As an example, look at these thresholds. The red circles at 250 and
1000 Hz. indicate thresholds plotted in dB SPL for this patient. Both
thresholds are at 35 dB. The threshold of 35 dB SPL at 250 Hz. is
less than 10 dB above the average normal threshold at this frequency
(i.e., 26.5 dB SPL) indicating that at this frequency this patient
has essentially normal hearing.
