Patent ID: 7596238

Claim:
A howling margin measuring device comprising processing means composed of gain controlling means and a compressor which are connected in series and controlling means, wherein the gain controlling means outputs an input sound signal after giving a gain thereto; wherein if the level of a sound signal input to the compressor is equal to or higher than a threshold level, the compressor outputs the sound signal after compressing it with a specified ratio; wherein the controlling means is capable of controlling the gain of the gain controlling means and reading from the compressor the compression amount level of the sound signal in the compressor at certain time intervals; and wherein the controlling means reads from the compressor the compression amount level of the sound signal at certain time intervals in a case where the compressor compresses the sound signal with the specified ratio while gradually increasing the gain of the gain controlling means, determines whether or not howling has been generated based on whether the read compression amount level has a value equal to or higher than a specified value, and calculates a howling margin based on the gain of the gain controlling means when it is determined that howling has been generated.