Thanks so much Greg. Much appreciated. This shiws me that this driver most likely isnt the driver made for a known OEM for a very specific design/model. Although, the 25Hz 5cuft tune does look rather good, and would have in room response into the 18Hz spectrum quite easily and would maintain a realtively flat response to 25Hz. I was inquiring on using these drivers in a three way cab capable of full range coverage, including sub 20 material. The design I was comparing was indeed an 18Hz tune. Again thank you for those runs. Im not able to access my PC to do so.