a picture speaks a thousand words, this is with 200W (at 1m). 40Hz is the goal and this driver can do that with a small port in a small box. It's totally unsuited to a bigger box and a bigger port as the port output gets out of controlHow low are you hoping for it to go to.
see above for why I still plan to get the td12x for the LCRLots cheaper than the TD12X!!!