How to see the waterfall diagram of earphone frequency response? The waterfall map is very detailed.

The horizontal axis X axis is the frequency scale, the right is 20hz, the right is 20000hz, and the y axis is the sound pressure level in dB. As shown in the figure, the red line is the sound pressure-frequency response curve at the beginning of 0 milliseconds, which is called frequency response curve for short.

Arranging the frequency response curves of every millisecond on the Z axis (that is, the coordinate axis of the 45-degree diagonal on the diagram) in time increments, we can observe which frequency ranges of acoustic energy slowly decay with the passage of time, which shows that there are steep curve groups similar to ridges on the diagram, rather than the "foot of the mountain" with zero sound pressure level (blue parallel lines densely arranged on the diagram).

The ideal waterfall diagram is that there is only one curve at 0 millisecond, which means that the earphone diaphragm stops moving immediately after the input pulse signal disappears in the next millisecond. Of course, this is impossible. The actual situation is that the waterfall graph will decay rapidly with the passage of time, and all points on the whole frequency response curve will decay at the same speed. Generally, it is normal that the low-frequency attenuation rate is relatively slow.

The two narrow ridge curve groups in the right high frequency band in the figure indicate that the design of the earphone vibration part is not ideal, and there is long-term vibration, which leads to poor transient response in the corresponding frequency band.