79 replies to this topic

[kyrill]

Cotton wool is a very normal product, find something like this http://www.couchroll........e-250.htmlyou can manually make them more airy

yes

copper mesh or any other metallic mesh has  terrible d. conctant.>13  Also the metal damped on cloth lowers dielectric C. but as it is  so thin its negative effect on musical experience is much lesser.

 

I have compared copper mesh to metalized fabrics ( directly) wrapped around the wire and the cloth sounds much less harsh than direct* contact with copper mesh

*not against naked wire of course,

 

cotton wool has a dielectric C. of 1.5 but I assume anything (excluding metals) which beholds air in a large way ( very airy foam of sponges?) will have low D.constant as well, but here are no tables of them

 

IMPORTANT God is in the details:) ( not the devil..) Do not allow RFI or EMI leakage between 'shield'  and receptacle at the and of the wires.The receptacles must be shielded and overlap the mesh or cloth.

There are different ways to do that. A receptacle 'house' made of metal, which for dc power is rare, They are mostly plastic. So use shield paint, RFI shield fabric and wrap it around it or metal tape, or shield paint at least 3 layers as paint only attenuate 40-45 db instead of 80 of the right fabrics or mesh

Edited by kyrill, 14 March 2014 - 07:29 PM.

[SIMA66]

When you said Cotton wool, I imagined something like this:

http://www.partsconn........otton.html

 

I would appreciated if you have any links for all those "materials" used in all those steps? 

This way we can avoid any misunderstanding.

 

I'm just trying to get clearer picture and prepare my "working plan"!

 

Probably the cables will be ordered with both ends done and I will do the shielding after.

[kyrill]

Links can be found http://jplay.eu/foru........harshness/ posts # 17 and 25

 

The partsconnection cotton sleeves are very expensive cotton shoelaces, but not all shoelaces have an inner core,

They are good if you use bare OCC copper, but then it is a bit more difficult to guide multi-stranded cable through the cotton sleeves.If you use a single cable it will be a bit thick. you cannot use too thin single cable for power ( depends on wattage.) To twist two not really flexible one core cables make a very stiff DC cable.

 

There are many 'hook up wires' you can find on the internet in all qualities. best is Occ and cryo'd

to make it simple use wire with a teflon 'jacket/ Cotton sleeves are more nice to use for RC to RCA data/signal  cables, not power. as they can be thin and single and thus flexible.

[Mike Gillespie]

Just moving this thread up so it's easier to find for the guys who just bought the 3M   Guys, Please remember to post your results and thoughts on implementation here…  

[kevalin]

Below are pictures showing my trial of the AB5100S.  1. Placed on the inside door of the main breaker panel to the house (no picture). I can post if interested. Not certain if I did it correctly. There was a 6" untreated spaced at the upper door where the chart assigning switch delegation is located. This is above the main breaker switches and other switches. As I recall, just two large copper bars lay behind the cover. 2. The SLC SSD drive is mounted to Paul Pang's Aluminum brick. So I boxed in the unit on 5 sides and underneath the chassis for the 6th side. 3. RAM has it placed over the RAM cover/heat sink. Since 1 and 3 are close together, only one layer is between the two Ram chips, mounted to Ram 1. 4. over top of CPU chip and a large 10" by 10" under the motherboard (placed under the Chassis) 5. cover both sides of the flexible riser to the USB card. I am open to other suggestions. My evaluation: the sound stage is more forward, instruments are significantly even more well defined, as I would perceive as an intimate studio session. Certainly added weight to the Zuma. I also have the new Jcat card but have not installed it as I am anticipating my ATX full linear PS from Paul Hynes.  (Gosh, I am having trouble loading the pictures...ugh)

[edn4x4]

Here are a couple of pictures of my first round of adding the 3m sheets to my
audioPC.  It is a CAPS V3 lagoon with a RWA external battery.

1. I put a 7.25x7.25 inch square between the bottom of the case and the mobo and
   on the inside front panel.

 

 

2. Also on parts of the mobo I felt comfortable with.  These are marked with the green.

 



 

I have a few questions.

