Tweeter Test (9 kHz Spectral Tone)

The 9 kHz spectral tone is used for tweeter or high frequency evaluation. This tone is a section of frequencies of equal amplitudes that ranges from 8.5 kHz to 9.5 kHz. This sounds like a group of crickets chirping.

The spectral tone is used for the following 2 reasons:
^ Easier to locate the source, much like the warble tone
^ Easier to identify for those people with high-end hearing loss problems