Copper Sleeve over IEC

There has been several threads on AA about putting a 1 1/2" copper union (coupler) over the IEC on the CD Player, Preamp, Amp.

Well I tried it...

Anyone else give it a try?
Since there has not been any response to this thread thus far, I thought I would add some more information in the hopes of catching some AudioGonners attention.

This really is a very good tweak at a very cheap cost.
It was posted on AA along with a video from "You tube" from Marantz on using the copper union on thier CD player's IEC.

The claim is that the power cables are shielded but the IEC ends are plastic and are not shielded.


Well. I tried the 1 1/2" copper sleeve (called a plumbimg union or coupler) on my CD player and it worked great ! You simply slide the copper fitting over the IEC ,then plug the IEC in and slide the copper union up tight to the players chassis.
The highs and bass became more extended and defined and the soundstage images become more precise.

If one sleeve is great, more should be even greater. right?

Well no, too much copper is not a good thing.

I tried another couple of the 1 1/2" copper sleeves on my Preamp and Amp IEC's with not so good results.
Then I tried some 3/4" sleeves on my XLR's not so good.

So, I stuck with just the copper sleeve over the IEC on the CD player.

What I noticed was with the copper sleeves on the Amp and the interconnects was that the sound became deadened.

Perhaps it has to do more with the type of power cable that was used on my Amp (Synergistic Hologram A) and my interconnects (Synergistic Apex, Presicion Ref) that caused the sound to deaden with the copper sleeves.
Or perhaps just the digital is prone to the ill effects of EMI/RF?grounding, I dont know.

But using the copper 1 1/2" sleeve on the digital IEC is in my opinion the best place for these sleeves.

Hope this helps.
Thanks. Sounds intriguing. Certainly inexpensive enough to give it a try. I'll let you know how it works on my Bryston BCD1.
I've tried the Stillpoints ERS cloth wrapped around various IEC's in my equipment, serves same function. Sometimes beneficial, other times deadens the sound, not using any in present setup.
Where's the YouTube video ?

I typed in Marantz SA-7S1 per Dr. Phil at Alcoholics Anonymous ..........
Try this link for the You Tube video
Tried the sleeve last night and was astounded at the improvement just as Ozzy described. More articulate bass, more precise imaging and deeper soundstage. Gotta get one for my HT/secondary system now.
Thanks for the great suggestion!
Interesting video, which shows the application of multiple tweaks (not just the copper sleeve). Have you tried using a homemade ground wire as seen in the video? It looks as if he used a regular 3-pin plug, but removed the positive and neutral pins – leaving only the ground pin; then he simply screwed the other end (bare wire) to the back of the CD player. Additionally, he noted that you should load each CD twice before playback. Anyone try all three of these tweaks in combination as seen on the video?
My CD player already has a 3 prong outlet, so I havent tried that suggestion.
Nor have I tried the double reading trick, although that one is easy to do anytime.
My CD player already has a 3 prong outlet, so I havent tried that suggestion.
Nor have I tried the double reading trick, although that one is easy to do anytime.

I guess I didn't catch the fact that the Marantz did not already utilize a grounded connection - I thought the tweak was in addition to... Strange that a highend unit like that doesn't utilze a grounded connection.
2chnlben, Yeah, I thought so too. Jgiacalo, Glad the simple tweak worked for you.

Too bad I didnt put a fancy label and a blue LED on it.
I could have made millions...
Good news Ozzy and tweakers,

Went to Lowes, bought a 1-1/2"x 1-1/4" copper coupler-reducer stock #89479 (smaller end fits closer to the IEC end plugging into component) $3.47 YTMV (your taxes may vary)

Slipped it over the end of the Shunyata King Cobra going to my CEC transport and WOW.

Micro-dynamics, clarity, depth, I'm going FULL-BROKE and buy 4 more (preamp, dac, mono amps ?)

Thanks Ozzy (and Lowes) these could sell for $50.00 a pop and be a deal, price/performance ratio is incredible.
Rx8man, Glad you like it. It really works quite good on digital.
Let me know how it works on your Preamp, Amp.
Thanks for the tip. I tried but couldn't find the item on their website. Can you send link if not too much to ask?
I have placed the copper union piece at the MarantzSA-11S1 cd player, at the Art Audio Px-25, and at the IEC connection of my PS Audio Premier Power Regenerator. I noticed good results. There is a on going good discussion at the Tweek forum of Audio Asylum of using copper and how it works.. Carbon Fiber Tubes may also work to good effect.
If you buy the copper pieces at Lowes or Home Depoit you can return them for a refund. Cost is about $4.50 each
Ozzy and Tweakers :

I added another copper sleeve on the preamp cord, with an additional increase in dynamics.

