Thiele/Small Parameters

Fs Also called F0, resonance frequency measured in hertz (Hz). The frequency at which the combination of th e energy stored in the moving mass and suspension com pliance is maximum, and results in maximum cone velocity. A more compliant suspension or a larger m oving mass will cause a lower resonance frequency, and vice versa. Usually it is less efficient to pro duce output at frequencies below F s, and input signals significantly below Fs can cause large excursions, mechanically endangeri ng the driver. Woofers typically have an Fs in the range of 13–60 Hz. Midranges usually have a n Fs in the range of 60–500 Hz and tweeters between 500 Hz and 4 kHz. A typical factory toleran ce for Fs spec is ±15%.