| 摘要 |
<p>The application relates to a test system for evaluating acoustic feedback characteristics of a listening device by changing the transfer function of the signal path from an acoustic output to an acoustic input of the listening device. The application further relates to a method of characterizing acoustic feedback at different frequencies in a listening device and to the use of a test system. The object of the present application is to provide a tool for verifying acoustic feedback in a listening device at different frequencies. The problem is solved in that a) a variable filter comprising an acoustic input and an acoustic output, the variable filter comprising a control unit for changing a transfer function of the filter; b) first and second acoustic propagation elements for propagating acoustic sound, the first acoustic propagation element acoustically connecting the acoustic output of the listening device with the acoustic input of the variable filter, the second acoustic propagation element acoustically connecting the acoustic output of the variable filter with the acoustic input of the listening device; wherein the system is configured to allow a determination of acoustic feedback or a level of acoustic feedback of the listening device at different frequencies. This has the advantage of allowing a determination of frequencies where a particular listening device is prone to acoustic feedback. The invention may e.g. be used in hearing aids, headsets, telephone sets, etc.</p> |
