PP Slot Loaded Sub with Alpine SWR 12D2

[BP1Fanatic]

I think if the model does not change with the vent blowing by the driver face, something is wrong with the model? That’s why tapped horns are different than a plain back loaded horn. There is acoustical feedback between the front and the back via the vent. This will change the response drastically - reduce the upper bandwidth and improve cone movement control for higher SPL.

Look at how HR is used to model tapped horns - the same driver front and back is exposed to two different paths of the speaker.

You are right, there is a difference. The frequency response lines are basically the same, however, the OD PPSL is more efficient than the TH PPSL. The driver in the path is lowering the volume of the segment in a BP6S compared to a BP6P.