Question about power compression


Hey Wayne, I have a question about the JBL pro drivers, well all drivers for that matter. The spec sheet for the 12" driver states power compression at different power input levels. At full power 600w, it says the driver has a power compression of 3.9dB. I am assuming that means with an input of 600w, the output will be about 119dB, while assuming the driver had no power compression, output would be around 123dB? Doesnt this basically mean the driver only gains 1.5dB from raising the input power from 300 to 600 watts, since the compression at 300w is 2.4dB? Is this due to thermal heating of the voice coil that causes this effect? I know that when temperature goes up so does resistance, is the power compression refering to this? Or is it refering to mechanical power handling, I dont think it is since mechanical power handling is frequency dependant. What is causing the phenomenon of power compression? Is it this significant in all drivers?

Thanks Wayne (and everyone else)!!!


http://www.pispeakers.com/JBL_2206.pdf


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