Students' engagement in E-learning applications is considered an important factor for learning. There is an evidence in the literature on the influence of students' engagement on their learning outcomes and achievement. Sound utilization in E-learning applications is expected to influence the students' engagement in such applications. However, research is required to provide more evidences on such influence. The current study adopted the arousal theory, to check whether adding sound's elements (voiceovers, background music and sound effects) to the E-learning applications would improve the students' engagement in such applications. The participants are non-English speaking undergraduate students (N = 272) from a public university in Jordan. They were randomly assigned to the study groups to use one of the eight E-learning applications with different levels of sound's elements to measure the students' engagement in these groups. The study has employed the Analysis of Covariance, ANCOVA, to investigate the proposed hypotheses, and compare the students' engagement among the study groups. The results showed that the sound's elements, especially voiceovers, positively influence the students' engagement, when controlling for students' age, gender, and their prior experience with E-learning applications. These results contribute to theory by confirming the arousal theory in the context of students' engagement in E-learning applications. Practitioners and designers can also be informed, by our results, in designing more engaging educational applications.