There have been constant demands on effective compression schemes for speech signals in both clinical and commercial applications. The effects of these strategies on word recognition tasks appeared to be dependent on the implemented algorithm of the compression, the features of the speech, and the properties of the auditory processing system. It, therefore, is necessary to evaluate the effects of compression schemes on individual languages. However, the related standard data for Korean words were limited in number and this might lead to the inadequate application of the particular compression scheme. In this study, the properties of a typical time-frequency altered compression scheme were analyzed for Korean quintet monosyllabic digit sets in normal hearing young adults. The representative basic compression scheme was based on the time-frequency altered compression preserving no particular traits (PNT) in spectro-temporal domain. Twenty normal hearing young adult subjects (10 males, 10 females) were evaluated for this scheme with the predetermined compression ratios of 1 (no compression), 0.71, 0.5, 0.33, and 0.25. These randomized quintet stimuli were presented to the subjects through acoustically calibrated insert earphones in a custom-made auditory workstation. The results showed rapid deterioration of performance for the corresponding high compression ratios. No statistically significant differences were observed for male and female subjects in the outcomes of the five compression ratios (p > 0.05). In the response profile of PNT, the estimated compression ratio for 50% performance was about 0.44. In summary, a typical time-frequency altered compression scheme (PNT) showed a poor performance near the point where the amount of compression was doubled. This, however, may not indicate the same results for optimized time-frequency features. Thus, profiles of individual compression schemes need to be clinically evaluated and compared for their efficiency and effectiveness.