Acoustic resistance detection device and acoustic resistance adjusting method of acoustic resistance material

Abstract

The invention relates to an acoustic resistance detection device and an acoustic resistance adjusting method of acoustic resistance material. Compared with the acoustic resistance value of reference acoustic resistance material, the detection of acoustic resistance value of the detected acoustic resistance material has low price and no fault. The acoustic resistance detection device includes a first fitting pipe, one end (10a) of which is connected to a compressed air supply source (C); a pipe end on one side of the other end (10b) is provided with a reference acoustic resistance material (S); a middle part is provided with an air throttling part (11); the acoustic resistance detection device further includes a second fitting pipe having the same structure as the first pipe (10); one end (20a) of the second fitting pipe is connected to the compressed air supply source (C); the pipe end on one side of the other end (20b) is provided with a detected acoustic resistance material (X); the middle part is provided with an air throttling part (21) having the same air resistance value as the air throttling part (11); the downstream sides of the air throttling parts (11, 21) of the first and second fitting pipe (10, 20) are connected with area flowmeters (12, 22) having buoys (12n, 22n); the acoustic resistance value of the detected acoustic resistance material X is detected by the height position of the buoys (12n, 22n).

Description

technical field [0001] The present invention relates to a device for measuring the acoustic resistance of an acoustic resistance material used in a microphone and a method for adjusting the acoustic resistance of the acoustic resistance material. Adjusted technique. Background technique [0002] The primary sound pressure inclination type condenser microphone has a rear sound terminal, and an acoustic resistance such as a nylon mesh or a sponge with continuous air bubbles is arranged on the sound wave path from the rear sound terminal to the back of the diaphragm. material (for example, refer to Patent Document 1 (Japanese Patent Laid-Open No. 2000-50386 A)). [0003] Usually, for the acoustic resistance material on the side of the rear audio terminal, for example, it is installed on the back of the stationary pole support base with a sound hole (sound wave introduction hole) via an adjustment nut, and the tightening force of the adjustment nut is increased or decreased, th...

AI Technical Summary

Problems solved by technology

[0011] However, as the differential pressure gauge of the acoustic resistance measuring device, it is preferable to use a differential pressure gauge having a differential pressure sensor formed of a semiconductor from the viewpoint of accuracy, but such a differential pressure gauge is expensive.

In addition, for example, when the acoustic resistance value of the reference acoustic resistance material and the acoustic resistance value of the measured acoustic resistance material are far apart, if an excessive differential pressure is applied to the differential pressure gauge, the differential pressure gauge may malfunction.

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