cmoy and mint shielding.

[jonnywolfet]

is it possible to shield an amp against inteference from other sources?
both my cmoy and mint pick up hard discs spinning and other annoying interference, like cell phone signals.
is there an easy way to shield against this? doesnt need to be 100% effective, but it would be nice...

 

[[AK]Zip]

Are you using a metal / aluminum case? If not then I highly suggest it.

-Alex-

 

[jonnywolfet]

i read somewhere that layers of tin foil and paper do well at shielding, is there any truth in this?

otherwise i shall have to investigate a metal case.

 

[Heady]

If the amp is inside a metal tin or casing, then it is already shielded. The problem is in the cables, the interconnects and phones cables. They do pick up RF especially cell phones if placed near the cables.

 

[jonnywolfet]

what if its not in a metal case? plastic cases are much smaller and lighter (plus i have a few...). do you thing its worth doing the tin foil thing?

 

[thedoctor]

Quote:

Originally Posted by jonnywolfet what if its not in a metal case? plastic cases are much smaller and lighter (plus i have a few...). do you thing its worth doing the tin foil thing?

personally i don't think it's worth it. i mean the shielding thingy. i've used both plastic casings and metal casings for my amps and they sound more or less the same. RF interference usually occurs at the cables rather than the amp.
if you're only building a simple portable amp (read: CMOY), then i don't think proper shielding should mean much. but some might argue with this. but hey, if it's a Millet or M3 or PPA then maybe you could wanna get the best possible sound from it.

shielding a small case might be a hard thing to do compared to a bigger non-portable desk-amp type of cases.

 

[Heady]

Quote:

Originally Posted by jonnywolfet what if its not in a metal case? plastic cases are much smaller and lighter (plus i have a few...). do you thing its worth doing the tin foil thing?

The good doctor has already answered your question. However, let me share that I listen with my CD and MP3 player running beside my notebook computer. I have never had problems with my CMOY (metal tin) or Pimeta (plastic enclosure). The only time was when I placed my cell phone near the interconnect and it gave me a good fright when a call came in.

A friend who had problems with RF, used a shielded cable to wire up the sockets to and from the PCB and it solved his problem. So, it is the cables and not the amp itself which seems to be vulnerable.

 

[jonnywolfet]

my experience is when i bind the amp to my hd5 for portable use, it picks up inteference from the hd5. this happens with both amps, in all 3 of my hdd mp3 players.

if i hold them apart, i get no annoying inteference.