The AT28 is a wide-band tweeter with a 28mm coil diameter. It uses two rear chambers, one behind the voice coil and a second milled aluminum chamber behind the motor. Shorting rings are used in the motor to flatten the impedance curve and wick away heat from the coil windings. The proprietary fabric dome has a range extending 10,000Hz past the hearing capability of the human ear. Countless hours of listening has been done to “tune” this tweeter via each part, glue joint, and assembly step. The result is the most listenable tweeter which will reveal details you never knew existed.