Purpose: The purpose of this letter is to refute the comments written by Smits, Goverts, and Versfeld (2018).
Method: Refutations to each issue including the fixed mathematical relationship between dynamic range (DR) and a fitting constant (Q value), deviating results for small DRs, and determination of Speech Intelligibility Index (SII) model parameters are described.
Results: Although Smits et al. (2018) correctly identified several issues, those comments do not diminish the results of the original article (Jin, Kates, & Arehart, 2017) in providing new insights for the SII.
Conclusions: Jin et al. (2017) clearly provided the impact of languages and DR on the SII, which was the main result of the study.