Experiments measured the effectiveness and efficiency of audio tape recordings using "time-compressed speech" compared to those using normal recording rates in an audio-tutorial system. The experimental tapes were compressed to 60 percent of the original rate of delivery. Results showed that the rate of speech made no difference in the students' achievement. The time-compressed recording group had a 12.3 percent saving of time as compared to the control group, but this saving is not statistically significant. Little relationship was found between achievement and the personality characteristics of creativity and sociability as measured by the Remote Associations Test and the Thorndike Dimensions of Temperament test. No advantage or disadvantage accrues from using time-compressed recordings in an audio-tutorial system. Results indicate that high rates of speech, up to 210 words a minute, should work well on tapes assuming the speaker is intelligible. (JK)