The Pico Component Grounding Block (CGB) has been a huge success since its launch in November 2013. Already, many happy customers have been thrilled by the improvements one or more CGBs have brought to their systems. But how they produce such big changes to sound quality raises some serious issues about hi-fi component engineering, system building and indeed our understanding and perceptions about the theories and design priorities for hi-fi – from the bottom up!

First I’ll go over the background again, how Pico CGBs are used and how they work.

The Pico CGB has two RCA input sockets and two leads, to give two ground connection points. The signal pins are not used, only the Earth connection. Using the two cables, you connect them into your system, into unused line level or unused digital connectors, and the other end of the leads into the Pico box of course.

In essence, the Pico connections to the grounds in your system provide an efficient route out for vibration and RFI. The cables are deliberately highly acoustically conductive to allow vibration to travel, then the connectors in the Pico box take that vibration through into an acoustic labyrinth, to break down the vibration in the box using destructive interference.

Also the cables and the terminations in the box are designed to act like ‘lossy antennae’ with a special lossy termination and EMI/RFI absorption treatment on the cables and in the box.

If you want to know more, see the main Pico CGB page here.

And what does a pico do to your components, and to sound quality? Well, lowering the RFI and broadband sonic vibration on the internal system grounds greatly lowers noise and intermodulation in all those active and passive circuits that use Earth as a bypass ground or a ground reference. The results are invariably profound – have a read of some recent customer testimonials for some great insight into the improvements.

Buts lets step back and look at the bigger implications of what’s happening.

We traditionally put a system together with boxes, interconnects and power leads. We think about the individual sound quality of each component, each cable and so-on.

Look deeper though. You use a pico CGB in your system and it gives a significant improvement in performance without, in the conventional sense, any change to the signal chain whatsoever. So how, actually, can we make sound quality decisions about hifi components and cables in the conventional way at all?

First, take interconnects, and the whole process of connecting an output connector to an input connector between two boxes with an interconnect. We paint a mental picture about the signal – “this interconnect is carrying my precious signal from point A to point B”. We try a few different cables, and we think they sound a bit different, so they must be slightly modifying the signal in some way, right? But what if they are behaving differently on their grounds? What if they have an unknown RFI behaviour on the ground and they are altering the amount of RFI in the grounds of both boxes?

And what if those cables have unknown acoustic conduction properties and are altering the amount of microphony in the grounds and signal circuits of both boxes? So is each cable you are testing actually transferring different amounts of vibration and RFI between the boxes? How much of that accounts for the changes in sound we are hearing?

Then consider the scenario doing AB comparisons of some power amps say. You don’t know how the grounding in each amp is designed, you don’t know if there are any effective anti-RFI and anti-microphony treatments in these power amps. You try one, then the next. You notice differences in the performance of your system and put it down to “how good the amplifying circuits in each amp are” or, “how good a match are they to my speakers.” But, here we go again, after the experience with a Pico CGB, how do you now know that the changes are not actually a performance change in your pre-amp, just because it’s seeing different RFI and vibration characteristics up the leads from these different power amps?

So the picos force us to think very differently about how components and leads interact with each other, and indeed how they are designed on a fundamental level.

If you examine carefully the review on the DAC 1 by Alan Sircom, you will see how he discusses at length that the DAC improves the performance of the whole system even when the DAC itself is not playing, but just because it’s plugged into the system. It’s because in essence, that DAC has quite a few Pico’s in there and they are effecting the rest of the system just by the DAC being plugged in.

And there is one other fundamental question to now raise too. Mains conditioning.

So often we are led to believe that for ‘mains conditioning’ we need one box, one big box to block all that RFI. Well, Apart from the risk that such an approach can be very microphonic, this certainly cannot be relied upon as the whole RFI solution. We know that now, in light of how much improvement the Picos bring,

We’ve always said at vertex, use the systematic approach, use multiple shunt filters on the mains, use vertex mains leads to prevent vibration travelling around your mains loom, and if you do require anything inline, make sure it is not horribly microphonic, eg the Aletheia psus. John Cheadle has just written a post here about the problems with transformers, which can be a significant contributor to these issues.

The Picos are a total game changer in a system. They bring a huge reduction in the noise floor, intermodulation and time domain smearing. But they are reducing those effects where they are happening – in the core of the circuitry of your system. We have a fundamental principal at vertex. “Identify the damaging artefacts, create a route to take those artefacts away from those places where they can do damage to your signal, then break them down in another location”. It is now clear to us that this is a critical engineering principle for the production of good HiFi.

Share Button