Air coils

Air coils are the uncompromising reference: maximally linear, without distortions caused by the core. They deliver maximum impulse fidelity and particularly natural, open playback. If space and a sufficiently low DC resistance are possible, air is the first choice.

OFC Copper

• Purity: at least 99.995% Cu, often 99.999% (4N) or higher
• Feature: almost oxygen-free (typically <10 ppm)
• Result: more stable grain boundaries, less oxide formation, more uniform electron flow

Polypropylene as the Insulator

The conductor of the coil is a foil made of (Angelique) copper, silver, or (Angelique) silver-gold. Unlike enameled copper wire, for example, the foil is not coated with enamel for insulation; instead, a polypropylene film wound together with the foil conductor serves as the insulator.

Electrical strengths

• Compared to wire enamels, polypropylene has a low dielectric constant and very low dielectric losses → very low parasitic capacitance
• The polypropylene film is thicker than a typical wire enamel coating → further reduced parasitic capacitance
• A foil coil tightly wound with PP film forms an extremely solid block. The softer PP film also provides strong damping against mechanical vibrations.

Massive Metal Foil

Solid metal foil means: A real metal foil forms the electrode — not a wafer-thin coating. This provides very high, uniform conductivity along the coil, reduces field gradients and enables high current carrying capacity. The higher film weight reduces field force-related vibrations and the electrode remains stable even under impulse load. This creates a robust basis for demanding applications that transfers energy directly and in a load-stable manner — without “flickering” on the electrode side.

Tonal effects

• More pressure and control in the bass/root tone, with clearer contours instead of buzzing
• Superior at level peaks: less compression, more headroom and punch without harshness
• Cleaner transients and more stable dynamics, even with fast pulse trains
• Quieter, more ordered sound: less flicker/internal discolouration, better audibility in complex passages

Tight Tolerances

Tight tolerances in capacitance, inductance, and resistance ensure that capacitors of one type are very close together in terms of their electrical properties. In crossovers, the left and right channels therefore work virtually identically: crossover frequencies, level ratios and phase positions match closely. This is the basis for stable, precise stereo imaging and reproducible results — in series production and also after service.

Tonal Effects

• precise, stable soundstage without drifting
• Coherent overall impression: left and right channels fuse into a single, seamless whole
• characteristic sound is reliably retained even after component replacement/repair
• More stable virtual center and clearer spatial layering