MICROPHONE/SPEAKER DEVICE
Embodiments provide a microphone/speaker assembly such as a headphone or headset which comprises a mechanical acoustical low pass filter between the microphone and the speaker so as to effectively attenuate higher frequencies fed back to the microphone. The low pass filter may comprise a hole or tunnel which connects a front volume of the microphone with a front volume of the speaker, providing a reliable and effective stable structure. An attenuation material may be provided for adjusting the attenuation of the low pass filter. Other embodiments provide side-by-side microphone and speaker so that the microphone does not distort the speaker acoustic path.
1 - 10 . (canceled)
11 . A microphone/speaker assembly comprising:
a microphone and
a speaker,
wherein a mechanical acoustical low pass filter is provided between the microphone and the speaker, wherein the low pass filter comprises a hole or tunnel which connects a front volume of the microphone with a front volume of the speaker, wherein the assembly further comprises a separation wall between a front volume of the microphone and a front volume of the speaker and the hole or tunnel is arranged between the separation wall and an internal wall of a housing of the microphone assembly.
12 . The microphone/speaker assembly as recited in claim 11 , wherein the hole or tunnel has a round or circular cross-section or a polyangular or rectangular shape.
13 . The microphone/speaker assembly as recited in claim 11 wherein the hole or tunnel has an opening size from about 0.2 mm to about 2 mm, and/or the hole or tunnel has a length from about 1 mm to about 5 mm.
14 . The microphone/speaker assembly as recited in claim 13 wherein the hole or tunnel has an opening size from about 0.3 mm to about 1 mm, and/or the hole or tunnel has a length from about 1.5 mm to about 3 mm.
15 . The microphone/speaker assembly as recited in claim 14 wherein the hole or tunnel has an opening size of about 0.5 mm and/or the hole or tunnel has a length of about 2 mm.
16 . The microphone/speaker assembly as recited in claim 1 , wherein the separation wall comprises an angular part extending parallel to an internal wall of the housing of the microphone assembly.
17 . The microphone/speaker assembly as recited in claim 11 , comprising an attenuation material for adjusting the attenuation of the low pass filter comprising an acoustic fabric or mesh arranged at or in a hole or tunnel of the low pass filter or an acoustic foam arranged at or in a microphone front volume.
18 . The microphone/speaker assembly as recited in claim 7 , wherein the mesh is attached to the separation wall and the housing.
19 . The microphone/speaker assembly as recited in claim 1 , wherein the upper corner frequency of the low pass filter is set in the range of about 1 kHz to about 20 kHz.
20 . The microphone/speaker assembly as recited in claim 19 , wherein the upper corner frequency of the low pass filter is set in the range of about 2 kHz to about 10 kHz.
21 . The microphone/speaker assembly as recited in claim 20 , wherein the upper corner frequency of the low pass filter is set in the range of about 4 kHz to about 8 kHz.
22 . The microphone/speaker assembly as recited in claim 21 , wherein the upper corner frequency of the low pass filter is set at about 4 kHz.
23 . The microphone/speaker assembly as recited in claim 11 , wherein the microphone and speaker are arranged side-by-side in a plane perpendicular to the direction of sound projection to the user.
24 . The microphone/speaker assembly as recited in claim 11 , comprising a tube adapted for insertion into a human ear.
25 . The microphone/speaker assembly as recited in claim 11 , wherein the microphone/speaker assembly is at least one of a headphone, an in-ear-canal headphone, and a headset, with feedback noise reduction or cancellation.