Russ Andrews DC Blocker
5 out of 5
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- Eliminates degrading DC
- Audiograde components throughout
- 1500 watt capacity
- Inline device designed to use with a single component
- Multi-layer composition PCB
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Russ Andrews DC Blocker
We believe this is by far the highest-specified DC blocker on the market.
One of the key issues with the application of a DC blocker it that it has to sit ‘in-line’ with the power - unlike all our other filters and mains conditioners, which are parallel designs. This inevitably raises impedance, which goes a long way to explaining some of the potential negative effects we mention below (see 'The Solution').
So, to ensure minimum impact on mains impedance and maximum filtering capability, the design of every element of the Russ Andrews DC Blocker has been carefully considered, and the circuit design features components specifically chosen for use in audio applications.
Our DC Blocker is designed to solve a specific problem of DC (Direct Current) on your domestic mains supply. DC can be in the form of an audible transformer buzz, or sit in the background, potentially degrading sound quality. But what is 'DC on the mains'?
What is DC on the mains?
In a perfect world, the domestic power supply to your system should be a pure AC feed. However, along with common mode and differential mode mains noise - addressed by our range of mains conditioners - small amounts of DC current can often find their way into components. This is due to the presence of other domestic electrical devices in the home which, due to their design and/or age, can add DC onto your AC line.
The Problem
Let’s assume that the waveform of the AC voltage supplying your system is a perfect sine wave. It isn't actually - contrary to most explanations of DC blockers out there, if you look at the waveform on an oscilloscope (via a transformer) it looks awful. But, for the moment, let’s assume it is a perfectly clean and symmetrical sine wave.
Now, if you were to feed that into a component containing a toroidal transformer, assuming it is a perfect sine wave, there would be no issues. However, as we’ve just stated, it’s not at all uncommon to have small amounts of DC present. The problem is that many components with a linear power supply (which use a toroidal transformer to ‘step down’ AC voltage) do not react well to this, as the DC interferes with the magnetic field and causes mechanical vibration as a result.
This is most acute in integrated or power amplifiers which use a large toroidal transformer and can have a very low resistance to DC. Even a very small amount - 500mV or lower, which is not uncommon in an average UK supply - can saturate the core and create quite noticeable mechanical vibration (buzz) in the windings as a result.
The Solution
Sadly, the solution is also the problem. All the DC blockers we have tested - and there are many of them - have lowered the buzzing but at the expense of sapping musicality and dynamics from the music. So, before you do anything, our advice is to consider the following:
However, if you have a more constant buzzing which is interfering with your enjoyment of the music, we now have a high-quality, low-impact solution: The Russ Andrews DC Blocker.
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Specifications
- Inline device designed to use with a single component
- 1500 watt capacity – plug in any component with a power requirement up to 1500 watts
- Custom-designed PCB featuring 5mm wide, 4oz pure copper tracks. It is also a two-layer design (tracks are duplicated top and bottom of the board) to ensure a good solid low resistance connection and improved current handling capability.
- A 6.3A internal slow blow fuse fitted for safety (SuperFuse™ option)
- Kimber Kaps™ for additional smoothing of the mains supply
- Two, large capacity 10000uF capacitors for superior current handling
- KIMBER KABLE® TCX internal wiring
- Six 10A, high-current Vishay diodes providing DC blocking voltage of up to 1.5V
- Robust, 6mm thick, custom ABS enclosure
- 10A IEC input
- 13A UltraSocket™ mains output
- Dimensions: (WxHxD): 102mm x 90mm x 222mm / Weight: 0.8kg
Money Back Guarantee
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Don't forget! We are so confident in the performance of this product that it is covered by our 60 Day Home Trial with Money Back Guarantee. Buy the product and if you're not completely satisfied, you can return it within 2 months for a refund. For full details click here.
Customer Reviews
Overall product rating
5 / 5
5 / 5
reviewed by Mark
29 Jul 2024
Yes, I recommend this product.
"Absolutely Killed Buzzing & Humming From Amplifier"
My Meridian surround amp started buzzing so loudly it became unbearable. The Russ Andrews team assured me the problem was DC current on the mains and recommended the DC blocker.Firstly I tried running it from the wall socket to a powerblock feeding ALL of my components, but the results were patchy.
Positioning it after the powerblock, filtering ONLY the Meridian amp (as recommended in the instructions) it worked like a dream. No more buzzing (at all!!) & with no obvious degrading of sound quality.
Excellent product if you have DC causing a buzzing/humming issue from a component.