High purity copper winding, High temperature polyimide former.

The RMS power ratings represent the maximum long life, continuous power input a drive unit can handle. These ratings are largely dependent on the speaker’s ability to deal with thermal heat in the voice coil. When power is applied to a voice coil, a very small percentage of the amplifiers output (only 1.0% to 3.0%) is converted into acoustic pressure.

This leaves a very high redundant energy level (97.0% to 99.0%) which is converted into thermal energy. There is an energy limit for all voice coils before thermal overload and ultimately fusing occurs.

Aluminium wound voice coil on slit ringed aluminium former.

Theoretically, with all things being equal, a 300 watt voice coil can last more than 100 years if run at only 30% of its thermal power handling. The very same 300 watt voice coil will last in theory, 30+ years at 70% of thermal ability with all things being equal.

Now if the thermal limit is always reached at 100% the voice coils life span is reduced once again by a variable factor to 10 to 5 years in theory.

Teflon coated copper voice coil on a black anodized former.

At 1000% of the voice coils thermal limit, it would fuse in 60 seconds.Voice coils are basically fuse wires and have a maximum current flow ability, exceeding its ability is not wise.

These factors depend on many other variables such as amplification and music applied and time sustained per session. This gives us some idea of the cycle duty and life expectancy of a voice coil. All

Motorola 32 bit Processor driven coil winder.

other cosmetic parts can be damaged and the sound will only be effected in a minimal manner, but when the voice coil is damaged, this is a downward spiral from which it will not recover. All Shadow Works power ratings are rated at 50% of thermal capacity, typically underrated for self preservation and assured longevity. It is very easy to give a rating of 100% or even 200% of maximum power ability. However, that is not recommended for long term listing or use and will lead to rapid damage to the voice coil reducing its life span.

The surface area of the coil is the most important area for the heat dissipation that lowers coil temperature. The larger the surface area of the coil the better thermal dissipation is achieved. In general, this thermal capability is independent of its sensitivity rating or power rating

Our latest addition to our factory is a state of the art voice coil winder which uses Embedded - Motorola 32 bit Processor technology for accuracy which no human hand can match. With Electro Guide technology this produces the most accurate, consistent voice coil available in the world today.