| 摘要 |
FIELD: instruments for measuring sound absorption and specific acoustic impedance in materials under investigation of coincident wave. SUBSTANCE: expensive speaker which has high-precision holes in permanent magnet body and diaphragm for passing acoustic probe is replaced by inexpensive speaker of simplified design so that probe is inserted into measuring tube from casing side through hole which is made in casing and tested sample instead of insertion from housing side through hole in its bottom. EFFECT: decreased parasitic oscillation of probe caused by speaker, increased precision. 2 dwge |