A good idea would be to gage the coupler size to your specific power cord end(s) so they are not a sloppy fit.

I might go with 1-1/4" straight across, instead of the reducer from
1-1/2" (provides a closer fit yet)

This is a cheap, awesome tweak, takes seconds to install, is reversible and refundable.

The beauty is, increased musicality with no discernable downsides (in my system)

I'm going to try the other end of each power cord going into the Hydra next.

Lowe's website does not list these specifcally, go to the plumbing dept, look through the bins and size on the barcode sticker.
Ok, you guys got me all hyped up now and I'm gonna give it a shot sometimes this weekend.

- Just for the record, can anyone email me some pictures?

-Do I still get full benefit if my power cord is not shielded.

THanks in advance and the part number is a big help too.
Another update: Add another Copper sleeve to the AC (on the male end) power cord on your CD player.

This sleeve along with the other sleeve over the IEC end of the AC power cord to your CD player really adds dynamics!
Bass is stronger, treble and midrange better defined and smoother and the soundstage becomes more stable.
The best one word to describe this sound is SOLID!

I still have had no luck with the copper sleeves on my Preamp and Amp. With sleeves on this equipment,they sort of suck the life out of the sound. Maybe, because both of these pieces are Pass Labs equipment.Pass may be doing something already inside the equipment that the extra copper sleeves become too much.

But the additional copper Sleeve on the power cord to the CD player is a must!

I put copper sleeves on the IEC ends for the transport, dac, preamp,
mono amps & twist-lock P/C to the Hydra, the sound in my rig is fabulous.

This tweak did much more of an improvement than changing tubes or power cords, about a good 15%-18% total for less than $30.00 !
Glad to hear the tweak is working out for you.
One question, what brand are your power cables and are they shielded?
hi, I am wondering if you grounded the copper sleave . if not it is realy not shielding anything. I bet what you are hearing is michanical dampaning of the iec, which could result in better sound. happy listening, chrissain
Now I haven't had the time to audibly check what happens after installation but what I can report is that I use a portable AM radio tuned just off a station (to get static) and the polymer or plastic housings on IEC and male ends of my power cords are noisy and do exhibit less noise when the copper is in place. Not dead silent but less noise. I do have 1 power cord whose terminations are finished in aluminium and they are quiet even without the copper on them. One of my cords must not be insulated (its a 3 wire braided cord) which is noisy all along the cord itself so I don't think having copper over the ends will do much but I may be wrong.

While not yet proven by myself my opinion is that this tweak may be most effective on insulated power cords.
Chrissain, Why dont you try it for yourself and then you decide?
It will cost less than $5 for one, or under $10 bucks for two.
Try 2 on your power cable to your CD player one on each end.
Rgd. Actually I'm thinking that the copper sleeve at the ends is the only place shielding is important.
If you can eliminate the nasties going into your components they will have less garbage to work with.
First off let me say I have no electrical background and I am not DIY (soldering and the like) kind of guy either so my thoughts are worth what you are paying for them...

I can see how the copper sleeve could stop airborne nasties from entering in at the IEC opening but a noisy cord like the one I have when the copper sleeve is in place isn't necessarily stopping anything from entering. It may only be acting as a shield on outbound noise from being detected. The noise traveling along the cable may be going right into the unit and the noise is less audible at the copper sleeve because its blocking it from coming out. It may still be blocking anything more from going in (which is a good thing) but it isn't necessarily blocking this noise from going into the unit. Something that may block something from entering may be just as effective blocking something from coming out as well. I still think insulated cords may be the best cord to use this tweak on.

Well thats the extent of my technical BS and I defer this to people more knowledgeable in these matters...
Yes briefly (but without listening for any audible changes) and as I said earlier I "measured" the outcome using my home made device (AM radio) that in fact when the copper sleeve is in place it reduces the noise at the terminations.

But my point is that while the copper sleeve reduces this "noise" it may not be negating it - it may only stop it from escaping and that's why I don't hear it...

Maybe my home made tool is inadequate for this exercise?

