Ferrite HP3616 – Ceramic High-Performance Ferrite for Audio

Ferrite is a ceramic, sintered magnetic material based on iron oxide with additives. The decisive advantage of ferrite lies in its extremely high electrical resistivity, i.e. a very high specific electrical resistance. As a result, there are practically no eddy current losses – even at increasing frequency. For audio applications this means: very clean behavior in the small-signal range.

HP3616 is a specially selected ferrite that differs significantly from simple standard ferrites. Its coercive field strength is very low, so remagnetization takes place quickly and with little distortion. Especially around the zero crossing of the signal – i.e. where hysteresis-related fundamental distortion arises – HP3616 remains exceptionally clean. This is exactly where its strength lies.

The high magnetic permeability of ferrite makes it possible to realize large inductances with few turns. This allows compact inductors with low R_DC to be built. This property makes HP3616 ideal for correction networks, equalization branches and midrange applications in which precision, timing and clean small-signal performance are more important than maximum current-handling capability.

The limiting factor for the use of ferrite is its saturation flux density. It is significantly lower than that of iron or silicon iron. If the core is driven hard, it can reach saturation relatively early, causing the inductance to collapse. This effect does not occur gradually but comparatively abruptly, and then leads to clearly audible distortion. For this reason, ferrite – even in high-quality form – is not the first choice for high continuous currents in the bass.

Sonically, HP3616 is very precise, fast and clear. In correctly dimensioned applications, the core practically “disappears” from the sound. Many developers even prefer ferrite over air-core coils here, because the lower R_DC it makes possible stabilizes the filter response.

Classification: HP3616 is the specialist for clean small-signal work. Wherever precision matters more than raw power, this ferrite plays to its strengths.

Ferrite Core Shapes

Ferrite H-core – Maximum precision in minimal space.

Ferrite in the H-core combines high magnetic efficiency with very low fundamental distortion in the small-signal range. Thanks to the closed magnetic circuit, compact designs with low R_DC are possible. This combination works extremely cleanly as long as the currents remain moderate. At high levels, however, it reaches the saturation limit sooner than other core variants. It is ideal for correction networks, equalizers and precise midrange applications.

Ferrite P-core – Precision with additional reserve.

The P-core gives the ferrite considerably more current reserve than the H-core. The small-signal cleanliness of the ferrite is retained, while saturation sets in later. In return, more turns are required, which results in a higher R_DC for the same wire cross-section. This combination is more robust against level peaks while remaining compact. It is suitable for midrange sections with higher dynamics or a slight transition into the lower midrange.