Emu XL-7 & MP-7 User's Group

Mike,

I suggest that you avoid permanently lifting any grounds if 
possible.  That ground prong is always there for a reason.

Although "your mileage may vary", I successfully removed ALL ground-
loop hum from my system using EBtech's Hum Eliminators.  If you are 
not familiar with them, they are essentially a stereo unity gain 
isolation transformer with quarter inch jacks in a rugged steel box.  
About $60 each at Guitar Center.  They are magical, and don't color 
the sound at all.  ...but it won't work for SPDIF I/O.

EBtech also just started offering a smaller and simpler solution, I 
think they call it the "Hum-X", which looks ostensibly like a ground 
lift adapter, but is actually an isolation transformer for the AC 
power side of things.  I haven't used these, so I can't testify.

I guess if you know for a fact that the hum is induced by your laptop 
PS, you might try the Hum-X.  You'll have to look around--they just 
hit the market, I think.  Expect to pay around $40.  Well worth it if 
it solves your problem!

Good luck

Andy




--- In xl7@yahoogroups.com, "Mike-E" <d_jumpmaster@y...> wrote:
> It is a ground loop indeed. The thing causing it is the power 
supply 
> of my laptop. As I also need this supply, maybe I should "ground 
> lift" this device instead of the XL? As a permanent solution?
> Maik
> 
> 
> --- In xl7@yahoogroups.com, erik_magrini@B... wrote:
> > If you're getting a hum in the main audio outs, chances are it's 
a 
> ground 
> > loop.  Other culprit could be power cables laying on your audio 
> cables 
> > (they should always cross at 90 degree angles if they must 
touch).  
> You 
> > can test the ground loop problem by using a "ground lift" plug 
> adaptor 
> > available from pretty much any electronics stores.  IF his fixes 
> the 
> > problem though, DO NOT continue to use it as a solution.  You 
could 
> > potentially cause a lot of problems with your XX_7 by leaving it 
> > ungrounded.  It will at least help you narrow down your trouble 
> shooting. 
> > Plenty of articles online about resoving ground loops, just do a 
> google 
> > search.
> > 
> > rEalm
> > 
> > 
> > 
> > do anyone know how to fix this   (humm)
> > 
> > 2) Connecting analog (main or sub):
> > A humming sound is added to the signal. When I close to software 
> > mixer of the Audiophile the humming stops, but still leaves a lot 
> of 
> > noise en crackles. Totally not acceptable.
> > 
> > Are both problems recognized by anyone? Do the seem to be related?
> > 
> > I also checked the XL-7 on a simple home stereo. It also produces 
> > noise, but it's only noticeable on high volume.
> > 
> > Regards,
> > Maik
> > 
> > 
> > 
> >  
> > 
> > 
> > 
> > 
> > 
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