On the mobo I have marked in red where I would like to add some coverage, but wasnt sure if it would be ok
to do so.  The red squares labeled with the number 2 I would like to know if ok to add.

On the red square labeled number 1 is my USB card riser – any idea how to cover this??  Could I box it in
somehow?

The CPU is covered with the black heat sink – anyone know if it comes off?? or should I just cut narrow strips
and place on top of the heat sink.

The blue square labeled number 3 – what can I co with that?

Also Kyrill – you mention to tape the edges – what kind of tape  are you using – Scotch tape?
As you see Kyrill I used your sugestion to go past the legs – I may add a second layer next time I am inside.

Has anyone used the 3m inside your preamp or power amp?  I was thinking of putting some only on the mirror
sides and top where there is no air vent.

What would be the priority to components for adding the sheets:

1. audioPC/ContolPC
2. DAC
3. usb/spdif converter
4. preamp
5. amp

My initial impression I would have to say the music was more relaxed / calm (Kyrill mentions this and I
think this is a great word to describe it).
I will post more pics when I add it to other components.
Eric

 

ps – Mike now I know why there are so few pics posted…

Edited by edn4x4, 06 April 2014 - 03:54 AM.

[Mike Gillespie]

Thanks for posting.   Hey guys... Let's try to get a whole bunch more from those who have done it and heard a difference.   And even if you screwed up, put up your pix and maybe we won't repeat your mistakes.  That's just as valuable.   Thanks to all. 

[kyrill]

edn4x4 said:

Here are a couple of pictures of my first round of adding the 3m sheets to my
audioPC.  It is a CAPS V3 lagoon with a RWA external battery.

1. I put a 7.25x7.25 inch square between the bottom of the case and the mobo and
   on the inside front panel. Very good

 

2. Also on parts of the mobo I felt comfortable with.  These are marked with the green.

 

 

I have a few questions.

On the mobo I have marked in red where I would like to add some coverage, but wasnt sure if it would be ok I dont think it will  be not ok to place it somewhere, but it in practice too much can be done, softening the sound. Best is to try out and when content add more and if you stay content stop or add more until you hear you loose detail, then remove the last addition. However, every loss of harshness is a softening of the sound, but not loss of detail, you have to hear the difference with real life sounds as all of them misses this electronic induced harshness
to do so.  The red squares labeled with the number 2 I would like to know if ok to add. BE generous with adding, it is not about chips but all components, so all those smd components deserve their cover up too, just cover big parts of the mobo incluiding many components.

On the red square labeled number 1 is my USB card riser – any idea how to cover this??  Could I box it in
somehow? do you use it? if yes, box it, if no leave it untreated, if it is an open connection to outside and you dont use it, shield it with metalized cloth or other anti RFI/EMI cloth or sheets

The CPU is covered with the black heat sink – anyone know if it comes off?? or should I just cut narrow strips the sink itself protects the CPU better than the emi sheets
and place on top of the heat sink.

The blue square labeled number 3 – what can I co with that? Cover that whole part of the motherboard with one sheet over the parts you already covered, Its weight is enough to hold it, you dont need to press the glue, if you make it a bit larger so it becomes  a bit stuck between the riser and the other side, it dampens mechanical vibration a bit too


Also Kyrill – you mention to tape the edges – what kind of tape  are you using – Scotch tape? any non conductive tape, ordinary but supple plastic tape will do
As you see Kyrill I used your suggestion to go past the legs – I may add a second layer next time I am inside.

Has anyone used the 3m inside your preamp or power amp?  I was thinking of putting some only on the mirror
sides and top where there is no air vent. I have done it with good result

What would be the priority to components for adding the sheets:

1. audioPC/ContolPC             1
2. DAC                                3
3. usb/spdif converter           2
4. preamp
5. amp

My initial impression I would have to say the music was more relaxed / calm (Kyrill mentions this and I
think this is a great word to describe it).
I will post more pics when I add it to other components.
Eric

Find the clocks and cover it triple the clock is the worse transmitter of RFI

 

ps – Mike now I know why there are so few pics posted…

[kyrill]

Ok one fotoo, is from my DEQX preamp as mobo pictures are all the same and now well covered, Low right corner a taped ( 3M copper tape)  BYbee small purifier in SPDIF connection

Edited by kyrill, 06 April 2014 - 11:15 AM.

