Regulated Linear PSU for Virgin Superhub

Please note this is a power supply NOT the superhub itself.

It is well documented that the supplier wall wart type switch mode power supply injects interfereance into the mains supply to your home, this can have an adverse effect on sound quality. To get the best possible sound quality from your computer audio it makes sense to investigate every area for possible improvement. One often overlooked area is the hub or router that provises your wired or wireless internet, in this instance the Virgin Media Superhub which the owner of this website currently uses.

MCRU have supplied 100’s of regulated linear power supply’s worldwide for a huge variety of hi-fi  equipment, the power supply’s have been awarded 5 star reviews purely on performance so we know they work as intended, the basic principal is to provide as clean a mains supply to your equipment as possible and thus reduce mains interferance, the supplied smps that comes with a lot of hi-fi does more harm than good, we know this by the 100’s of satisfied customers who now use our regulated linear power supplies, in other words ditch the switch!

The Virgin Superhub is powered by such a device, the dreaded wall wart smps. Removing this and fitting a fully regulated linear power supply will be another step in the right direction for optimum sound quality if you are using the superhub to pipe music through your house using various methods.

Fitted with an audiophile quality DC mains plug from renowned Japanese high end manufacturer Oyaide, the MCRU/LDA power supply is a fit and forget device, it is built in the UK by an engineer who is also a keen audiophile, up-grades to further improve it can be added at the order stage, although it will provide excellent performance in it’s standard configuration.

Below is the technical explanation behind the design.

When thinking of regulation, it’s worth remembering the Roman god Janus. Who was the god of gateways, and was a two faced god looking in both directions. Likewise a good voltage regulator is required to look in both directions at once. From one direction you have the mains supply, with the ever increasing noise, distortion and random variation that exists on our household mains supply. In the other direction you have the device you are supplying power to. The load will be asking constantly varying current, and the job of the regulator will be to ignore the varying load and to supply a rock steady voltage that ignores the changing load.

To ask a single regulator to perform both tasks means that it can not do either as well as it could. We don’t ask our regulators to be two faced, we split the two functions into two separate regulators and put them both where they can do the best job.

The first regulator is close to the mains supply, its job is to take the incoming mains and convert it into a low(ish) noise DC supply, and to isolate the mess that is our household power lines from what follows. In most power supplies on the market, the output of the first stage would be directly connected to the load device, and that would certainly be an improvement over the supplies that most manufactures provide. But we can do better by adding the other face of Janus to the system.

The second regulator is supplied with a clean low noise supply, and its job is to handle the changing demands of the load. To do that, it needs to be as close to the load as possible. So we remove the second regulator from the main box, and place it close to the load, both electrically and physically, that removes it from the noise and interference of the mains supply, and allows it to spend its time looking towards the load. Typical commercial voltage regulator chips are general purpose devices, but are not quiet enough for the task on hand, so the second regulator uses a bespoke regulator based on a low noise multi stage filtered voltage reference, a low noise error amplifier and a high current low resistance mosfet. To allow it to handle the changing load it also needs to supply current on demand, so all the remaining space in the second regulator is filled with low impedance capacitors to act as a local energy source.

Using the two stages of regulator, we achieve a noise floor equal or better than most battery supplies, and a effective source resistance of the order of 0.02 ohm (and the short cable run to the load avoids increasing this valve by adding copper where its not needed, and the use of a discrete regulator design allows that tiny value to be maintained way above frequency any audio device operates at.

Please note we also build PSU’s for turntables, NAS drives, gigabit switchers, and many more items, please enquire.