Frequency right on 6 kHz, intermediate.

Frequency is lower than standards, but otherwise highly suggestive of PSFL.

Both frequency range and the equal emphasis of the tick and the middle note make this an intermediate specimen. The middle note is unusually high compared to the final note. PSFL rarely show this middle note, but its frequency is appropriate for the final note of a PSFL.

This note appears visually to be discontinuous. Listen to it, though, and it sounds continuous like a PSFL. The frequency dip is also a PSFL character. It's just far too low for a PSFL, and that's the reason for the poor aural match with the PSFL examples. So, intermediate.

No Sample