High quality piezo calotte tweeter with funnel this tweeter can be connected directly to the amplifier or to a frequency point the tweeter has a bulging aluminium calotte and no cone membrane owing to the aluminium calotte the sound pressure is not so high as compared to other similar piezo tweeters but for that the loudspeaker has a very wide radiation angle and an excellent brilliant sound through its aluminium calotte having especially low inertia with the low movable mass the frequency