Sheet 'LEAD' For Shielding Hifi

[Dan Osib]

What do people here think about the idea of lining the inside of CD Players, amplifiers etc with pure lead sheets to block various forms of interference? Would it work do you think? I know not to use it near anything magnetic like a torroidal transformer because lead is an ANTI-MAGNET.

 

[Tosh]

I know not to use it near anything magnetic like a torroidal transformer because lead is an ANTI-MAGNET.

Alchemists also thought they "knew" certain things, but they were just delusional with greed for gold....

 

[Dan Osib]

Alchemists also thought they "knew" certain things, but they were just delusional with greed for gold....

Here is where I got the information about lead being an anti-magnet or dia-magnet which is what I meant or should have said............ http://uk.ask.com/question/is-lead-magnetic

 

[Gordon Gray]

Dan,

I'm glad there's another "rogue" out there.

I just installed flexible lead strips with an adhesive backing on the "ribs" of my bass drivers. Science is that vibration causes heat and the lead strips absorb heat thereby reducing driver vibration.

I like what I'm hearing since the minor surgery.

GG

 

[Brad225]

I had thought about the same thing Dan, just never got around to trying it.
I also had thought about laminating it between two pieces of MDF for speaker boxes to help dampen them. I don't have a clue if either would do anything but why not.

Careful Gordon, based on some of the cable discussions of late, some one might tell you you heard a difference because you thought you would

 

[Brian Walsh]

What do people here think about the idea of lining the inside of CD Players, amplifiers etc with pure lead sheets to block various forms of interference? Would it work do you think? I know not to use it near anything magnetic like a torroidal transformer because lead is an ANTI-MAGNET.

I can't speak about lead, but copper sheet can be useful for grounding everything together, which also provides a level of shielding. I suggest lead is best used for weight and for mechanical damping of resonances. But it's possible for the use of lead to cause the sound to be lifeless, just as you should be careful about putting Sorbothane under things.

 

[Gordon Gray]

Brad,

I have no issue with that assertion. Got thru that about 30 years ago.

GG

 

[|Tch0rT|]

I just installed flexible lead strips with an adhesive backing on the "ribs" of my bass drivers. Science is that vibration causes heat and the lead strips absorb heat thereby reducing driver vibration.

By "ribs" do you mean the spoke like part of the woofer basket or the "ribs" some speakers have on the cones? I'm guessing you mean on the basket. I know some people like to experiment by adding mass to woofers.

Either way you should be careful due to the fumes the adhesive gives off could damage the woofer surround depending on the material.

 

[Bernard]

Careful Gordon, based on some of the cable discussions of late, some one might tell you you heard a difference because you thought you would

And let's not start about magic dots

Gordon is in good company on this forum. At least once a year we get a know-it-all newbie (sometimes slide rule toting) who tells us we are all wrong. Mercifully they leave, hopefully with a massive headache.

 

[Speedskater]

Back in the old days before environmental concerns eliminated the practice, thin sheet lead was used in the walls of recording and broadcast studios for acoustical purposes. But unless your interference problem is X-ray, then other materials are more effective. At very low frequencies mu-metal is best, at higher Hz sheet steel and at radio frequencies very thin copper or aluminum are good.

 

[Dan Osib]

Back in the old days before environmental concerns eliminated the practice, thin sheet lead was used in the walls of recording and broadcast studios for acoustical purposes. But unless your interference problem is X-ray, then other materials are more effective. At very low frequencies mu-metal is best, at higher Hz sheet steel and at radio frequencies very thin copper or aluminum are good.

Lead is supposed to completely block out RF INTERFERENCE/RADIO SIGNALS so isn't that a plus for hifi? And it will do this even without it being grounded. Doesn't that sound like a dream come true for us hifi boys?
Now that lots of people are going down the computer audio route using internet streamers etc I bet that LEAD sheets will come in very handy when installed inside our media streamers/computer equipment etc. After all ''RF'' is the biggest killer in this area of hifi.

 

[Gordon Gray]

Tch, I guess the proper term is "spokes", which connect the magnet with the basket / driver assembly.

