E-Core Inductor (Transformer Core Inductor)

The transformer core inductor works with an E-shaped core made of Feron sheet metal. Compared with the I-core, considerably more Feron is available in the magnetic circuit. The field-strengthening effect is substantially higher: for a given inductance, less winding effort is required – and this is precisely where the central advantage of this design comes from.

In practice this means: at high inductance, E-core inductors achieve a comparatively much lower RDC than I-core inductors. This is particularly valuable when an inductor is used in the bass or lower midrange, where the series resistance directly determines efficiency, damping and control. At the same time – thanks to Feron – the signal remains very clean even under load, because fundamental distortion caused by remagnetization is kept extremely low and saturation distortion does not come into play even at party levels or in PA applications.

The E-core shape also has design consequences: these inductors are typically not mounted on the circuit board but fixed directly to the enclosure. There are two reasons for this: first, E-core inductors for high inductance and low resistance are often larger and heavier; second, mechanical mounting in the enclosure (rigid, decoupled, well-defined) is often the better way to keep the entire crossover permanently stable and magnetically clean.

Field of application

E-core inductors are the right choice when low RDC is to be combined with high inductance and the inductor does not necessarily have to be board-mounted. They are the “classic powerhouse” within the Feron family: highly efficient in the magnetic circuit, very strong in the ratio of inductance to resistance.

Acoustic properties

• Extreme control and power handling thanks to very low series resistance
• Very calm, clean reproduction even under dynamics and load
• Particularly strong in the bass/lower midrange, where RDC is directly audible
• Maximum authority at high currents