Microphone having coupled acoustic circuits

Claim 2

A microphone having a response characteristic in a frequency range and a reinforced response at the upper limit of this frequency range, consisting of a housing, an electroacoustic transducer having at least one diaphragm which produces electric output signals as a function of the sound impinging upon the diaphragm, a substantially cylindrical acoustic resonance chamber in the housing directly in front of and coupled to the diaphragm, an opening to said acoustic resonance chamber providing a main sound inlet opening, at least one group of subsidiary sound inlet openings formed in the cylindrical walls of the acoustic resonance chamber and acoustic resistances provided for the subsidiary sound inlet openings.

Claim 3

A microphone according to claim 1, in which two groups of subsidiary sound inlet openings are provided at different distances from the diaphragm, each subsidiary sound inlet opening of one group being at a constant distance from the diaphragm.

Claim 4

A microphone according to claim 2, in which the ratio of the distance of the main sound inlet opening from the diaphragm to the distance of the first group os subsidiary sound inlet openings from the diaphragm has a value of between 1:1.2 and 1: 1.6.

Claim 5

A microphone according to claim 2, in which the ratio of the distance of the first group of the subsidiary sound inlet openings from the diaphragm to the distance of the second group of subsidiary sound inlet openings from the diaphragm has a value within the range of between 1:1.2 and 11:1.6.

Claim 6

A microphone according to claim 1, in which the diaMeter of said acoustic resonance chamber is greater than its length.

Claim 7

A microphone according to claim 1, in which the size of the cross-sectional area of the acoustic resonance chamber is at least equal to the size of the surface of the diaphragm.

Claim 8

A microphone according to claim 1, in which the distance of the main sound inlet opening of the acoustic resonance chamber from the diaphragm is less than the diameter of the diaphragm.

Claim 9

A microphone according to claim 2, further comprising acoustic resistances provided for the subsidiary sound inlet openings, the size of the acoustic resistances being selected so as to decrease with an increase in the distance of the groups of subsidiary sound inlet openings from the diaphragm.

Claim 10

A microphone according to claim 1, in which the housing is formed of a plastic material and the acoustic resistance associated with the subsidiary sound inlet openings are located in the walls of the housing.

Claim 11

A microphone according to claim 1, in which the acoustic resistances associated with the subsidiary sound inlet openings are fastened to the outside of the housing.

Claim 12

A microphone according to claim 1, in which the subsidiary sound inlet openings are of circular cross section.

Claim 13

A microphone according to claim 1, in which the length of the acoustic resonance chamber is at most 20 mm. and the distance of the subsidiary sound inlet openings from the diaphragm is at most 15 mm.

Claim 14

A microphone according to claim 1, further comprising reverse sound inlet openings provided behind the diaphragm.

Claim 15

A microphone according to claim 13 further comprising phase-reversing members provided in said reverse sound inlet openings.

Claim 16

A microphone having a response characteristic within a frequency range and increased response at the upper limit of said frequency range, comprising a housing, an electroacoustic transducer having a diaphragm which produces electric output signals in response to sound impinging upon the diaphragm, an acoustic resonance chamber in the housing in front of the diaphragm having the form of a substantially cylindrical pot, a radial horn directly in front of the diaphragm which extends over the entire cross-sectional area of the acoustic resonance chamber and is fastened to the cylindrical walls of the latter, said horn being permeable to sound in the vicinity of the place of attachment, the opening of the acoustic resonance chamber forming a main sound inlet opening, and at least one group of subsidiary sound inlet openings formed in the cylindrical walls of said chamber, the distance of which from the diaphragm is greater than the distance of the radial horn from the diaphragm.

Claim 17

A microphone having a response characteristic within a frequency range and increased response at the upper limit of said frequency range, comprising a housing, an electroacoustic transducer having a diaphragm which produces electric output signals in response to sound impinging upon the diaphragm, an acoustic resonance chamber in the housing in front of the diaphragm having the form of a substantially cylindrical pot, a radial horn directly in front of the diaphragm which extends over the entire cross-sectional area of the acoustic resonance chamber and is fastened to the cylindrical walls of the latter, said horn being permeable to sound in the vicinity of the place of attachment, the opening of the acoustic resonance chamber forming a main sound inlet opening, and at least one group of subsidiary sound inlet openings formed in the cylindrical walls of said chamber, the distance of which from the diaphragm is greater than the distance of the radial horn from the diaphragm.

Claim 18

A microphone according to claim 15, in which the radial horn consists of a circular plate which is clamped in the housing and is permeable to sound in the vicinity of its place of clamping.