In this paper, we prepared tri-syllable articulation testing sound sources which have been changed into four types of speech rates, and conducted hearing tests in real sound fields. Thereby, we compared and examined these relations with the response properties of echo diagrams in the sound fields. Further, we analyzed the frequency of each speech rate in conversation, and weighted the tri-syllable articulation test results for each of four types of speech rates in consideration of frequency. Finally, through the corresponding relations between the results of weighted tri-syllable articulation tests and those of speech intelligibility tests in conversation, we proved the effectiveness of the evaluation method of tri-syllable articulation in consideration of speech rate in conversation.
