The
destructive test done on a stock LAB12 driver was performed with 40VRMS, 40Hz, cycled 15 seconds on and 15 seconds off. It failed after about an hour, the voice coil had separated.
Eminence inspected the damaged speaker and said there was no manufacturing defect.
The
heat exchanger test used a LAB12 driver driven constantly for several days, at power levels from 40VRMS up to 60VRMS. The same test signal was used, 40Hz cycled 15 seconds on and 15 seconds off. A fixed voltage level was used for two hours, then the temperature was measured and the drive voltage increased 2v and run for another 2 hours.
Tests showed the electro-mechanical parameters shift less at high power levels. This makes the response curve more linear at high power, as is shown in the measured response from the Prosound Shootout. The device increases power handling, improves longevity, reduces compression and improves response linearity at high power levels.
Why speculate? Build one yourself and test it.