FM Stereo Threshold
FM stereo threshold is the antenna signal level at which a tuner switches from mono to stereo reception.
A lower threshold allows stereo operation with a weaker signal, but it does not promise quiet stereo sound. The value may be stated in microvolts, dBf or dBµV. Those scales are not interchangeable numbers, and antenna impedance can matter.
FM Stereo Threshold — Tuner
Automatic stereo reception engages once the tuner's switching criterion is met. A fixed threshold gives one level; an adjustable threshold gives a range of possible settings. This control can change when stereo becomes available, while the received signal still determines noise and stability.
Compare thresholds in the same units and with matching antenna-input conditions, including 75- or 300-ohm references where stated. Do not rank a microvolt number against a dBf number directly. Muting threshold controls whether audio is silenced, while usable sensitivity and quieting sensitivity measure other reception criteria; none is the stereo switching point.