Acoustic parameter measuring equipment and acoustic material measuring equipment

Abstract

This invention discloses an acoustic parameter measuring device and an acoustic material measuring device. A detection tube and a first sound-emitting module disposed at a first opening of the detection tube can be repeatedly used in both the acoustic parameter measuring device and the acoustic material measuring device. Different measuring devices can be formed by replacing the module connected to a second opening of the detection tube. Setting the first detection module at the second opening constitutes an acoustic parameter measuring device for measuring the acoustic parameters of a microphone under test; setting the second sound-emitting module at the second opening constitutes an acoustic material measuring device for measuring the acoustic parameters of an acoustic material under test. This invention, by providing a structure with a detection tube and a first sound-emitting module, allows for different acoustic measurements to be performed on various products under test by changing some modules.

Claims

1. An acoustic parameter measuring device, comprising: A detection tube (1) has a side wall (11) on which at least one detection hole (111) is provided. The two ends of the detection tube (1) opposite to each other along the axis have a first opening (12) and a second opening (13), respectively. A first sound-emitting module (2) is provided at the first opening (12). The first sound-emitting module (2) has a first loudspeaker (21) for emitting a first detection sound signal and a second cancellation sound signal. A second sound-emitting module (3) is detachably connected to the second opening (13). The second sound-emitting module (3) has a second loudspeaker (31) for emitting a first cancellation sound signal and a second detection sound signal. A control circuit (10) is provided. The first loudspeaker (21) and the second loudspeaker (31) are electrically connected to the control circuit (10), respectively. The control circuit (10) is electrically connected to a reference microphone (4), and the detection tube (1) is configured to allow a microphone (51) to be tested to pass through and extend into the detection hole (111); the first detection sound signal and the first cancellation sound signal are superimposed to form a first reference signal, and the second detection sound signal and the second cancellation sound signal are superimposed to form a second reference signal; the reference microphone (4) collects the first reference signal and the second reference signal, the control circuit (10) generates a first cancellation signal based on the first reference signal, and the control circuit (10) generates a second cancellation signal based on the second reference signal; the first sound-emitting module (2) includes a first sound-absorbing material (22) disposed on one side of the first speaker (21), and the first sound-absorbing material (22) wraps the rear end of the first speaker (21).

2. The acoustic parameter measuring device as described in claim 1, wherein, The control circuit (10) is configured to send a first detection signal to the first speaker (21) to cause the first speaker (21) to emit the first detection sound signal, and to send the first cancellation signal to the second speaker (31) to cause the second speaker (31) to emit the first cancellation sound signal; the control circuit (10) is also configured to send a second detection signal to the second speaker (31) to cause the second speaker (31) to emit the second detection sound signal, and to send the second cancellation signal to the first speaker (21) to cause the first speaker (21) to emit the second cancellation sound signal.

3. The acoustic parameter measuring device as described in claim 2, wherein, The control circuit (10) includes a signal delay device (8), which is a first filter or a delay component.

4. The acoustic parameter measuring device as described in claim 1, wherein, The reference microphone (4) includes a first reference microphone (41) and a second reference microphone (42). The first reference microphone (41) is positioned close to the first sound-emitting module (2) and receives the second reference signal. The second reference microphone (42) is positioned close to the second sound-emitting module (3) and receives the first reference signal.

5. The acoustic parameter measuring device as described in claim 4, wherein, The control circuit (10) also includes a second filter (9).

6. The acoustic parameter measuring device as described in claim 5, wherein, The second filter (9) is a minimum mean square filter.

7. The acoustic parameter measuring device as described in claim 6, wherein, When the control circuit (10) sends the first detection signal to the first speaker (21) and the first cancellation signal to the second speaker (31), the signal delay device (8) is configured to delay the output of the first cancellation signal, and the second filter (9) is configured to correct the first cancellation signal; when the control circuit (10) sends the second detection signal to the second speaker (31) and the second cancellation signal to the first speaker (21), the signal delay device (8) is configured to delay the output of the second cancellation signal, and the second filter (9) is configured to correct the second cancellation signal.

8. The acoustic parameter measuring device as described in claim 7, wherein, The first sound-emitting module (2) further includes the first sound-absorbing material (22) disposed on the side of the first speaker (21) away from the second speaker (31); and / or the second sound-emitting module (3) further includes a second sound-absorbing material (32) disposed on the side of the second speaker (31) away from the first speaker (21).

9. The acoustic parameter measuring device as described in claim 1, wherein, At least one of the detection holes (111) is at the same distance from the first speaker (21) as it is from the second speaker (31).

10. The acoustic parameter measuring device as claimed in claim 1, wherein, The inner diameter of the test tube (1) is 6cm and the length is 50cm.

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