Scan-Speak Revelator D2904/710002 26mm Dome Tweeter 4ohm, Large Ring Neo, Silver Faceplate The Revelator Tweeters large roll surround technology represents a breakthrough in overall performance, with outstanding off-axis response, high output capability and low resonance frequency. Additional enhancements have been made to reduce distortion and power compression, such as large neodymium magnet systems for high sensitivity, and a careful design to optimise airflow in the chambers. - 1" Coated Textile Diaphragm - Large Roll Surround f. Wide Dispersion - Patented Symmetrical Drive (SD-2) motor - Large Ring Neo Magnet f. High Output - Non Resonant Alu Rear Chamber - Silver Anodized Machined Alu Face Plate