Been messing about with midi for sometime with the band
and thought I would have a go at making a midi pibgorn. Usinging an existing Yamaha vl70m wind controller module and a BC3a as the midi wind sensor plugged into a £10 viking helmet off ebay as the horns added to my technopipes, the results are very very good, if a little crazy.
The bc3a vents air out of the top horn hole and sends wind midi data to the vl70m, and the bottom hole sends standard note change midi data to the module. I have fitted a bulk head( top half of a kinder egg) between the two hole to stop moisture passing through and a small vent hole at the top of the horn so not to blow the pressure sensor of the bc3a.