ESS amt-monitor
Price unknown (1 unit, around 1970 s?)
Commentary
A floor-type speaker system developed as a top-of-the-line ESS model.
The amt-monitor has a Hail driver in the high range, a 30 cm cone woofer and a 30 cm passive radiator in the low range.
The Hail driver has a structure in which Teflon accordion pleats are placed in a strong magnetic field and elements (conductive bands) are embedded in the sides of each of the pleats.
When a signal is applied to this element, an electric current flows and the movement of the folds compresses air and emits sound into space.
Because the voice coil radiates sound directly into space by this operation, excellent damping characteristics and low distortion factor are achieved.
The 30 cm woofer cone used in the low range uses a polystyrene compound called bexstrene, which is different from pulp and was developed by BBC engineers.
Also, the 30 cm passive radiator is mounted on the front side along with the woofer.
The enclosure is made of walnut and has sufficient volume for low sound reproduction below 30 Hz.
Model Rating
Method | 2-way, 2-speaker, passive radiator system ・ Floor type |
Units Used | For low band : 30 cm cone type High pass : Hail Driver Passive radiator : 30 cm cone type |
Frequency characteristic | 30 Hz to 23 kHz ± 3 dB |
Output sound pressure level | 90dB/W |
Allowable input | 375W Clean Power |
Crossover frequency | 1kHz |
External dimensions | Width 397x Height 997x Depth 403 mm |
Weight | 47kg |