A pitch synchronous analysis was carried out over the vowel portions of the CVC utterances /hed/, /had/, and /hod/ and the stressed vowel portions of the sentence, “Few thieves are never sent to the jug,” all recorded by a male speaker. The analysis provided formant frequencies, excitation parameters, and an accurate measurement of each pitch period. There were about 40 periods in each of the vowel portions of the CVC utterances and about 20 in each of the stressed vowel portions of the sentence. Each measured period was replaced by a period obtained by averaging adjacent periods over a symmetric “window.” Window sizes of 2, 4, 8, 16, 32, and 64 periods were selected. The vowel portions were then resynthesized with the new periods but maintaining all other parameters of the original analysis. Subjective evaluation was carried out by means of paired comparison tests between utterances with different window sizes, including the natural utterances. The results indicate that a relatively large amount of averaging is necessary to detect a difference in quality from the natural utterances.