Voice Coil Technology
The P.Audio Design low-frequency transducers utilize either Square Wire Technology™ or Inside Only™ technology. Each technology is used in specific models to provide a very high degree of optimization. The specific technology, either Square Wire Technology or Inside Only, is used based on the specific intended application for each model. This approach is central to many P.Audio Design custom transducers. Various technologies are employed to optimize specific performance parameters based on the desired end-use of the product.
Square Wire Technology(SWT)™
A typical two layer, round wire voice coil is shown in Figure 1. This voice coil geometry is not a very efficient design. The areas between the winding use up physical space and limit the amount of wire available to produce the electro-magnetic field needed for an efficient energy conversion. These areas are shown in Figure 2. The red arrow shows the areas where the round geometry prevents electrical conductor from contributing to the overall conversion of electrical to acoustic energy. In addition to this inefficient use of space, the two layer design shows the outside layer in direct contact with the air in the magnetic gap, but the inside layer is trapped between the outside layer and the coil former. The position of the inside layer does not allow efficient heat transfer so the inner layer does not cool as well as the outside layer. This lack of efficient cooling acts to put additional stress on the adhesive systems of the assembly and reduces the loudspeakers reliability. The additional heating also acts to reduce the electrical current flow into the loudspeaker and reduces system efficiency and output.
The red arrow in Figure 2 shows the areas where the wire geometry prevents conductor from improving the overall loudspeaker efficiency. The round shape of the wire does not allow for a high density of conductor in the magnetic gap of the loudspeaker.
Inside Only Voice Coils™
When transducer bandwidth is an important parameter, such as with the 12 inch and 15 inch models, P.Audio Design utilizes Inside Only technology. This technology is licensed from One Systems™ and provides excellent system cooling and reduced power compression but also allows for a very low total moving mass. The reduced moving mass improves high frequency system bandwidth but maintains an excellent path for the transfer of thermal energy.