How do I use the filter settings on One?

One allows you to listen with multiple frequency filter choices simply by pressing the "filter" button (top left with audio jack facing right). You can even set two filters that you use most as "favorites," making them super-easy to select.  Filter choices range from very low frequency sounds (low pitched sounds such as S3), to higher frequencies (lung sounds).

The Hz scale on the stethoscope head indicates the filter range selected.  LEDs on the left side of the scale indicate lower frequencies will be reproduced; LEDs on the right indicate higher frequencies will be reproduced. The more LEDs that are on, the wider the range of frequencies;  the narrower the indication, the narrower the range of frequencies for the filter you have selected. 

In addition to filter settings, you can change the frequency response by applying more or less pressure on the diaphragm. As you push on the diaphragm, the "gap" in the sensor changes, which modifies the sensor's response to lower frequencies. 

To find out more about filter settings in One, please see the insert included with the stethoscope ("The Audio Filters in Your One") and check out the
Filter Selection section of the manual.