DM-4, Dreams AMT Wideband Driver

          Most commonly used by hi-fi industry today for making the ribbon tweeters (also used by M&D’s pleated Dreams AMT drivers), the etched aluminum circuitry is laid on a very thin 0.025mm (1.0mil) polyimide (also known as Kapton) film as the substrate to constitute the voice diaphragm; due to the outstanding characteristics of polyimide such as extremely light weight, high temperature resistance (180-250ºC), excellent durability, and so forth.

             However, from M&D’s own study, we found that the attached mass and hardness of the present polyimide substrate could still amount to certain obstruction for perfect diaphragm movements during sound reproduction. In order to further cut down the substrate moving mass and enhance the pleated diaphragm compliance, after long research, M&D has developed the unique technique and craft to further reduce the substrate to only one-half of its original thickness. This successful development allows us to apply the rare, super-thin 0.0125mm (0.5mil) polyimide material in re-formulating our new Dreams series voice diaphragms.

             Not only this 0.5 mil super-thin polyimide itself incurs much expensive production cost, the higher level of skilled craftsmanship throughout the entire manufacturing process of the Dreams diaphragm are painstakingly time consuming. However, this innovative breakthrough has been proven worthwhile; the new DM-4 wideband driver exhibits significant improvement over the original  version on operating bandwidth, transient response, and sound quality characteristics.

             DM-4 is a true 5 octaves wideband reproducer that responsible from 700Hz up to 25 KHz with low FMD pollution, high output, and satisfactory dispersion characteristics over the complete operating band.

             The DM-4 has a large diaphragm (32X more than a typical 1” dome tweeter), composed of 32 units of lightweight micro-elements, and a total of 14 units of NdFeB strong magnets; typical DC impedance of the DM-4 is 4.5 Ohms (±0.3 Ohms), completely resistive throughout the entire audio band, without resonance, and without inductive or capacitive colorations. This perfect impedance characteristic provides a highly stable operation to power amplifier.

             DM-4 has the efficiency to 85dB/2.83V/1m in average while used as the wideband driver; the module is sized (H) 122mm x (W) 88mm x (D) 27mm, and the iron frame is rigid and heavy in construction with each module weighing up to 760g (1.7 lb).

             Different from an assembly line produced product, the manufacturing process of the Dreams module is both time and labor intensive, requiring extensive hours and hours to assemble and test. Rather than just a simple, mass-produced, assembly line manufactured tweeter, the Dreams driver requires utmost dedication in both precision technology and artistic craftsmanship throughout its creation.