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Re: Home Studio



just adding a quick note to all this advice:

the other day I sourced an ugly digital whine noise in my rack to one of 
the
cables. I spent a week suspecting and checking every piece of gear, 
changing
the order of stuff, playing with isolation, even opening a few things and
looking for any mysterious shorts, with no result. Finally discovered that
switching one cable from left channel to right channel caused the noise to
follow.....swapped out the cable and the noise was gone. 

The problem? I measured the cable with an ohmmeter, 10 ohms across the
ground from one end to the other!!! This usually means either the shield is
damaged or there is a problem in the connector itself. In my case it was 
the
connector. Letting my EE background kick in: impedance across the ground
meant my audio signal to the power amp was not choosing that nice short 
path
for its ground, and instead took some long circular path to find a ground
path between the one output and the power amp input. This created a big
current loop, acting as an antennae and picking up the horrible noise from
some other piece of gear that was normally silent.

the moral: use good quality cables, with good, secure shielding. Doesn't
need to be some exotic alloy for $300/ft. Just good quality and save
yourself a lot of trouble.  And take care of them....cables that have been
stepped on for years, wrapped up a thousand times, yanked around.......the
shields will get pretty frayed. Replace 'em! That can definitely affect
things like system noise. It can even affect the sound, if a large
resistance in a ground/signal wire and the natural capacitance of the wire
form a filter in the audio range, you can hear it.

kim
________________________________________________________
Kim Flint, MTS                 408-752-9284
Chromatic Research             kflint@chromatic.com
http://www.chromatic.com