An Acousto-magnetic system is like a magnetic system, this technology uses detectors that emit round of frequency that will cause the amorphous metal in the tag to vibrate. The vibration will trigger a detector in order to cause a change in the magnetization in the strip which includes an AC voltage in the detector. A newer acousto-magnetic system has the capability to safeguard wide exits and high-speed label applications in order to transmit a surveillance area for tags and labels. A transmitter would send aradio frequency signal (approximately 58 kHz) in pulses, which would energize a tag in the surveillance zone.

Also see Electronic Article Surveillance (EAS)