I have found similar results using diamond. Big improvements. Industrial diamond dust. I was actually thinking of REMOVING unused inputs.

Bugs can crawl in there and then your sound can get, well, kinda bug'y! Best to close up all openings in equipment to prevent all these evils from entering.

RG

I guess the audio business is finally exposing the scams, and not letting fraud being sold as legit products. It's about time. Industry brilliance in audio breakthroughs, always come from the small business genius. I know having an opening unused allows one to get things they don't want to happen. Plug it with this guys' incredible products. When in doubt plug it. Waiting for the "review" and high praise from a Stereophile shill.

I use both Cardas caps and other less expensive caps and have not heard any change in any system I have them in...That said, I have also not heard any problem so, at the least, I keep dust out of the connectors.

I found some of those shiny rubber caps at Radio shack to keep the dust out of the inputs. An 8 pk. sold for $5.99.

geoffkait wrote:

soulful.terrain wrote:

I found some of those shiny rubber caps at Radio shack to keep the dust out of the inputs. An 8 pk. sold for $5.99.

The adventurous type, eh?

:-)

I went crazy and mixed red and black covers. radical eh? lol!

Of course you must terminate the input with a termination load that has an impeadance equal to the input impeadance.

cyclebrain wrote:

Of course you must terminate the input with a termination load that has an impeadance equal to the input impeadance.

These caps are non-shorting, they do not provide any termination.

[img]http://www.cardas.com/images/products/rca-caps.jpg[/img]
How much do they cost? If it's more than $0.50 each it's a ripoff.

Oh noes! RF is "leaking" into my amplimifiers, wot should I doooooo?

For those of you who do not understand Radio Frequency energy, here's a quick exploration of RF as it pertains to an open, chassis mount RCA connector and a circuit not designed to pass RF energy.

The inner conductor of a female RCA chassis mount connector is in the region of 10 to 20mm. I have one on the bench that measures 18mm. This short antenna has a full wave frequency of 16.655136556 GHz. That's Giga with a G father DaDa. Any amp/equipment designer who had attended audio design 101 at college would know to add a filter to any audio input that would effectively short any stray RF to ground. Absolutely basic kids stuff. Depending on the input impedance of the circuit, this value will be in the Pf to Nf range.
Even without a cap, you'd have to question the likely sensitivity of an audio amplifier circuit to frequencies in the GHz range. My estimation would be that the amount of energy required to affect an audio amplifier input at the GHz range would be very significant and not in the order of a few pico volts of stray RF.

In conclusion, another BS product from a BS business in a BS industry (high end hi fi)Adding rubies or amethysts or pre-chewed gum to these caps will not decrease the BS quotient, in fact it amplifies it!

P.S Sorry to haunt these forums with science and engineering again but I needed a fix...

I always figured any effect would be cumulative...the protection to a single connector might be too small to hear but when everything is capped, perhaps on very good systems, an improvement might be heard. I cannot hear any change on my systems, but I use them as dust covers anyway. My problem with the product is in the price. A lot of companies sell identical caps (a tad less massive and perhaps not as pretty but serving the same purpose) for a fraction of price. That is what 75% of my caps are.

That is the result with most tweaks. They do very little by themselves but when combined with other changes, DO result in audible change, at least in my system.

Could be right...I have no idea. All I know is that a lot of folk claim an audible effect, one that I do not hear in my gear. Either they are all wrong or my system is not refined enough. Of course, I also own a Shaki stone, that sat on my old Jolida amp for a decade with perhaps a placebo effect BUT, when I parked it on my current amps, I get an edge to the sound..Is it real or not? Who knows but it is not sitting on my amp any longer.

geoffkait wrote:

Do you really think the raft of folks out there using Cardas Caps on open inputs/outputs are all deluding themselves? Do you think this the full-blown Placebo Effect in action? I don't expect the average audiophile on the street to come up with the explanation for why covering the open jacks improves the sound. That would be asking too much.

The short answer is "yes" they are deluding themselves. The ideomotor effect is alive and well. Covering open/unused RCA connectors with paper is simply laughable as a solution to stray RF or any other electromagnetic energy. Even signals coming from Pluto. Adding semiprecious stones does not make it any less comedic.
BTW, the length of the inner conductor on a chassis mount RCA connector makes it an ideal antenna for GHz frequencies and as RF goes out to 100GHz, 16GHz is well within the RF spectrum.

Geoff haven't you found that declaring every post that contradicts or disagrees with you as a "straw man" has got a bit old? Especially when it doesn't fit the argument?

No?

All of these tweaks have one thing in common, the listener is aware that they have been put in place. Simple as that. The ideomotor effect has been studied and proven to be a factor in many illusory situations. I think audiophiles would provide a peak group to study the effect actually.

P.S Thanks so much for the irrelevant song lyrics.

Many preamps turn off the unused inputs , ( Levinson , Ayre , ect ) I was wondering if the caps would still help , anyone try this ?

