Audio earpiece for wideband telephone handsets
View Patent ↗A method of manufacturing a telephony earpiece is provided. The method includes providing a speaker diaphragm and constraining the speaker diaphragm using a cap to provide a thin cavity between the cap and the diaphragm. The first resonance peak of the diaphragm/cavity system is damped by a first slow leak in the cap. The frequency response is built up using a rear resonator in the cap and the high frequency end response is enhanced using a front resonator on an opposite side of said diaphragm as said cap. Positioning of these resonator holes is an important factor. The earpiece is tuned using a second leak to adjust amplitude of low frequency end response.
1. A telephony earpiece device comprising:
a speaker diaphragm;
a rear cap disposed on a rear side of said speaker diaphragm to provide a cavity between said rear cap and said speaker diaphragm, said cavity having dimensions selected to constrain a 00 vibration mode of said speaker diaphragm such that a 00 vibration mode dominates, said rear cap having a slow leak located adjacent a diaphragm nodal line of said 00 vibration mode for damping a first resonance peak and a rear resonator for building a low end frequency response,
said rear resonator having a plurality of rear holes in said rear cap located intermediate of said low leak and a centre area of said rear cap proximal a diaphragm nodal line of said 00 vibration mode; and
a front resonator including a plurality of front holes and a front cavity, said plurality of front holes optimally positioned for enhancing high frequency end response, said front resonator including a leak for adjusting low frequency end response amplitude.
2. The device according to claim 1 wherein said rear cap includes a slot to provide said slow leak.
3. The device according to claim 2 wherein said slot further comprises at least one of a nylon screen and a porous material to facilitate said slow leak.
4. The device according to claim 1 wherein said rear resonator in said rear cap is tuned between about 120 to about 150 Hz.
5. The device according to claim 1 wherein said front resonator enhances a high frequency response of about 6 kHz.
6. The device according to claim 1 wherein said front resonator is molded in a handset.
7. The device according to claim 1 wherein said leak in said front resonator is disposed at the speaker diaphragm to front resonator interface.
8. The device according to claim 1 wherein said wherein said leak in said front resonator is disposed at the front resonator to ear interface.
9. The device according to claim 1 wherein said front resonator has stands on an outer surface for providing said leak in said front resonator.