Individual audiogram represents hearing thresholds (softest audible sounds) at different frequencies. At least two test frequencies are used involving one in the lower region of device's bandwidth (such as 750 Hz) and one in the higher region of the device's bandwidth (such as 2 kHz). Hearing thresholds are assessed by presenting pure tones of different known levels (SPL) to the user and the thresholds for each of the test frequencies are determined according to the user response to a verbally formulated question (how many tones did you hear?) and multiple choice answer buttons (0, 1, or 2).