"cpo" wrote in message
. ..
would it be possible to solve the problem for the need of a huge
magnet by using an electromagnet instead of a permanent one.
obviously this would use up more power, but the strenght of your
magnet would be variable, and it would be relatively inexspensive


No, electromagnets still suffer from core saturation.

The new approach to super woofer design is to use a pot core lined with
Neodymium magnets. Through finite element analysis, the flux density
throughout the gap can be made uniform over several inches.

New voice coil technology deals with heat and power compression issues by
utilizing:

Black body radiation
Extreme forced air ventilation
More efficient transfer of electric current to electro-motive power by
keeping the coil in the magnetic field at all times.
Anodized surfaces of voice coil instead of laquer insulation, enabling
operation above 500ºF without damage.

These and other emerging technology have allowed drivers of a given size to
move the same volumes of air as four or more commercially mass-produced
drivers of the same diameter, with the benefit of reducing the number of
cabinets needed to cover a given venue.

--
Take care,

Mark & Mary Ann Weiss

www.basspig.com The Bass Pig's Lair

Business sites at:
www.mwcomms.com
www.adventuresinanimemusic.com
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