In this paper, the results of both normal-hearing, and profoundly hearing-impaired adults, tested with spectrum compressed speech via the modified chirp-z algorithm, with and without visual stimuli, are reported. Ten normal-hearing adult listeners and three profoundly hearing-impaired adult listeners were asked to identify nonsense syllables presented auditorily and bimodally (audition and vision) via video tape in two conditions: lowpass filtered or unprocessed, and spectrum compressed. The lowpass filtered and spectrum com-pressed speech occupies the same spectrum width of 840 Hz; at 900 Hz and above, the attenuation is at least 60 dB. The spectrum compression is performed by means of a modified chirp-z algorithm, and is described in this paper. The testing results are significant and are reported in this paper.