Approximately four years old, pulled fully working from a franken-scala project I threw together and am now dismantling to pursue other things. Qty 4 drivers total, will sell in pairs and will be shipped with original OEM boxes/packaging.
Currently selling from ESS for $250/each, I'm selling these for $375/pair, shipped and paypal'd in the conUS.
Invented by the noted physicist and scientist, Dr. Oskar Heil, the ESS Heil Air Motion Transformer (AMT) tweeter uses a folded pleated Mylar diaphragm just 0.0005" thick. Its voice coil is a serpentine pattern of precision-etched aluminum, selected for minimal weight and high power handling.
https://essspeakers.store/collections/heil-amt/products/original-great-ess-heil-air-motion-transformer™-i-large
Unlike a normal piston loudspeaker that excites the air by alternately pushing and pulling a cone or dome, the Heil AMT Air Motion Transformer linearly squeezes and expands its diaphragm's pleats, moving the airload at a very high velocity. Because the moving mass of the Air Motion Transformer is extremely low and the magnetic structure very powerful, this combination results in extremely high acceleration that yields amazing transients.
Weight: 14.5 pounds
Height: 6″
Width: 6.75″
Depth: 4.25″
Impedance: 4 ohms, Re: 3.9 ohms
Power: 40 Watts RMS, 160 Watts Max
Response: 20 kHz - 800 Hz
Sensitivity: 96 dB, 1 watt, 1 meter
Fits ESS Cabinet and Driver Models:
ESS: AMT-1. AMT1, AMT-1A, AMT-1B, and many more