I have not had ANY luck with Regnar/Dahlquist site. They have never responded to my inquiries. Madisound sells an upgrade to the Vifa tweeter: I have to replace the vifa's voice coil/diaphram and they are near impossible to find. Madisound has an upgrade to the tweeter:
SEAS Prestige 27TBFC/G (H1212) Aluminum/Magnesium Dome Tweeter