:-)

RG

You suggest caps on TV's or disconnnected equipment in the same room make a difference in sound yet you have nothing but personal insults for those of us who suggest a cap in yo ass will do the same thing!

Pathetic!

RG

Let's review the claims.

It was presented that Cardas Caps put on unused RCA inputs is claimed to reduce radio frequency interference from entering those inputs. This is a claim to be tested or confirmed, or a hypothesis if you want to call it that.

People who have used Cardas Caps, as well as other things on those unused inputs report hearing an "improvement" in the sound. Other report no audible difference.

Was the claimed "improvement" proven in some way as an improvement, or was it a just an audible difference? Was there truly an audible difference, or is someone fooling themselves? I have not seen evidence posted here to support that claim of audible improvement, other than opinion. Opinions are welcome, so lets move beyond that to find an explanation.

If this was truly audible, where is the link from the audibility to RFI? (recall who claimed the connection - the manufacturer of the product) So far I have not seen any evidence to show that the claimed audibility is linked to RFI in these posts.

Assuming that the audible difference is really there. If the science does not support the RFI explanation, then we must look elsewhere for a more reasonable explanation, and conclude that RFI may not be the issue.

Basically, either the audible difference is there (look for explanations other than RFI), or it's not there (then we're done).

I was simply analyzing what was written by you regarding what you related from the "AA" source and the "OP" who heard an improvement. I did not say you made the claim - only the claim was made. Each of the points I made was dissecting the path to a possible explanation. I know you were questioning the explanation offered so far in your original post.

If someone uses paper on the inputs and reports hearing a difference, then yes, it seems likely that RF is not the culprit.

It sounds intriguing if a significant difference is audible. I only asked where the connection to RF is, or has that been ruled out as the cause of audibility (or inaudibility, for those who report a null result)?

Inquiry is a good means to get to an explanation. I thought there was more details from whomever has tried this tweak. Apparently there is very limited details, judging from the original post.

Regarding the tweaks, of course any given tweak will not sound the same or have the same effect on every system. I do think that the same tweak will have the same 'type' of effect, perhaps to different degrees or even somewhat different 'character' in each system. But the tweak should have similar 'properties' (for lack of a better word) in many systems

If a tweak does not produce an audible difference, the conclusion is NOT that the tweak does not work, but rather that the tweak did not produce a difference in that particular system when used in that particular way. This also does NOT support the hypothesis that the tweak 'works'. It may actually work, but the test did not demonstrate it. So negative results are just as important as positive results. Either way, we're still back at trying to find a good explanation, as apparently it's not likely to be RF.

I use Cardas Caps on all unused RCA openings.  My speakers have EVS ground enhancers installed.  My amp has a Premium HiFiTuning fuse installed.  My solid state CD player goes through a tube buffer with a Phillips JAN 6922 (because it sounds better than other 6922's I've tried).  My IC's have networks, as well as two of my PC's.  My other PC's have a DBS pack on them.  I use wood platforms under my gear and speakers, with isolation cones for the speakers and Mapleshade brass heavyfeet under the CD and a brass weight on top for stability.  I replaced my pre/amp jumpers on my integrated with a networked IC.  My setup now sounds superior to many systems I've owned or heard with price tags in the high 6 figures!  Bottom line is that an engineer can sometimes have their head so far up their own "Oscilloscope", that they couldn't hear an improvement in sound from one piece of gear or tweak to another if their degree(s) depended on it.  Science and art MUST and DO coexist....science is afterall, God's artistry made apparent.  Everything is not known, nor will it ever be.....ours is but to wonder, experiment and try to set the mysteries free.  In other words, use your damn ears.

Lots of little changes = a big improvement...

It makes me horny....grrrrrrr baby.  Grrrreat that is:O)

...But I bought a few of these things a while back for an integrated amp with maybe 6 extra RCAs open. Wasn't sure if it made any diffrence, but at least no dust gets in, and I bought the cheaper caps so it wasn't that much money. My TV and surround receiver together of course have about 50 open inputs so I could see this being an issue. Anyway, a month ago the cable guy comes to deal with some signal loss issues and put in a line amp in our basement for the cable signal. When he was done I was shocked to see him pull out a bag of generic input caps and insert them over all the the open line jacks!

I guess I figured if these did anything at all it'd still be in the "audiophile" realm for perfectionists, but when I ask he was like "Oh yeah, these help with stray RF getting into the system." like everyone knows. So maybe it's more real after all, becasue I've never known Comcast to do anything that cost extra money just for fun; far from it. Maybe I should try Geoff's tin foil idea on all those RCAs in teh home theter setup.

Music Direct sells $2.00 versions of the Cardas Caps for years, and they keep dust out just fine. 

Cardas YouTube video, left to your interpretation: https://www.youtube.com/watch?v=KFciL0qjqu0

Concerned about RF? Try a Faraday cage around the entire system. Not as pretty, but there is actually some science behind it. I try to imagine the marketing campaign by Cardas for their $10K Faraday cage! Delicious!