DEVICE AND METHOD FOR INSPECTING RECORDING/PRODUCING CHARACTERISTICS

PROBLEM TO BE SOLVED: To make uniform an error rate measurement value, enhance inspection reliability, and at the same time improve the tact of an inspection process by providing a low-pass filter that can control both a cut-off frequency and a gain. SOLUTION: A recording signal reproduction circuit in a device for inspecting the error rate of a plurality of rotating storages is formed by a circuit below including a low-pass filter 5. The low-pass filter 5 changes the cut-off frequency and the gain of a frequency band near the cut-off frequency. An error rate measuring means 8 reproduces information recorded in a storage 1 based on a signal that passes through the low-pass filter 5 and compares the reproduction information with recorded information 9 used for recording, thus calculating an error rate. A filter constant control means 11 controls the cut-off frequency and the gain of the low-pass filter 5 so that the measured error rate is within a preset range.