Abstract: A magnetoelectric apparatus for measuring the droplet frequency response at a printhead by applying a method comprising a metallic detecting plate and a magnetic ring, and a method using the foregoing apparatus to determine the maximum droplet frequency response of the printhead. When an ink drop jetted from the nozzle makes contact with the detecting plate, which is perpendicular to the nozzle plate of the printhead, a current flows through the detecting plate immediately, and is detected as a portion of an expected signal. As soon as the ink drop leaves the nozzle completely, the foregoing current no longer exists. However, the magnetic ring generates an induced current that flows in the same direction as that of the foregoing current to complement the absence thereof, wherein the induced current is also detected as another portion of the expected signal. The expected signal is then processed by a signal-processing routine for determining the maximum droplet frequency response of the inkjet printhead.