Audiolab DC Block Direct Current Blocker

Audiolab DC Block Direct Current Blocker

The Audiolab DC Block Direct Current Blocker has been designed to improve the quality of AC electricity that feeds our audio and AV systems.

Mains electricity fundamentally influences the audio signal as it passes through a system, from source to amp to speakers. The mains supply in a typical dwelling is subject to interference induced by a range of issues, causing the AC waveform to distort before it reaches each component.

Audiolab DC Block Direct Current Block creates noise in the audio signal, degrading sound quality – a situation that worsens as the electrical devices we use in our homes increase.

Overview: DC mains supply

One common issue is ‘DC on the mains’ – a problem well known to affect the performance of audio equipment, especially amplifiers. I

In theory, the main electricity we obtain from the sockets in our homes should be pure AC, with a perfectly symmetrical sine wave alternating between positive and negative phases.

However, the presence of ‘asymmetrical loads’ – myriad household devices that use the AC energy available in the mains cycle unevenly, from dimmer switches to kitchen appliances to computer power supplies – causes the waveform to become offset, resulting in the presence of DC voltage on the AC supply.

Overview: DC Voltage

The AC transformers commonly used in home audio equipment cannot tolerate the presence of significant levels of DC voltage without being compromised.

Less than 500mV of DC – typical in an average household electricity supply – can be sufficient to cause toroidal transformers of the kind often found in amplifiers to become saturated, which adversely affects sonic performance and may cause audible mechanical vibration.

By blocking, or canceling, the DC voltage found within the AC mains supply, the Audiolab DC Block Direct Current Blocker corrects the DC offset and rebalances the main sine wave (see illustration above).

But tackling ‘DC on the mains’ is not the only benefit delivered by this dual-action device – it also contains a high-performance audio class filtering circuit that removes RFI/EMI contaminants from the mains supply.

Audiolab DC Block Direct Current Blocker is effective in reducing both differential-mode noise (exacerbated by cheap switch-mode power supplies used by many home appliances) and common-mode noise (aggravated by airborne interference from phones, Wi-Fi networks, and Bluetooth).

This combination of technologies ensures that the Audiolab DC Block Direct Current Blocker does more than solve the problem of transformer saturation caused by DC on the mains; it also helps to unlock the sonic potential of any audio component to which it is connected.

The noise floor drops and the sound gains greater focus, with reduced grain, improved clarity, better-defined bass, and ‘airier’ treble.

Overview: Simple setup

Using the Audiolab DC Block Direct Current Blocker is simple – plug its output into the IEC power socket of an audio/AV component, then connect its input to a mains socket (both cables are provided).

The device is designed for use with a single audio or AV system component – Audiolab recommends that if one DC Block is purchased, it should be used with the integrated amp or power amp component within the user’s system to obtain the greatest benefit from the DC-blocking technology.

If desired, further units may be purchased to use with other electronics in the system – preamps, source components, and so on. With each additional Audiolab DC Block Direct Current Blocker, further incremental improvements in overall system performance can be expected.