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In all of my tweaking for the past year, one of the things I have failed to address is RF/EMI pollution entering my gear through unused RCA jacks. I am using my receiver as a pre-amp and haven't wanted to spend the $300.00 it's going to take to get the job done because I didn't think the problem was that bad, and was afraid that the cost-benefit wasn't reasonable. What was I thinking! As a dyed-in-the-wool cheapskate, I was looking for cost-effective alternatives when I decided to just place paper tape over the jacks. It worked to some extent, so I decided to place a hematite bead over each inlet with a dab of silicon gel to see if it added to the benefit. It did- and to a considerable degree. However, I found that the sound got darker as I added more beads. I have hematite all over my gear(outside the electronics) and this is the first time I have noticed a degradation in sound quality with the addition of more beads. I had some unused amethyst beads laying around from previous experiments, so I thought I'd try them. EUREKA!! The sound immediatley got brighter and louder.
I have gotten improvement in every area of the aduio spectrum. Bass is tighter and more resilient. Highs are better defined and more musical. Attacks and decays improved. Better space betweem instruments. Triangle strikes livelier and cymbal shimmers more pronounced. Much better percussion in all areas and more musical presence.
For less than five cents per jack, this has been a tremendous tweak for me. I hope it works as well in your system.
kendo
Follow Ups:
Means that the case is a poor rf shield, as it is no longer earthed (the give away is when the cable is two core)
Simply Earthing the box would turn it into a faraday screen, and does some really funky things to the sound.
Owen
Browsing around on ebay I noticed that amethyst beads seem to come in a lot of colors, is one particular color considered best for audio?
You can do a similar thing with a shorting plug in the RCA jack. I have actually measured the effect using a spectrum analyzer and it is quite apparent, especially if you have your gear in a noisy environment. I use the Hi-Fi Tuning gold shorties because they look nice on my gear, but you can make them from any old cheap RCA plug by simply shorting the two wires together with a 10-100 ohm resistor.
Unfortunately, paper is transparent to RF, although I don't doubt you heard an improvement. It's just that the improvement couldn't have been due to a reduction in RFI. The mystery deepens.
nt
I have read several discussions by manufactures on trying to keep RF out of their products. The Blowtorch Preamp is a good example. Thick CNC aluminum enclosure with right angle shelving for the removable panel. Most sheet metal chassis are not very good at keeping it out.
are loads of devices designed for RFI rejection in a chassis. A simple google search will reveal many companies specializing in such application, particularly for military use. The simplest means of sealing a chassis is to use conductive gaskets, employing a conductive mesh. I have purchased surplus military gear with such shielding. IT is quite commonplace in the military componentry.
Stu
Would lining a chassis with copper wire screen be affective?
the copper screen would do very little. It is the seams where you need the shielding.
A copper screen lining would reduce the eddy currents generated by the electrical pathways. Counterpoint had an excellent white paper as to why they would copper plate their component chassis even though they would paint the copper over for cosmetics. RFI was not a factor for them.
Stu
nt
I found an interesting site that sells several varieties of RF blocking fabric. It is a finer weave which would be an advantage. You need to imagine submerging your component under water and how water would enter the enclosure. That gives an idea of how RF can enter.
Now I can get a picture , of what you mean.
Can you share a link to the website, if possible.
Thanks!
here you go
nt
The issue is complete surrounds with no openings bigger than the wavelengths you are trying to shield. That's why microwaves can be "safe" with see through glass doors: the mesh screen in the glass has holes smaller than the microwaves.
So now I get more of an understanding on how using a condutive gasket could help. I will have to do some reading on Farraday Cages.
Thanks!
some more effective than others
I'm not knocking you; I'm cheering you on.
A few of us have been telling you that ferrous materials - hematite included - can have deleterious sonic effects. You've found some benefit until now, so nobody wants to tell you that you're wrong if it's truly working for you. But I think you've now seen that there is indeed a downside, maybe just not as bad as some ferrites can be.
So you're catching on to the silicate crystal tweak. That seems to work very well for those of us who've tried it in various places, with no downside.
In fact, amethyst is one of the more consistently pleasing RFI tweaks for me in my and my friends' systems, particularly treated amethyst. And you don't have to spend a fortune on it, either.
So now maybe you'll consider trying amethyst instead of the hematite all over your system?????
Are you treating them yourself? If so can you say what do you (or others) treat them with?
Don't knock ferrites. Ferrite clamps are excellent RFI chokes and absorbers, and at $1-2 each they are a great value as well. I have them on the power cords of every appliance in my home, and on the Romex cables coming from them to the breaker box. Really helps to clean up the RF pollution and minimize what gets back into my dedicated audio circuit.
I don't happen to use ferrites, though you are absolutely correct in your assertion about them as inexpesive RFI filters.
Years ago, and in successive waves, AA inmates have posted first positive and then not so positive reviews on ferrites. Seems they are trickier in some locations and you can easily overdo them - according to the others - so I never bothered. Same with ERS cloth, which also works in moderation in some places, but not in others.
So far crystals have shown me no downside at all, and that's been the reports I've seen from other posters and friends. Only one I know has ever claimed to reach a limit for crystal filtering, and he had more of them than I could ever consider in my own home.
I'm still experimenting with the ferrites on the cables of my stereo system, but putting them on all the other power cables in the house is a no brainer to me based on their low cost. Even better than filtering out the RFI is not letting it get into your system in the first place, so the ferrites are on the power cords or hard-wired cables of my two refrigerators, washer, stove, toaster oven, dishwasher, sump pump, burglar alarm, water treatment system, central air conditioner, internet router, TVs, cable boxes, wireless phone chargers, cell phone chargers, DVD player, etc. After placement of all the ferrites there was a noticable increase in detail, clarity and 3-D imaging in my stereo system, even though I already use a PS Audio Power Plant Premier AC regenerator for all my components.