Brian, I had read about a 70hz bump in the 116 frequency response and, in my room, it was definitely audible. The lead straps, made and not advertised by Mapleshade, seems to have addressed the issue quite well.

Dan, besides RFI, I consider vibration induced distortion to also be a significant factor in marginal sound.

Bernard, I do offer a bottle of aspirin to anyone who may wish to discuss certain topics. :devil:

GG

 

[tsv_1]

I consider vibration induced distortion to also be a significant factor in marginal sound.

Me too! I draw the simple analogy of video. Our eyes can quickly/easily tell when a picture is blurred, unfocused, faded, veiled, stretched or in some way suboptimal. The same holds for sound, but it's harder for most of us to immediately recognize these acoustical imperfections. These deleterious effects can arise within the electrical signal (e.g. microphonics, crosstalk, and other noise injection modes into the signal path), and also physically induced, as with speaker chassis movement during playback. Then there's the minor impact of the room's acoustical signature as well

 

[Dan Osib]

Tch, I guess the proper term is "spokes", which connect the magnet with the basket / driver assembly.

Brian, I had read about a 70hz bump in the 116 frequency response and, in my room, it was definitely audible. The lead straps, made and not advertised by Mapleshade, seems to have addressed the issue quite well.

Dan, besides RFI, I consider vibration induced distortion to also be a significant factor in marginal sound.

Bernard, I do offer a bottle of aspirin to anyone who may wish to discuss certain topics. :devil:

GG

So Lead being the type of material it is will also be good for damping vibrations when used inside hifi components. Sounds like a no brainer to me.

 

[Speedskater]

Lead is supposed to completely block out RF INTERFERENCE/RADIO SIGNALS so isn't that a plus for hifi? And it will do this even without it being grounded. Doesn't that sound like a dream come true for us hifi boys?
Now that lots of people are going down the computer audio route using internet streamers etc I bet that LEAD sheets will come in very handy when installed inside our media streamers/computer equipment etc. After all ''RF'' is the biggest killer in this area of hifi.

Well yes lead will block RFI. I started broadcast engineering way back in 1965, while we did use sheet lead in the studio walls for acoustic reasons, we never, never ever used lead for a RFI shield. If you look through industrial magazines, none of the ads for shields are for lead products. Thin copper or aluminum sheets will shield RFI. Most of the RFI enters through the power, interconnect and speaker cables acting as RFI antennas. The other entrances are holes and openings in the chassis. For more reading on the subject, Henry W. Ott has a new 872 page book that you can Google parts of.
http://www.hottconsultants.com/

For sure lead can dampen vibrations (that's what it did in the studio walls) but I don't know how you would mount it effectively in/on a chassis.

 

[Dan Osib]

Well yes lead will block RFI. I started broadcast engineering way back in 1965, while we did use sheet lead in the studio walls for acoustic reasons, we never, never ever used lead for a RFI shield. If you look through industrial magazines, none of the ads for shields are for lead products. Thin copper or aluminum sheets will shield RFI. Most of the RFI enters through the power, interconnect and speaker cables acting as RFI antennas. The other entrances are holes and openings in the chassis. For more reading on the subject, Henry W. Ott has a new 872 page book that you can Google parts of.
http://www.hottconsultants.com/

For sure lead can dampen vibrations (that's what it did in the studio walls) but I don't know how you would mount it effectively in/on a chassis.

You can mount it to the inside walls of a CD Player chassis with a decent off the shelf powerful adhesive glue

 

[Brad225]

Dan I think you would have to try some different products and see. The lead is going to be the one that not everything is going to attach to permanently. The issue will be a thin layer of adhesive so you don't decouple the lead from the cabinet. Some very thin 2 sided tape like carpet tape might do it IF it will stick to the lead.

If all else fails you know black roofing cement and lead flashing have worked together for years.

 

[Brian Walsh]

Brian, I had read about a 70hz bump in the 116 frequency response and, in my room, it was definitely audible. The lead straps, made and not advertised by Mapleshade, seems to have addressed the issue quite well.

OK, but the original post asked about using sheet lead for shielding, not damping vibrations. Two entirely different things. I'm not a fan of lead other than as a compact way of adding mass.