There are two ways to change filter settings on the Thinklabs One.
OPTION 1: Press and hold the Filter button for two seconds and then release it when the LED on the Filter Scale moves one position, as shown in the following image.
NOTE: The filters on the left end of the scale are for Bell frequencies, while the filters on the right are for Diaphragm frequencies. When all LEDs are lit, full bandwidth is selected, which means no filter is used.
OPTION 2: Press the Filter button and then immediately release it to "jump" between the two favorite filters set on the device. Press it again and release to "jump" back.
For more information on setting favorite filters, click here.