Line microphones have been popular as narrow directional microphones for a long time. Their structure adopts a leaky acoustical tube with many slits to suppress off-axis sensitivity, together with a directional capsule attached to this tube. Although many microphones of this type are on the market, we have no quantitative theory to explain its behavior, which is very important for effectively designing directivity. We thus modeled the leaky acoustical tube using a distributed equivalent circuit and combined it with the directional capsule’s equivalent circuit model. The analysis showed that the model agreed well with the measurement results, particularly at the directional characteristics, while an ordinary model of acoustical tube using delay and sum modeling did not.
Click to purchase paper as a non-member or login as an AES member. If your company or school subscribes to the E-Library then switch to the institutional version. If you are not an AES member and would like to subscribe to the E-Library then Join the AES!
This paper costs $33 for non-members and is free for AES members and E-Library subscribers.