Shielding components from EMI/RFI... Help please

Almarg, I have heard of interconnects with the shield only connected on one end. I was not sure if that arrangement would work in this application.

Thanks again.

Sean

Sounds like the Cat6 experiment has produced uncertain results. I've already ordered shielded Cat6 from Amazon, so when it arrives I will let you know if I hear any difference. In the meantime...

I can now report that my shielding experiment has produced fantastic results. I hesitate to use the word 'fantastic,' because I don't want to diminish my credibility by overstating the facts. But the fact is that the addition of shielding has produced very impressive results.

I had an audiophile friend over who is familiar with my system and he said "It sounds like a different system." THAT might be an overstatement, but it is fair to say that the system sounds MUCH improved. Two improvements are particularly noticeable: Greater resolution and less high frequency grain and glare. The difference in these two categories is so pronounced that you can literally hear the improvements from the next room.

Here's everything I've done so far:

-Custom cut 16ga. copper plates around the Meridian G68's power supply, analog output stage, and the entire underside of the lid. All plates are grounded to the chassis.

-An aluminum/copper enclosure around the Empirical Audio reclocker. The enclosure is grounded to a dedicated ground rod under the house, and the reclocker is electrically insulated from the enclosure.

-An aluminum/copper enclosure around the Sonos. The enclosure is grounded to the dedicated ground rod, and the Sonos is electrically insulated from the enclosure.

The biggest gains were achieved by adding copper plates inside the Meridian preamp/processor. I added plates in three separate stages, and each time there was a clearly audible improvement. Apparently, in this case, more is more.

I don't know how generalizable my results are to other preamps, because my Meridian G68 is undoubtably much noisier than the typical audiophile preamp. But my G68 is also my dac, and I suspect that similar results could be achieved with other dac's or players.

It bears repeating that I am not an ideologue when it comes to shielding, as you can see in this thread. My (admittedly limited) experiences have led me to prefer unshielded or minimally shielded analog interconnects and power cords.

But digital interconnects and digital circuits are another story. For a while I've suspected that shielding most (all?) things digital is a good idea, and the results of this experiment confirm that suspicion. Of course this is a sample size of 1, so I recognize that YMMV.

Bryon

Bryoncunningham,

What's with the dedicated ground rod buried under the house?

The earth does not possess some mystical magical power that will suck, drain, RFI to it.

What you have created is a great path for a lightning strike to follow. There is a reason why all grounding electrodes of a building must be connected to one another....

Just for a test disconnect the shields from the dedicated ground rod and reconnect them to the chassis ground of the equipment. Post back your listening results.
Jim

Sounds like you made some worthwhile improvements. Your conclusions seem to support the idea of separates. I have separates in my system and some even have separate power supplies. I'm a believer.

It is interesting that with some careful shielding some integrated solutions can be improved. Makes you wonder why you don't see shielding like you have done in more high end integrated designs.

Sean - I think my results, if they can be generalized, point to the value of extensive shielding in dac's and cd players, all of which have clocks, and many of which have noisy power supplies. I agree that it's strange that you don't see extensive shielding more often. The copper for the shielding in my G68 cost me about $100. That's a very small fraction of the current $12K msrp.

Jim - The ground rod wasn't based on magical thinking. It was based on the belief that the ground for a Faraday cage should be different from the ground for the equipment inside the cage. I gather from your comments that that is incorrect.

When I installed the copper shielding inside the G68, I grounded it to the G68's chassis. The dedicated ground rod was used only for the 2 enclosures - one for the reclocker and one for the Sonos. I have disconnected the ground rod and connected the enclosures' ground cables to a conductive spot on the G68's chassis. My initial impression is that I can hear no difference between that arrangement and my previous one.

Bryon