Part A
Click on one of the phonemes below to view it’s acoustic features.
Or click below to see 3D plots of Power Spectral Density vs Frequency vs Time.
For a downloadable zip file of the sounds, please click here. The differences between the major phonemic categories are seen in the above figures, and the results are as expected. Vowels exhibit highly periodic spectrograms, while unvoiced phonemes were largely characterized by their noisy spectrograms.
Part B
An ideal telephone channel was created using overlap and add frequency domain techniques with zero padding. The channel is shown below.
Both a spoken sentence and a sung sentence were passed through the ideal filter. The plots of their magnitude spectrums are below. If interested, check out the original song and the filtered song.
Also, the phonemes from before were run through this ideal filter. This had a particular effect on the voiced and unvoiced fricatives, since the filter removed aspects that previously distinguished the two.