[LewinskiH01]

Kyrill, Impressive. I have so much to learn! I'm in the second group of the group buy, so don't have the 3M paper yet, but looking forward to experimenting. I see you use 3M copper tape. Is this 3M Copper Shielding Tape 1245? Which with have you found optimal? I have aluminum duct tape, but I guess that wouldn't work much, right? I also have TI mu-metal left from previous endeavors. When do you use copper and when paper, and why? At what kind of applications would mu-metal be best?

[germay0653]

kyrill said:

Ok one fotoo, is from my DEQX preamp as mobo pictures are all the same and now well covered, Low right corner a taped ( 3M copper tape)  BYbee small purifier in SPDIF connection

Wow Kyrill,  you executed an all out assault on getting rid of EMI and RFI.  Impressive that you didn't short anything out.  You must have a lot of patience!

[kyrill]

LewinskiH01 said:

Kyrill,

Impressive. I have so much to learn!

I'm in the second group of the group buy, so don't have the 3M paper yet, but looking forward to experimenting. I see you use 3M copper tape. Is this 3M Copper Shielding Tape 1245?  YES best >85 db attenuation Which with have you found optimal? They are all optimal, embossed the one I use is a bit more db effective  careful; some types have  c o n d u c t i v e adhesive

I have aluminum duct tape, but I guess that wouldn't work much, right? will work 3-5 db less effective
I also have TI mu-metal left from previous endeavors. I think they are better as they will attenuate also magnetic fields next to RFI

When do you use copper and when paper, and why? At what kind of applications would mu-metal be best?

 

All metal are have worst Dielectric constants, so I put loose soft paper (tissues or cotton balls spread out to pus metal sheets or  tapes away from sensitive components) as heat is not a issue. more necessary with cables, on the other hand a pcb is a bunch of internalized cables as well

[kyrill]

LewinskiH01 mu metal is best compared to normal metal(like) sheets or foils with abundance of magnetic fields, so near a transformer or with power lines. But stray RFI in metal enclosures and metals in components will produce stray magnetic fields. I use a cobalt version of  shielding RFI foild cloth and use that internally too. The cobalt attenuates magn. fields. but less than the supreme mu metal. But all these solutions ignore the RFI and noise already entered in the data lines. to filter them partly out, Bybee purifiers do a good job.   Germay A short is deadly, and i can's see which component is dead, That is why I use gladly paper or cloth or cotton balls (nice low D.Constant of 2) between components and metal like cloth of sheets and triple check anything

Edited by kyrill, 06 April 2014 - 04:21 PM.

[stoneman]

I've used fine mesh and copper tape to make Faraday type cages in my Audio PC (as well as using 3M dotted around and cable shielding/earthing).  Above was for the USB connectors on the front panel.  I also cut out any unused cables (mic, headphone etc) and the remaining cables have been copper taped to the case floor.

  

I made similar cages for RAM and my Lynx sound card





To avoid any chance of shorting, I used gaffa/duct tape on the bottom edges





Inspired by Adam, I have a lump of brass on the CPU - but I've gone totally overkill, it weighs nearly 4kgs /wp-content/forum-smileys/sf-surprised.gif

Was it worth it?  Yes; I think the differences are subtle be there (and I quite enjoyed the whole eccentric process).

What I'll repeat though is, shielding and grounding the DC lines to CPU, Pico and SSD had a huge positive impact, far more than 3M, brass cages etc. and really made the benefit of the LPS shine through.  It's also very cost effective.

