Originally Posted by robertcharles
Below tuning, the woofer can unload. At this point, the driver could effectively destroy itself if you give it too much power. This is not the old days of 30 watt per channel amps. Nowadays, huge amplifiers with tremendous power on tap can crinkle drivers if you give them a chance. So, yes use a vented enclosure to obtain the SPL you desire, but HPF the system so you can enjoy it for a long time. You will be very happy you did.
Can WinISD models be trusted to estimate the unloading?
If I read my model correctly, while excursion goes up below tuning, it's only slightly over Xmax at 10Hz.
600W signal into dual D4 in 12 cu.ft with 14 Hz tune.
Is it safe not to use HPF in this case?
But if all output below tuning is garbage then there is no reason to take the risk any way