So far so good, but once you start adding extra components to the system the complexity of the grounding arrangements increases significantly. Once you start playing with external grounding devices, you can make that ‘exponentially’.
If/when you add a second power amp, connect it to socket two and lift the signal ground. Add a digital front-end (say – a D1.5 transport and C1.2 DAC) and you can follow the same logic, lifting both jumpers and still grounding the signal through the L1. You could plug those two units into sockets seven and eight on the QB8 or, you can provide the (often ‘noisy’ – at least in ground terms) digital components with their own distribution block and AC supply, especially if they grow extra boxes, like a T1 clock and another X1 power supply. In general, you are still going to get the best results connecting the signal ground via the L1, but as with so many things to do with system grounding, it’s a case of suck it and see… With an all CH set up, the ability to separate the signal and chassis grounds so easily, generally means that you will be better off running a single, comprehensive grounding system, assuming that you don’t run out of sockets. Use a different digital front-end, like a Wadax combination or a CEC transport driving a Lampizator, and all bets are off, with a far higher likelihood of a separated AC/grounding arrangement delivering better results.
Stepping up…
But where things get really tricky is once you start trying to apply additional, parallel grounding to the CH system. Adding a grounding device to the P1 and M1.1(s) is easy; there are chassis grounds equipped with 4mm sockets just waiting to be used. But what about the L1? It is potentially the most important unit of all, but with the jumper tying the chassis and signal grounds together, how do you attach the parallel ground? The conventional solution would be to go through an unused input or output socket – although as a dual-mono circuit, it’s better to run a cable to both the left and right channel circuit boards, doubling the number of ground cables you need and the number of connections for them on your ground box.
A better and more cost effective solution comes in the shape of a smart little adaptor produced by Ron Buffington of Liquid Hi-Fi in the US. As a dealer for CH, Nordost and CAD, he has come across this problem on a number of occasions. His solution? A hand-built jumper constructed from Nordost’s OEM hook-up wire that offers an additional Z-plug to act as a ground connection point. In essence, this works exactly like the jumper supplied by CH with the L1 – but due to the hollow construction of that extra Z-plug, you’ve also got an extra 4mm socket to connect the line-stage to a parallel ground.
What is even more interesting is that the Buffington jumper sounds significantly better than the stock item, with a noticeable reduction in grain and a new crispness and vitality to micro dynamic range and dynamic discrimination. Musicians and instruments are more clearly focussed, more dimensional and more immediate, moving you that much closer to the performers and their performance. Once external grounds enter the equation, the Buffington jumper with a single ground wire is even better, stretching its advantage over the stock jumper and a pair of ground wires, each dedicated to a single channel. That’s using the same type of ground cable in both instances. Cost differential means that if you use the Buffington jumper you can also upgrade to a better ground wire and likely still save money…
