Two methods to measure the acoustic input impedance of a horn are compared. The first method measures standing-wave patterns in a tube which is loaded by the horn. The input impedance is calculated from the position of the first minimum in the standing-wave pattern and the ratio of maximum to minimum sound pressure levels in the tube. Second a direct method was applied. A novel flow sensor, the microflown, is used together with a pressure microphone, which are mounted in the throat of the horn. Results from both measurements are compared with simulated models.

Two methods to measur e the acoustic input impedance of a horn are compar ed. First method measures standing wave patterns in a tube which is loaded by the horn. The input impedance is calculated from the position of the first minimum in the standing wave pattern, and the ratio of maximum and minimum sound pressure level in the tube. Secondly we applied a direct method. A novel flow sensor, the microflown, is used together with a pr essure micr ophone, which are mounted in the throat of the horn. Results from both measurements are compared with simulated models.