-time demo

Conclusions Effects Simulink and Code Composer permit brisk ongoing advancement Real-time variable-time defer a confused matter Embedded M-document piece not a basic answer for Volume Envelope

Conclusions GUI Significant expectation to absorb information at initially Need to characterize all factors from workspace if utilized No data on interfacing GUI to DSP load up Simulation environment exhibited great usefulness

Conclusions Future Ideas Effects Improved variable-time defer calculation for DSP Board Add more impacts to framework Wah-wah Talk-Box Add pedal usefulness to choose consequences for the fly USB or PC Card association with tablet for movability GUI Allow constant execution More factor control for more dynamic impacts

And so… We could cut the house down!!!

Questions?