[MKOM]

OK...Here we go.....Electrical Isolation

I wanted to get some feedback as to how the respective membership is addressing this very important issue within their own systems.

As we evolve on a non-terrestrial communications network, such as mobile phones and or Blackberrys, the amount of RFI has increased substantially and as such, impacted Audio in a very negative manner.....to some it up....That "grunge" or "high frequency smear" that we hear is a direct result of RFI contaminating the signal path.

This is especially evident in Valve based systems....

Your feedback is greatly appreciated...

[cryotweaks]

EMI/RFI  comes from airborne sources (cell phones, wireless networks, appliances), the power grid, and exists within our own audio gear.

To thwart airborne RFI  one can use Shielded cables, and cables made of non-metallic material (Cerious tech, Cyberlight, and carbon fiber).  One can also use items like Stillpoints ERS cloth, and other shielding materials to help minimize RFI within their components.

Good power conditioning is a must these days, unless you live on the outskirts of civilization.  One also would be advised to use shielded power cables as well.

Making sure to the best of one's ability that the equipment they use has actually been designed to minimize emission of EMI/RFI is important.  But that is not a spec a manufacturer usually offers.

An EMI meter, and I think its called a "noise sniffer" (and its made by Blue Circle) can help one determine sources of EMI/RFI and help one minimize it around their audio gear.

Of course you can always build a lead lined bunker 40 feet underground and feed your system off of battery power......

I hope this is helpful.

[DonnieW]

I think you need to identify your adversary before you try to deal with it.  I put up a quick demo of what the Blackberry does and others saw it first hand at Daygloworange's place.  Based on my years in communications in the Army I can tell you it's not easy...  We're masters at suppressing (concealing) EFI, RFI and otherwise stray signals or interference - and doing so is no easy chore.  

I'd first like to hear (no pun intended) what people 'think' they are hearing, in terms of RFI/EFI, and where they think it is coming from??  I'd be more than willing to demo some sophisticated detection equipment that will enlighten many.

[Daygloworange]

DonnieW,

You'll have to bring that stuff by sometime. Sounds cool.

I haven't experimented with conditioning yet, as I don't have any alarm to do so yet. My system is pretty dead quiet. That doesn't mean that I won't look into it, however. I am seriously interested in looking into battery powered amps, don't know if that entirely makes you immune to RFI/EFI though.

Cheers

[aerius]

If I win the $27 million lottery jackpot this week, I intend to move into a fully isolated and shielded missile silo home.  It was designed to survive the EMP from a nuclear blast so I'm quite sure that all that concrete & steel will keep out RFI.  Run my own generator and I have guaranteed clean power.

Until then I make do with some isolation transformers & industrial RF/EMI filters which I picked up from the local surplus store.

[Syrah]

Hey MKOM.  I'm the guy who lives across the street from your store.

I use a Jon Risch designed Iso Trannie.  I had Dan Santoni do several mods for me, including multiple Auricaps across the line and to ground, both before and after the trannie per Paul Kaplan's great advice.

The iso trannie is in another room with an umbilical (Flavor 4 wiring) leading to a seperate box in my system room that houses 8 Hubble outlets.  Some of the outlets use inductors and some don't so that I can play with different setups.  I used the inductors that Risch recommends, but I found them to kill the dynamics on my Dodd 120s, so I switched to the same inductors that Gary Dodd uses for his IC iso trannie - that was the ticket for the Dodds.  To my surprise, even my PS Audio P300 sounds better plugged into the iso trannie and a socket that uses an inductor.

For safety sake, every box is fused and the whole thing has one big switch (before any caps) that I turn off when I'm not listening to the system - I did this to reduce cap wear and tear...

Every box in this setup is faraday shielded to ground.  I have a Noise Sniffer and this setup makes it dead quiet compared to my house line.

Maybe I'll just treat the whole room with aluminum wallpaper and ground it all.  This is called the divorce formula faraday cage - look honey, do you like what I did with the living room...

[audioferret]

If I win the $27 million lottery jackpot this week, I intend to move into a fully isolated and shielded missile silo home.  It was designed to survive the EMP from a nuclear blast so I'm quite sure that all that concrete & steel will keep out RFI.  Run my own generator and I have guaranteed clean power.

Sadly, they are selling one outside of Denver for 1.8 Million.  210 acres, three silos, miles of underground tunnels.  Yet, it is still less than a nice house in Boulder on less than one acre...

[DonnieW]

If you're in a basement (bunker) most of your interference will come by way of the mains or your own equipment (which can be mitigated by keeping components reasonably spaced apart).  Mains and cable interaction is likely the biggest pain to tame.

[DonnieW]

Sounds silly but I like to see how stores organize their components and wiring.  Do they advertise power conditioning or quality cables yet stuff 30 wires behind the rack with no sense of arrangement for interference sake??  Lot to be said about just keeping things well arranged.

[Spirit]

Sounds silly but I like to see how stores organize their components and wiring.  Do they advertise power conditioning or quality cables yet stuff 30 wires behind the rack with no sense of arrangement for interference sake??  Lot to be said about just keeping things well arranged.

You haven't been to MKOM's store.  Probably the only guy that I have met in the sales end of the business who takes this issue seriously from an audio perspective, and just from a profit slant.

[MKOM]

Hi Syrah:

Good to hear from you.

The area of RFI/EFI suppression is mission critical for us.  In my opinion and next to Mechanical Isolation, Electrical Isolation is the single most important area that has the biggest impact on any system.  It is also unfortunate that it is often taken for granted or completely overlooked.

From a retail perspective, it is far easier for most dealers promote or sell new products than educating potential clients on the benefits of addressing the RFI/EFI issue.  Having a good understanding the client environment also impacts the solution.  As such, it does become difficult in making clients aware of something that appears to be virtual rather than physical such as RFI/EFI suppression.

As mentioned before, there are many products in the marketplace ranging from most Power Bars to the most exotic & expensive Power Cords.  The fact is that they all do work.  The big question is "by how much ?"

Over the years we have had the pleasure of auditioning & living with most of them.  Based on our own criteria, it has come down to one single product that has had the largest impact, Foundation Research.

The FR line up includes the LC1 & LC2 which currently have been superseded by the new LC10, LC20 and the LC100.  I think the main reason why these products have been so effective in addressing or eliminating RFI/EFI problems is that the technology that resides within has not been designed specifically for Audio.  In fact, it was designed to be used in Ultra Sound Testing Equipment for military applications.

I could go on but all I can say is that for most listeners that have not addressed this very important issue, they have not realized the full potential or capability of their components.

At our next meeting, Mr. Ed Wolkow of Foundation Research has agreed to speak to our members on this very subject.  In the interim, and as a reminder, feel free to drop in tomorrow evening at our listening session. 

Happy Listening,

MKOM