Whitepaper

DALI A/S [phone]
www.dali-speakers.com
7
With every product launch over the last years DALI
engineers have managed to put a little extra engine
power into the drivers at any given price point.
This is all for the benefit of uncompressed sound
reproduction, even during very dynamic passages
in the music.
In the case of ZENSOR the voice coil development
related to the woofers was a piece of engineering in
itself. We needed a high B/L product (force factor)
for a powerful and controlled bass reproduction
in a small enclosure. At the same time a smooth
and detailed midrange reproduction was crucial to
separate the speaker from any competition.
The 4-layer voice coil used in the ZENSOR 1 boosts
the B/L product by a solid 17% compared to the
more commonly used 2-layer voice coils.
And worth remembering is also: A 17% higher B/L
product reduces the electrical Q of the woofer with
27%. The result is a significant improvement in
control of the entire moving system.
While a 4-layer voice coil is effective for a high
force factor, the higher moving mass will often
present a problem for the midrange response. Thus
voice reproduction would be impaired.
Our solution for minimizing the weight was to apply
a light copper clad aluminium wire. This rather
costly solution applies an aluminium core and a
thin-walled outer copper tube.
Combining the high conductivity/weight ratio of
aluminium (205% the value of copper) with the
superior contact resistance properties and better
mechanical strength of copper, we get a light-
weight voice coil with high conductivity capable of
handling high peak signal levels.
The result is seriously improved bass control, well-
controlled reproduction of micro details and great
transient capabilities.
The ZENSOR VOKAL woofers feature an extra, reversed
magnet on the backside of the magnet system. This
is done for two purposes; to increase the B/L-product,
and to reduce the magnetic stray field.
The 4-layer light-weight voice coil design is applied to create a high motor force, enabling both powerful and precise
sound reproduction.
On the ZENSOR 1 the need for a high B/L-product was
especially important in order to maintain superior control of
the woofer in this limited cabinet volume. Therefore an extra
magnet has been added to the motor of the ZENSOR 1 woofer.