Interacoustics AS608 Operation Manual page 21

Select the frequencies to include in the HW test. Press Change to
toggle between frequencies On/Off.
Press Save to return to the main HW setup menu.
Frequencies
Press Change to access the default frequency range from 125Hz to
8 kHz for daily operation.
7 frequencies are available to change: 125, 250, 750, 1,500, 3,000,
6,000 and 8,000.
Press Change to toggle between On or Off.
Press Save to return to the main setup menu.
License.
AS608/AS608e Operation Manual Page17