As far as the stereo equipment, I have found a positive effect by placing one on the umbilical cable between my tube preamp power supply and preamp units. Clamping two onto the dedicated 12 gauge Romex where it enters the listening room and at the breaker box end also yielded an improvement in sound. Placing them on my shielded power cords does not seem to have any effect.
Yup, they really work. And should be quite 'safe' at the sources as you are doing.
I doubt that many AAers think they don't work, rather they are probably concerned that they may have a negative effect also. And I suppose they might depending upon which ones you use and where you use them. No surprise there, nails are like that also, they work pretty well in walls, not so good in tires. But ferrites (aka Z-beads) are magic bullets when doing EMI work, both for investigation and often for the cure. Stir in 3M shielding tape, tinfoil and a spectrum analyzer and you have the EMI engineer's toolbox.
As far as using them directly on your stereo system, well it all depends on the problems and implementations of the system. I've got them on every speaker cable for instance because I had a problem with a local ham transmitter years ago and haven't bothered to remove them even though he has since ditched the beam. There's a case where the signal is well balanced so it doesn't see the bead but incoming RFI is mostly longitudinal and sees their full permeability and loss tangent. All to the good in my book. Interconnects and power cords are shakier because they both tend to have at least some longitudinal signal component. Try and see is the name of the game since so much depends on how the gear is implemented and what the local RF environment is like. I think you are right on course.
Rick
I too use ferrites on all other components plugged into my power grid, excepting the actual audio components. It certainly cuts down on the RF noise generated by such things as lamps and other household appliances.
I came across the need when I started using a 1/2 HP compressor for my air bearing arm. Despite being placed on a totally separate breaker, every time the compressor kicked on I hear an unpleasant thump in the main system. No amount of filtering of the main system could eliminate that thump, until I placed a simple PLC on the compressor line itself. That cured any noise and brought forth the issue of filtering every thing else on the power grid: more expensive, but more effective.
Stu
I got a few strings of amethyst beads that I've soaked in Purex fabric softener. Where are they best used? I have Alan Maher cbfs in the usual places and cardas caps over the rca jacks on the back of my pre amp. Now what?
Power supply components: transformers, rectifiers, capacitors.
Near tubes if you have tube gear.
On plug inlets, power conditioners, outlets.
Try placing them in various locations near speakers. They helped near my woofers and tweeters.
Breaker box, but you probably have the CBFs there anyway.
You might want to try out different crystals. They each have somewhat different characters: quartz, topaz, aqua aura, and tourmalines (but not black). You might want to compare them with and without the fabric softener. My least favorite is crystal is quartz, but I still have some in my breaker box and near my phono step-up transformers where it works well. The others that I listed all perform well. I've also got a chunk of amethyst above my power amp's power transformer and it's doing beneficial things.
I put eight QR8 quartz resonators on top of one speaker and it sounded like a kazoo--a really horrible sound, but just one QR8 improved the sound stage. In this case the distortion from the crystals was unmistakable. In other cases, I'm less sure about the source--maybe worn tubes, but I removed about half of my rock pile and didn't notice any deleterious effects.
You may find it interesting that tourmaline becomes a negative ion generators when heated up. Placing them on devices which require a heat sink may be the ticket, and it certainly seems to work slightly better in my experience.
Stu
What was your negative there?
It has a high iron content which may have something to do with it.
There are probably a dozen places you can put the CBFs or your treated crystals. And some inmates say that it's hard to get too many of them, so you can double up too.
It's a matter of experimenting as to where they do the job for you in your system.
If you're only using the CBFs at the breaker box and at the outlets, next place I found great for them and crystals is top and bottom over the transformers in your gear - amp, pre, CDP, etc. You can put them in or on power strips. They seem to work around the terminations of power cords and in the middle, possibly at other nodes. And you can always try something similar to the original poster here by using them on the terminations of your ICs. At least one inmate reports using them well on speakers.
Read up what others have said. Not just here in Tweaks, but in Iso as well, as some of the original posts were redirected there when I guess the moderators thought they were too way out there.
I really don't know about your fabric softener treatment as I don't use that. I assume if it has any impact it's due to the static treating properties, but wouldn't know.
YMMV.
Is this OVER the paper or did you remove the paper tape and place this directly on the outlet?
Or one bead per inlet, two per plug with the silicone completely covering the inlet slots?
Must be fairly easy to remove if you replaced the hematite with the amethyst.
You've tried this in all your available unused outlets and found there to be a cumulative effect?
Thanks for posting!
" Once this was all Black Plasma and Imagination." -Michael McClure
Musetap, yes I placed paper tape over the inlet, then siliconed one bead over the tape per inlet. I wanted to be able to reverse the tweak if it didn't prove effective. On longer series of inlets, I got lazy and just taped a string of beads over the holes. I found the effect cumulative as I added more beads.
Bartc, thank you for your encouragement. I have posted that I have tried both hematite and amethyst and found both pleasing with the hematite being more dynamic and the amethyst being smoother in my system. Right now, I like the combination of both, better than either one alone. I think that your system is probably more resolving than mine and that might be the difference in our experience. Good chance that I will end up in your court.
Geoffkait, thanks so much for the insight. I don't have any ideas right now, but I'll bet you do. Any hints for starters?
I had forgotten about soaking the beads in fabric softner. Thanks for posting the reminder.
kendo
Try amethyst and hematite on glass doors or windows.
Cheers
N/T
" Once this was all Black Plasma and Imagination." -Michael McClure
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