iFi Audio DC Blocker / DC Blocker+

IEC filter that stops DC on the mains and transformer hum

The iFi Audio DC Blocker is a small in-line filter that plugs into the amplifier's IEC inlet: it blocks the DC component present on the mains, the cause of the mechanical hum of large toroidal transformers. ZERO DC Block technology stops up to 1,200 mV of DC without affecting EMI shielding or equipment safety.

It fits between the power cord and the component's inlet, with nothing to adjust. The compact body does not obstruct nearby sockets; the IEC connectors are hospital grade and the materials are UL94-V0 flame resistant.

Two versions: 4 A DC Blocker and 10 A DC Blocker+

The standard DC Blocker works from 90 to 240 V with a continuous current rating of 4 A (maximum over 7 A) and suits amplifiers up to 880 W at 220 V. It measures 68 x 37 x 32 mm and weighs 63 g.

The DC Blocker+ is designed for high-power equipment: 90 to 250 V, 10 A continuous (14 A maximum) and amplifiers up to 2,200 W at 220 V, for a weight of 80 g.