DDZ91

DIGITAL DESIGNS introduced the unique Z Motor design to the market in 2005. This innovative motor structure set new standards for high-end, high-power speaker design resulting in the numerous DD Z woofer copies hitting the market. DD woofers continue to be the blueprint for state-of-the-art speakers as we push for higher and higher performance. We have a passion for performance which forces us to scrutinize every facet of design and every material used in the construction. We look for ways to make new levels of performance available to more and more people. These new Series of Z woofers bring Z Motor technology within reach of every enthusiast.

The heart of the Z motor technology is the concentrated focus of the magnetic array lenses. Rare earth magnets are arrayed and focused to achieve the highest levels of flux possible in order to provide brutally strong magnetic fields for the voice coil to interact. These motors are nearly twice as strong as our largest strontium ferrite motors while taking less space and half the mass. It takes nearly 30 parts to build a focused array rather than around half a dozen to build a ferrite motor; the system is far more complex resulting in much higher energy being delivered to the magnetic gap; twice the energy and half the size.

The Z Motor design was also highly influenced by optimal cooling. As efficient as the Z structure is, most of the power in audio transducers produces heat. We spent over 10 years working on the Z Motor project to optimize both magnetic energy and heat dissipation. Our work on the Free Flow Cooling System has been copied far and wide as we continue to engineer higher heat flow from the coil to the surrounding air. The Z Motor adds more gap cooling as well as continuous outflow of heat from above and below the gap. There simply is no trapped heat in the motor to continually raise the coil temperatures. The harder a Z motor is worked, the higher the volume of air is pumped through and around the voice coil. Short of running square waves or DC current though the coil, it is quite difficult to attain 500 degree plus working coil temperatures in a Z Motor.

The Z91 motor is optimized for powerful coil control over longer excursion ranges. The chief objective was to optimize transient response. This was accomplished via lowering of moving masses, lowering inductance and increasing gap energy.

The flat wire aluminum coil was designed with a thin cross section to keep the magnetic gap as tight as possible. The winding length of over 110mm allows long excursions, over 75mm(3 inches), with 100% of the coil under magnetic control at all times.

All moving parts were scrutinized to reduce mass where possible and parts redesigned to optimize strength to weight ratios.

The suspension system is designed to take advantage of medium power installs and preferably with high definition amplifiers. The Z91 can be ordered with an special, optional Kevlar cone designed to reduce moving mass. A 2mm foam core is sandwiched between ultra light, tapered thickness, multi-layered Kevlar skins. The thickness is increased at the coil apex to minimize possible cone flex while tapering to the outer diameter to reduce unnecessary weight. The resin used is aerospace grade epoxy which is then vacuum bagged and baked for 20 hours.

The Z91 gives SQ oriented users new possibilities for system design. There has never been a woofer available with this combination of design elements; highest magnetic energy, lowest moving mass and a 100% wire filled, excursion path length.