Enhancing Externalization of Frontal Virtual Sound Sources in Binaural Synthesis via Level and Reflection Adjustment of Non-individualized BRIRs.

Very small samples: 9 listeners in Experiment I and 10 in each Experiment II condition, all graduate students with self-reported normal hearing. Only pink noise was tested. The authors note that speech has an intermittent nature and restricted frequency range, so the method's effectiveness for speech is uncertain and may be more limited. The subjective listening test used only Room B, even though the scaling factors were derived from all four rooms. Generalizability to other room acoustics is inferred, not tested. No individualized BRIRs were used, and the study did not compare against them, so the absolute ceiling of externalization achievable is unknown. The study did not measure localization accuracy or distance perception directly; participants reported no noticeable degradation, but this was not formally tested.

The authors declared no financial support and no potential conflicts of interest.

Do not assume these findings apply to speech or music. Only pink noise was tested, and the authors themselves note that speech's intermittent nature and restricted frequency range may limit the method's effectiveness. The samples were also very small (9 and 10 listeners, all graduate students), so the large effect sizes come from a single small group and have not been replicated in a broader or clinical population.