Hi, i love the Automoth ,.its really awesome! Would you all ever consider building an Ultrasound play back speaker .. Its seems like that Would be easy ,compared to building the Automoth, but I don’t know .. there are a few out there , these are used a acoustic bat lure . thanks https://www.apodemus.eu/batlure https://batsound.com/product/l400-ultrasound-speaker/ https://peersonic.co.uk/playback