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Does my laptop need to be grounded when charging?

I generally leave my MacBook Pro attached to its charger while listening to music files played thru my dac via USB.  I have noticed that when I am barefoot and gently rub my finger over the metal surfaces of the laptop that I feel a slight fuzziness as if there is stray voltage going through me.  It is not a shock per se and the sensation goes away when the charger is unplugged.  The charger does not have a ground prong. Should I ground the metal cover of the laptop? Should I get into the habit of disconnecting the charger when I listen to music files from the laptop?  Is this normal?
jc4659
jc4659 OP
551 posts
 
Thank you, Erik.  Yes, my dac already employs "galvanic isolation to the outputs" but not really sure if this means I shouldn't be concerned about noise coming into the dac.  Some of these isolators are inexpensive while others such as the Intona or ISO Regen are >$300.  I am currently using a codex.
jea48
4,432 posts
 
@jc4659
Is the AC plug on the charger polarized? If not try reversing it 180 in the wall outlet and see if that helps.
randy-11
1,913 posts
 
som engineers are thinking that the USB issues are lack of a clock signal wire, and noise on the data wires

noise from a charger might affect the latter, but just try it both ways (blinded) on some very clear passages

or get a DAC or other 'boxes' that can reduce these putative problems... do you have a re-clocker?  (I think the regenerator function in the uptone items may be a reclocker)

AND... a used Apple TV3 costs ~~$40 - can then use Airplay for your Redbook data and beam it over WiFi

jc is giving you a very old and very valuable tip
jc4659 OP
551 posts
 
I tried flipping the polarity on the charger plug and no difference.  I already own a Regen and was considering the ISO Regen upgrade or move to the Intona.  Was hoping other Codex owners would chime in before I spend the additional $$.
jea48
4,432 posts
 
I have noticed that when I am barefoot and gently rub my finger over the metal surfaces of the laptop that I feel a slight fuzziness as if there is stray voltage going through me. It is not a shock per se and the sensation goes away when the charger is unplugged.
I assume the floor is bare concrete or maybe some type of conductive tile. Concrete is conductive. Especially when poured on grade, earth.

I believe what you are experiencing is a very low level electrical shock. Your body may be sensitive to low levels of electrical current passing through it.
Just a guess a difference of potential exists between the laptop and the concrete floor. I would suggest you wear slippers on your feet or some other type of insulator
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