Author Topic: Shielding a D6 with paint?  (Read 1074 times)

Offline funkylaundry

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Shielding a D6 with paint?
« on: April 18, 2016, 08:43:17 AM »
So I have a Clavinet D6 and I've tried all kinds of measures to reduce the hum induced when used alongside other electronic equipment:

- I mounted the preamp in an aluminum housing.
- I added extra grounding points.
- I applied (and grounded) copper tape to the housing itself of the pickups.

I do have the aluminum shield under the bottom pickup, but especially the hum induced by having it on top of another keyboard is terrible, so I thought thought about different possible fixes:

- Mount an additional aluminum plate (I already have the stock aluminum shielding plate) under the instrument itself. To net screw up the alignment of the keys I thought about simply mounting it to the outside of the instrument.
- Try to build an aluminum enclosure around the pickups. Du to the nature of the instrument there would be a lot of leaks, though.

So I just tried googling about what kind of metals would be most efficient for insulating and stumbled on something interesting: EMF Paint. Apparently this stuff was designed by the military to contain radio signals within a command central, but is now being sold to consumers and coorporations who may either wish to protect their private networks or insulate their bedrooms against electro magnetic pollution.

I watched a few youtube videos and the effects seem impressive. Did anyone try something like this to shield a Clavinet?
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Offline OZDOC

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Re: Shielding a D6 with paint?
« Reply #1 on: April 18, 2016, 07:13:15 PM »
Shielding paint has been around for many decades. It is a liquid solution of conductive particles. It suits applications where there are complex shapes to cover such as the insides of plastic moulded parts. It still requires the enclosure to be continuous to work. So, given all the things you've tried this is not going to make any difference and it'll just make a mess of a good Clavinet.

Are you sure that you're not getting magnetic field interference (possibly from a transformer) from the keyboard you're sitting the Clav near or on?
How about fixing the keyboard that you're sitting the Clav on? A shielded transformer or a toroid replacement.

The ultimate test is to get a piece of mild steel sheet the size of the keyboard below and place it between the bottom keyboard and the Clav.
If that makes no difference then shielding paint is unlikely to.
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Offline The Real MC

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Re: Shielding a D6 with paint?
« Reply #2 on: April 18, 2016, 08:55:56 PM »
If the conductive paint flakes, you will have loose pieces of basically metal pieces inside the Clav which can short circuit something.  I'd be very reluctant with this solution.

Offline OZDOC

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Re: Shielding a D6 with paint?
« Reply #3 on: April 18, 2016, 09:43:44 PM »
Just to be clear, the oscillating magnetic field from a transformer will pass straight through aluminium and any paint based coating. The methods you've been trying are really only suited to radiated electrical noise.
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