Figure 4.

Comparison of differences (top) and absolute differences (bottom) between SPL_terminal and IPL_entrance across frequency for the three probe tips, collapsed across test cavities. For each probe tip, the shaded area encloses the minimum and maximum SPL-IPL differences across the test cavities. Differences between SPL_terminal and IPL_entrance are the smallest at frequencies below 4 kHz for all three probe tips. Below 10 kHz, differences are ≤2.5 dB. Above 14 kHz, differences are the largest for the standard ER10D tip (black shading).