The Illuminator tweeters stand for superb vocal rendition and excellent imaging at all listening levels. The D3004/664000 is ”top of the range” with its pure beryllium diaphragm, large roll surround, and AirCirc motor system, it provide a excellent – unsurpassed – sound reproduction with a flat frequency response to above 40KHz, outstanding off-axis response, low distortion and dynamic precision.
Datasheet: Datasheet D3004/664000
Reviews:
Klang & Ton, 06-2009
Voice Coil, 01-2010

Size (inches): 1
Fs (Hz): 500
Re (ohms): 3
Sensitivity (dB): 91.5
Qt: 0.54
VAS (ltr.): 0.02
Xmax ± (mm): 0.2

DIY kits for this driver:
Scan-Speak B741 made by pbn Audio
NADA High End made by Klang+Ton