I wouldn't worry about the dip you see in the published response curve of the Kappa 15LF. Eminence does not typically measure their drivers in an appropriate enclosure under real world conditions as I'm sure Wayne can also attest. I can recall reading in more than one article (I can't remember the sources right now) that one shouldn't take the published response graph of ANY woofer very seriously in the range below 200 Hz. The reason being for this is that under the test conditions, more often than not there are response nulls caused by the measuring room and equipment itself. Its nearly impossible to get a truely accurate picture of a woofer's capability for deep bass response from a manufacturer's published response graph. All these graphs are really good for is to show what happens at the TOP of the woofer's useable range where it will generally start to "break up" and distort. You might remember that for a brief time, I was seriously considering using the Kappa 15LFA instead of a Delta 15 for a modified set of Theatre Four Pi's. I changed my mind when I saw that the Delta 15 has some nasty peaks in the frequency response above 1.6K. It really should be crossed over below 1K, which means it wouldn't mate well with the Eminence PSD2002.

So yes, I stand by my recommendation for the Kappa 15LFA for subwoofer duty.

Colin