I'm all for tweaks, especially cheap ones, but if the design or desired outcome of this tweak is to stop "crap" from entering whatever component its being used on I still say the best cord is an insulated cord because if an uninsulated cord picks up anything through the cord itself it could be transmitted along the cord and into the gear and the copper sleeve would not stop this from occurring as far as I can see. If the design is to ensure that no power escapes at the terminations (although I don't know if that's possible or even a negative consequence) then I guess it works as it is quiet for my test as well.

If anyone out there has the proper tool to measure this they should try and do so with an uninsulated cord as well. If you hear noise all along the cord and then its silent at the IEC and with the copper in place it may very well be because the copper blocks you from hearing it but it doesn't prove its "killing" it off.

Maybe I am just missing the point or not expressing myself clearly enough...
You may mistaken EMI and RFI. While RFI MUST need a ground wire to disepate its energy... like the lightning rod, the MAGNETIC energy /force can be controled by creating barriers, distant, or demagnectized equipments. Hooking up a ground wire to demagnitize the magnet energy is not an effective tool.

I totally agree with you. How the copper coupler can take in effect right at the female plug while my whole entire power cord if it isn't shielded and fully exposed?
But I think this tweak makes sense and has a potential to improve sound. Everytime we can control either very much, alot , or just a little of EMI and/or RFI, it is a benefit to perfection the audio sound.
Disregard the fact that many of our power cables are not fully shielded, if this copper coupler tweak actually works in theory, then if I may, I can exagerate it as the power conditioner working concept. Which means it can analize then stablize the un-filtered and un-stabled electricity (current, voltage, and hz) from the main source ( elect. Company). See? All the power lines are not shielded but we, as audiophiles, still working hard to find ways to go around it.
In this hobby, I PERSONALLY admire to ones that continuosly
finding/hunting for ways to maximize their mid-end systems than others who spend $20K to $50K for a pair of speakers and knowing nothing about technicality.
So,like Ozzy's been screaming all week, give it a try!!!
Cyclonicman, I was wondering that too.

Even the big name CD manufactures should be including or have a built in/out copper sleeve.
I know my Cary CD player has a copper base and a copper shroud around the transport, wonder why they they never thought to provide a copper built in/out sleeve.

Perhaps it is because most Audiophiles use there own power cord with the Cary Equipment and the IEC has been a standard item on Audio equipment for years.

So they (Cary Audio and all others) probably did'nt think outside the box. (pun intended)
I'd like to suggest that those with DIY skills, solder the connectors to both ends of your power cords. Often times, the screws will loosen even on high end connectors. The results are audible and I always use solder only connectors on the IEC ends. The plugs I modify, removing all screws and any magnetic material.
hi, i think that it is easy to underestimate the importance of vibration controll on michanical connections. the copper sleave is heavy and dense, and i would bet that a large portion of what you are hearing is michanical dampening of the plug . just a hunch, happy listening, chrissain
one more tweek, for all those of you that can open the iec or male plugs on your powercords, get the clear silicone caulk at home depot and fill your connectors, the improvement is worthwhile . loose and undampend mechanical connections are a source of noise, this is very well documented. see what nelson pass has to say about cables. one more cheap tweak to try, good luck and happy listening ! chrissain

I might have some clearance problems at the AC ends due to very close spacing on the back of the Hydra and size of the Shunyata cords.

I'll try and give it a shot, without scraping the lettering or heatshrinks on a 2K P/C !

For a nice look, I used Goo-Gone to remove the adhesives on the outside of the sleeves, then used a Scotch-Brite pad to debur the ends and polish the inside and outside for a nice looking finish, rinsed-em in soapy warm water to clean-em up.

This tweak should stay here for us, if a manufacturer catches wind, the price of a P/C would double, in this economy we need real deals.
The Reference models from are eliminating /reducing EMI right where it was being generated, the Toroid transformers. The INSIDE images from the website show beautiful craftsmanship of the Reference models and how well the Toroid transformers being covered. Let’s compare them with ones that are “naked” from cheaper MArantz models....

The Halo models from have diff route to reduce EMI. They use thick and solid wall plates to corner up the transformer then move some of the electrical components and wiring that they think would be effect the most to the other side of the plates and away from the transformers.
Other companies may have diff ways to control EMI, but so far I like the way Marantz do theirs most.

That makes sense, show no harm and doesn't cost much to do. Sounds promising.
I'm going to get the copper connectors and give it a try. Sounds very promising!

