| 摘要 |
PROBLEM TO BE SOLVED: To set the sound volume of a test tone during a check of a speaker to a proper value when the speaker is checked with a test tone signal. SOLUTION: A test tone signal is generated by adding a fundamental tone signal and a plurality of harmonic signals and a plurality of test tone signals STC to STRB are generated by making frequency components different. The test tone signals STC to STRB are supplied to object speakers 14C to 14RB at the same time. A picked-up sound signal SMS of test tones output from the speakers 14C to 14RB is frequency-analyzed to find energy values of the test tones output from the speakers 14C to 14RB by the speakers. Levels of the test tone signals STC to STRB are increased by a specified value at each time until results of comparisons between the found energy values and a prescribed value exceed the prescribed value to repeatedly output the test tones. When the comparison results exceed the prescribed value, subsequent primary processing is carried out with current levels of the test tone signals STC to STRB. COPYRIGHT: (C)2007,JPO&INPIT
|
