Quote Originally Posted by cradeldorf View Post

I'm kinda confused as to what OG is trying to say about the horn not loading the phram? I would thing the metal Phase plug with the hair width circular slots in it would do the phram loading? I am running the loading caps right now.

Yes, OG is absolutely right.

For such a small horn, trying to xover it too low may damage the phram, as the air-mass (volume of air inside the horn) will be too less to prevent it from being over-excursed. On the other hand, the phase-plug as the name suggests, only prevents any phase cancellation from occuring within the prescribed bandwidth, which otherwise can happen as the phram is not a flat surface, and hence the path length from the periphery & the center of it to a point in front of it in space will be unequal. This difference will cause frequency cancellations at different spots throughout the bandwidth. The loading-caps when 'ON' will also prevent the phrams to some extent from being over-excursed, but it usually is the happiest when the pressure/loading on both the sides are similar (linear excursion), which will not happen here for this horn if the xover was too low, even though the caps were on.