I replaced KSN1038 with APT80 plus 3-order (non optimized) filter:
3.3uF,0.27mH,10uF. Attenuator is 4.4 Ohm series and 6.8 Ohm parallel.The tweeter don't integrate with Alpha 10 as well as piezo do. I think Alpha 10
and KSN1038 is really a rare match. I switched back to piezos.
v.