Concept

To help understand the concept of the Pico component grounding block, it’s worth discussing again our fundamental foes, microphony and RFI/EMI.

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Firstly microphony is a problem that is so poorly understood, and generally dealt with so badly, yet it’s such a significant destroyer of performance. What happens is that certain electrical devices in the circuits of your components, such as capacitors, produce an additional signal if they are vibrated. And this unwanted signal adds to the actual signal, distorting it. But this distortion is not random, because the microphonic effect is driven by the vibration from mains transformers, vibration getting in from the air (and thus your music), and actually the shape of the signal waveform you are sending through the circuits. The result is that the distortion is directly driven by the energy in your system, and it’s in sync with those rapid changes in that energy. So this unwanted effect is directly related to level and dynamics, and the complexity of the music. It breaks down strong sounds in the mix, rolls off and smears percussion and damages phase so that imaging is poor. And it adds a resultant distortion energy that sounds very unpleasant – it’s harsh and ‘shouty’, making listening an unpleasant, fatiguing experience.

And it’s a very similar story with RFI and EMI. There’s a background noise level in all electrical signals, and that random noise can cloud the sound a little, subtly reducing transparency. But we have new problems in our modern world – things like switch mode power supplies, wi-fi and mobile phone networks have very specific signals. We also have a lot of digital processing within our components. All this processing, and all these signals, pollute your power supplies and all the grounds throughout your system. Pollute the power and the grounds and of course you pollute your signals. Now the thing about adding lots of powerful unwanted signals, even if they are at very high frequencies, is that they intermodulate with the signals that you actually want, and produce ‘products’ that you can clearly hear. These products can sound particularly nasty because they are harsh in nature and again the amount of this distortion increases with the level and complexity of your musical signals.

Now, if a system is left to suffer from these two problems (as most unfortunately do) then we end up with a poor sound, and one where no amount of component swapping will ever fix the situation (unless its Aletheia components!).

But, we have many techniques at our disposal at Vertex AQ to reduce these problems. We have mastered the principles of acoustic impedance matching to drain away vibration, and then how to distroy that vibration with destructive interference in our acoustic labyrinths. And we have clever ways in which to break down harmful high frequency electrical signals such as RFI.

The Opportunity

In any hi-fi component there are many circuits, but there are always some pretty similar characteristics to them regardless of the variations in their design. All analogue and digital circuits have power supplies feeding each element (be it something like a processing chip, or a gain circuit), and each of these elements also has a ground connection which completes the circuit and allows the power to flow through the device. And to keep everything referenced to zero volts, all these grounds are connected back to the main ground of the power supplies. And furthermore, any signal grounds on any incoming or outgoing connectors are also connected to this ground. So, all grounds are connected to each other.


But grounds are also used to dump noise. In most hi-fi designs each chip or circuit stage will have a small bypass capacitor between its supply connection and ground, or supply pin and ground pin if it’s a chip. This is so that any local noise that may have been picked up on the power line, perhaps from other parts of the circuit, gets bypassed down to ground, rather than being fed into the stage or chip. But as we said, all those grounds are connected together, and to all the other grounds in the rest of your system, room, house, neighbourhood…..

And the final piece in this story, your household Earth, or the Earth back at your sub-station, only behaves essentially like a DC Earth, its there as a safety device (50Hz or 60Hz mains is such a low frequency in ‘electrical signal’ terms). If you have a fault, and power suddenly goes and makes a case live, there’s a huge flow of current back down to Earth and your fuse or breaker blows within milliseconds of the fault. But go up in frequency, say anything above 100kHz, and there is so much impedance in the Earth wiring it’s effectively useless.

But what if we can connect something to those grounds in the core of your hi-fi and drain away that electrical noise into something designed to work at those higher frequencies? And what if we can also use all that ground wiring in those core circuits to lower vibration, and hence lower microphony exactly where your precious processing is going on. Well, we usually do have access to those grounds – unused RCA or XLR connectors are our way in!

Topology

The Pico Component Grounding Box comes with two RCA connectors on the endplate, and two cables with RCA connectors on one end and either RCA, XLR, spades or crocodile clips (you can ground racks with them too!). The cables are made using a single high-quality silver-plated OFC wire with PTFE insulation. It’s quite a thick gauge so that it acts as a good acoustic conductor. The cables are sleeved with our proprietary EMI absorptive tubing, with an outer poly braiding over. In the cable and the block itself, only the grounds are used – signal pins are not connected. Also, to prevent hum loops, the two ground lines within the module are not connected to each other.

In the module itself the ground of each socket is connected to a feed wire which enters the acoustic labyrinth, providing a low impedance acoustic route into an advanced labyrinth structure. It is here that the myriad of acoustic path lengths break down vibration with destructive interference. Also connected to this feed wire are our special methods of breaking down signal waveforms, again using the theory of destructive interference and (without wishing to give too much away) the mathematics of antenna stub theory. The whole structure is then potted in resin with passive EMI absorption incorporated.

Use And Sound Quality

The Pico Component Grounding Block is pretty simple to use. Plug it into two unused sockets, put the block on a shelf or the floor and your done. But there’s a reason why we put two connectors on the box. You can use the two lines into two different parts of your system. You might for instance find it best to use one in an unused digital output, and the other in an unused analogue output, thus cleaning up both digital and analogue areas. And you can use more than one Pico CGB of course – you might use one to treat a CD transport and DAC (using one Pico cable to each of these), then a second Pico for a spare line stage socket and power amp socket.

The sound quality improvements are usually quite significant, and they multiply if you use two or three Picos. Customers sit in disbelief at the improvement in clarity and musicality, the increase in scale and drama, the improved image depth and width, and the increase in detail. Timing and the propulsive nature of music is so much better, so your emotional connection to the artists improves dramatically.

Tonality and naturalness benefit greatly, and you are immediately aware of a big drop in bright intermodulation distortion. Customers report improved smoothness, yet with even more detail and sparkle in the treble, with a resulting drop in fatigue levels. Overall your access to your music collection is elevated. Different genres, very commercial recordings and even older poor recordings are given a new lease of life.