Model OST-828 can measurement lowest resonant frequency(Fo) and impedance(Ze) of the speaker by the constant voltage anodizing. This model collects the statistics with plural measurements and calculates and does the stanard judgment.
All the measurement data can save it. Futhermore, this model calculates the value of Q(Electrical Q of driver, Mechanical Q of driver, Total Q of driver).
Model OST-727 is a measuring instrument which measures displacement of a cone paper excited by a drive speaker with a displacement sensor, and sets frequency at the displacement peak value to Fo according to direct method.