One question: anybody tried a copper sleeve throughout the whole power cord (for unshielded PC)? I have a stock PC on my Rotel RCD-1072 As you can imagine, it's a cheap, ungrounded PC. So I'm thinking of using some thin-wall copper piping (relatively flevible) + the copper connectors on the ends. And also grounding the chassis like in the Marantz video.

Any thoughts?

Rx8man, I understand what you mean, my Synergistic PowerCell has pretty close plug outlet arrangement too.
Just dont try to fit 2 copper sleeves on the same outlet or next to each other, that will never work.
I was really only concerned with my Cary CD player and Tascam CD recorder. I moved those so they were not next to each other and was able to use the sleeve and plug them in.

Chrissain, not sure if I have the nerve to insert glue inside the Synergistic Hologram D powercord. I may try it first on a lesser (in $$$) cord first. Thanks for the tip.

Nasaman, Marantz seems to have an interest with proper shielding,good for them. Heck,just the fact that they released the video on the copper sleeves shows there on the right track.
Funny though that they didnt provide a ground wire to thier $$$ CD Player...
Lewinskih01, Personaly, I think most of the improvement is from treating the ends of the digital power cords.

Just for some info, I priced 2" copper I think it was 8 feet long but maybe it was 10.
It cost $88 bucks !!! When your done it will probably bend like Virtual Dynamics cables do...

Perhaps try some copper flashing that they use on roofs.

But hey, give it a go, and let us know how it sounds.
ZU audio does in fact do this on their top power cables, not copper but custom cut aluminum housings. And I believe they are also filled internally with an Epoxy such as mentioned above with filling the IEC with Silicone, because you cannot take them apart even removing the screws so there definitely glued down and feel full not hollow, Zu does this with their RCA connections and XLR as well. They are the quietest I have heard.
03-17-09: Rx8man
Good news Ozzy and tweakers,

Went to Lowes, bought a 1-1/2"x 1-1/4" copper coupler-reducer stock #89479 (smaller end fits closer to the IEC end plugging into component) $3.47 YTMV (your taxes may vary)

you lucky so-so Rx8man! I went to Home Depot & Lowes yesterday & NEITHER had any copper couplers larger than 1"! :( I showed them the stock # at Lowes & the fellow came back & said that it did not exist in their system! Where else can I buy a copper coupler? I need atleast 1- 1/4" for the IEC & 1-1/2" for the male AC plug.
Bombaywalla , Man that is too bad. Perhaps you can try on line with a plumbing supply house?

Try this place
Or try this

At this place you can get all kinds of copper fittings, including reducers to 1 1/4".
For those ordering I decided to take a Watt gate / marinco IEC and AC plug end to my nearby Ace hardware... Warning NOT ALL THE copper fittings are going to fit, Problem is that ONLY the fittings with a 1.25" ID(Inner Diameter)will work, most of them have a 1.25" OD (outer diameter)

All of the straight fittings I found had only a 1.25" outer diameter so they did not fit over the body of the plug, the 1.5" are WAY too big and you would need to fill the gap with a bunch of tape or something to beef up the connectors size and or Tape it on in place if you don't want it falling off. The best I found was a Coupler made with one end as a 1.25" inner diameter, and it was then reduced to a 1.25" outer diameter… And use a pipe cutter to just cut it at the rounded reducer shoulder and throw the bad half away.. This fits super snug and has a professional finish.
Thanks for the info. The largest plugs I have,(and they are pretty large),allow the 1 1/2" copper couplers to go over it. It does'nt fall off either on the IEC or the AC end.

I suppose if you had a real big AC plug with a very thin cable, then you would need something to hold it on. One of the posters suggestions was to use some sticky back foam insulation on the cable before sliding the copper sleeve over.But anyway you get there is good.

Can you post or send a picture of your finished product?
If you need to expand the coupler take it to muffler shop and have it expanded a bit..... They didn't charge me to do mine.

I LOVE your Scintillas !!

Try McMaster Carr or cruz to a local hardware store if you strike out
at Home Dumbpot or Lowesly.

Take your P/C with you and gage it on the spot, that's what I did.
You can skip the double sided tape and just use a bead of Blu tack on each side of the Body and it will slip on tight and the blu tack will just ball up underneath and keep it super solid without vibration.. also this way it is removable with a little force to slide it back off, that is if you have the correct 1.25" ID copper pipe to finish it well without it just hanging off rattling around like on that marantz video.