Mains electricity, crucial to your audio systems, can often be disrupted by various interferences, distorting the AC waveform, and reducing audio quality. ‘DC on the mains’ is a common problem, particularly with amplifiers.

Although household outlets are intended to deliver pure AC power, a range of your home appliances—from lighting controls to home appliances power supplies—create ‘asymmetrical loads’, resulting in DC voltage on the AC supply.

When a small amount of DC voltage from the mains reaches the transformer, it can cause ‘saturation’, leading the transformer to produce a significant and persistent humming sound. You can hear it when you bring your ear close to or next to the chassis.

The DC Blocker+ is a smart device that, when you place it at the IEC (the rear power inlet), prevents DC from getting into the amplifier, thus eliminating transformer hum.