If you're going to do any of this, do them first I say.  

cheers

Andy

[edn4x4]

Thanks again kyrill - I will give it another go adding more inside my audiopc and will post pics and comments then. Having your pics really helps to visualize what you are explaining.  I would have never guessed that you had that much material stuffed inside your DEQX! BTW - I do use the riser for my JCAT USB card.  Anything there that I can shield without shorting?  Eric

[kyrill]

wow andy, but

your pictures are too small

 

What making  net cages? every little hole is pass through for wavelengths

"

Where f = frequency in Hz, c is light velocity, and λ represents wavelength in meters. One rule of thumb often used for Faraday cages to prevent transmission is that the holes need to be no larger than 1/10 of the wavelength of the signal. So for a 3G cell phone that operates at a frequency of 2.1 GHz (2.1 * 10⁹ Hz), the wavelength = (3 * 10⁸ m/sec) / (2.1 * 10⁹ Hz) = .14 meters. Thus, for a Faraday cage to prevent this noise from entering, the holes in the cage should be smaller than .014 meters (or 1.4 cm). "(http://wiki.backyard...he_Faraday_Cage)

So for 10 gigs the holes has to be 3 mm, but 10 gigs is nothing yet. Marcin already concluded that a lot of pollution are in the micro wave and SHF band which for practical reasons is between 1 and 80 GHz. (Miltary) satelites operate between 30 and 80+GHz. So a mesh with invisible holes is the best. But with a full metallic enclosure ( not with vent holes! or functional openings…*) these freqs. are not inside. That leaves the internal generated RFI freqs. I dont know how high they are. but to be on the safe side, I prefer Faraday cages which are full metal or full metalized foil. * those high freqs do not fan out, but can only travel in a straight line unless they bounce and take a next straight line.

 

Seeing yr dedication jumping out of the the too small pictures I recommend urgently to experiment with Bybee purifiers and AVM paint /wp-content/forum-smileys/sf-cool.gif/wp-content/forum-smileys/sf-laugh.gif/wp-content/forum-smileys/sf-cool.gif

Edited by kyrill, 06 April 2014 - 05:36 PM.

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[kyrill]

edn4x4 said:

Thanks again kyrill – I will give it another go adding more inside my audiopc and will post pics and comments then.

Having your pics really helps to visualize what you are explaining.  I would have never guessed that you had that much material stuffed inside your DEQX!

BTW – I do use the riser for my JCAT USB card.  Anything there that I can shield without shorting? 

Eric

Cut the 3M Emi pieces and use plastic tape, tape the cut ends, they are conductive. not the surface of the sheets

If you use fabrics metalized wrap them in a thin plastic supple bag

And make a 3D cage around the  JCAT USB card and tape the outer side (!) not seeing the JCat USB card with metal tape or at least 3 layers of kitchen foil to reflect all  RFI reaching the wondrous Usb card. The 3M 5100s is to absorb the RFI from the card itself not bouncing back.

Edited by kyrill, 06 April 2014 - 05:45 PM.

[kyrill]

I looked better now at you beautiful cages stoneman but I see a particular disadvantage, The cage works two ways, it also prevents RFI from the shielded components to leave the cage, they bounce back to sender. So they do add noise a kind of smearing effect, unimportant for all but audiophile functions and hyper radar analysis. The cage does not dampen but reflects. To ground the cage will help  flush current but the higher the freqs, the lesser this happens to a point that grounding  has no practical effects. I would use 3M EMI abundantly inside the cages

[LewinskiH01]

What I'll repeat though is, shielding and grounding the DC lines to CPU, Pico and SSD had a huge positive impact, far more than 3M, brass cages etc. and really made the benefit of the LPS shine through.  It's also very cost effective. If you're going to do any of this, do them first I say.   cheers Andy Great work Stoneman! I guess I should start with the DC cables from my linear PSU to the server, then. Would you mind posting a picture/explanation of what you did, or what you recommend doing? Have you guys used carbon fiber fabric? I built a few carbon fiber pieces and have fabric left...I ask if usefull since it's conductive and flexible (and available to me). Great thread!

[Mike Gillespie]

Yes, Stoneman and Lewinski... and others... please explain how you did the grounding...