The present study is titled:
The effect of background noise on the audibility of tones in online studies

This research is under the responsibility of the Centre National de la Recherche Scientifique (CNRS), a public research organism in France. The principal investigator is Dr. Daniel Pressnitzer, Laboratoire des Systemes Perceptifs, CNRS & Ecole normale superieure, 29 rue d'Ulm, 75005 Paris, France. This research has obtained the ethical approval of the CEEI Inserm, approval 21-858.

Goal of the study:The aim of our study is to investigate the use of a Threshold-Equalizing Noise in online auditory studies to help equalize the audibility across the frequency spectrum, despite the potential differences in experimental conditions inherent to online testing.

What you will (mostly) do:You will hear warbling tones at different frequencies, with and without background noise, and will have to adjust their level so that they are just-detectable.

Practical information: The experiment must be performed using headphones, in an environment that is as quiet as possible so that you can focus on the auditory task. Please use a computer (laptop, desktop) and the Chrome browser to ensure compatibility with the online experiment. You must be over 18 to participate, with no known hearing impairment.

Detailed outline of the experiment: There are five steps in the experiment. 1) You will be asked to self-adjust the output sound level on your computer, wearing headphones, so that level is comfortable throughout the experiment. 2) A short test will confirm that you are using headphones. 3) A short level adjustment task will be proposed to calibrate more precisely the volume. 4) and 5) You will be asked to adjust the level of 12 warbling tones at their threshold of audibility. There will be two iterations of this step, one with background noise and one without, performed in a random order.

Duration of the experiment and reward: This experiment is expected to take about 15 minutes in total. You will receive your reward upon completion of the experiment.

Non-participation and/or early termination: You are free to accept or refuse to participate in this study. Your consent does not in any way relieve the research organizers of their responsibilities. You retain all of your rights guaranteed by the law. If you wish, you may stop your participation in the study at any time, without providing any explanation.

Legal notice: We will not collect any personal information other that your Prolific ID. Any data that is obtained in connection with this study will only be analyzed anonymously for the purposes of scientific research in a mission of public interest. No data will be stored outside of the EU. If you have any questions about the study, please contact the research team through Prolific or at Emailing us will reveal your email address to the research team, but that information will be kept confidential. The CNRS Data Protection Officer can also be contacted for any questions about personal data protection: CNRS Data Protection Department, 2 rue Jean Zay, 54519 Vandoeuvre-les-Nancy; mail: If you believe, after having contacted us, that your rights under the French Data Protection Act are not being respected, you can file a complaint online: