Vibrational and Acoustical Characteristics of Ear Pinna Simulators That Differ in Hardness

Round 1

Reviewer 1 Report

This is an interesting paper concerning the characteristics of ear pinna simulators at different hardness levels. It presents data about vibration acceleration level and sound pressure level recordings at various settings, which are useful for designing cartilage-conduction hearing aids and ear simulators. The paper is well written and easy to follow.

I have one specific comment: please describe in more detail on how the measurements from human ears were actually conducted if they are from other studies. Also, the variability of the data from the ear simulators are generally larger with more small peaks. Please explain.

Some minor changes:

L39: "cartilage is stimulated" to "the cartilage is stimulated"

L212: "from ears of participants" to "from the ears of participants"

Please check other errors in grammar and word usages.

Author Response

Please see the attachment.

Reviewer 2 Report

The submitted paper is really a good one, but at present stage it needs some improving: English should be corrected by a mother tongue revision and the references are too short. This last part can be expanded by improving background information in the  introduction.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Summary

The authors describe a study that aimed to develop a simulator for cartilage sound conduction. Measurements were obtained for vibrations at the pinna, and sound in the external auditory canal, using pinna simulators carrying in hardness, including the existing Head and Torso simulator (HATS). Measurements were compared to those obtained using a human ear. The simulated levels for vibration acceleration and sound pressure approached the measurements obtained for human ears for pinna simulators similar in hardness to human cartilage. The findings suggest that the pinna simulator of the HATS is not hard enough to accurately simulate the vibration in human aural cartilage.

 

General comments

The paper is generally well-written and the findings will be of interest to readers of Audiology Research. The methods appear sound, as do the conclusions drawn from the data. I have only a few suggestions that the authors may wish to consider.

 

Line 42: “Although cartilage conduction hearing aids can decrease hearing thresholds, especially of users with aural atresia, otorrhea and microtia…”

            Please provide citations to support this text.

 

Line 72: “From durometer measurements, the hardness of the various silicon rubbers was classified into five classes: A0, A5, A10, A20, and A40.”

            Suggest clarifying why these hardnesses were chosen for testing.

 

Figure 2: “mm” is partially obscured in the left panel. Please correct.

 

Line 113: “The sound recordings were performed in background noise of less than 30 dB.”

            Was the testing room anechoic?

 

Discussion: Some mention of any possible limitations to the study might help strengthen this section.

 

Line 179: “pina.” Typo.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf