This MATLAB exercise shows the spectral smoothing effects of low quefrency cepstral liftering on the lig magnitude spectrum of a speech signal. This is done by first computing the real cepstrum of a window-weighted frame of speech, and saving the resulting log magnitude spectrum as the baseline (unsmoothed) speech spectrum. A low quefrency lifter is then used to effectively smooth the log magnitude spectrum with the cutoff quefrency varied from a low value of 20 to a high value of 100, in steps of 20 quefrencies. The file '3.14Cepstral Liftering.pdf' provides a User's Guide for this exercise.