18 Apr
2003
18 Apr
'03
5:08 p.m.
Hi,
I have a new Dell laptop with a headphone jack as the only external
audio output. With headphones, the sound quality is good and there is
little noise to be heard. However, if I plug in my monitors, the
output crackles and hums, regardless of the mixer levels. There is
217 hz constant hum, a 125 hz hum when moving windows, and a 689 hz
whine when I run Pd. The output crackles when I move the mouse
(external USB). I just noticed that it goes away when I unplug the AC
adaptor. I think I remember a similar problem coming up on this list
before, but I had no luck searching the archives. How can I solve
this?
Thanks,
Ben
20 Apr
20 Apr
6:57 p.m.
Ben Saylor wrote:
Hi,
I have a new Dell laptop with a headphone jack as the only external
audio output. With headphones, the sound quality is good and there is
little noise to be heard. However, if I plug in my monitors, the
output crackles and hums, regardless of the mixer levels. There is
I bought an Edirol UA-1A USB DAC.
http://www.edirol.com/
21 Apr
21 Apr
6:13 a.m.
Dear friends ,
i have also problem with hum when i used sound with my laptop, it's the
plug, when i used only battery, it's perfect... but when i put directly
electricity... it's finish, i have a big hum and it's terrible when you
make sound or playing live... but i think it's an hardware problem not
software. But is someone find a solution (without the fact to buy an
external card) as for example find another AC adaptater...??? Mylaptop
is Gericom and i use Mandrake 9.0... if you've got an idea, your just
welcoming... and thanks you.
best
juto
7:39 a.m.
yes,
same here. it is very common for laptops to have terrible ground loop
problems when connected to other equipment, which is what you are
hearing. the two solutions i can think of:
a ) use a DI box between your laptop audio output and everything else to
lift the signal off ground--an expensive option if you are just using
the headphone out, of course!
or
b ) find another way to remove your laptop from ground. using batteries
is one, but then your processor slips into a lower mode and you lose
some of that computing power you paid for. a friend suggested using a
powerstrip that either has no ground or has had its ground removed.
haven't tried it yet, but that sounds like the best bet. better than
hacking the grounds off your AC adaptor, at least... :-)
best,
derek
juto aviten wrote:
Dear friends ,
i have also problem with hum when i used sound with my laptop, it's
the plug, when i used only battery, it's perfect... but when i put
directly electricity... it's finish, i have a big hum and it's
terrible when you make sound or playing live... but i think it's an
hardware problem not software. But is someone find a solution (without
the fact to buy an external card) as for example find another AC
adaptater...??? Mylaptop is Gericom and i use Mandrake 9.0... if
you've got an idea, your just welcoming... and thanks you.
best
juto
8:37 a.m.
derek holzer wrote:
yes,
same here. it is very common for laptops to have terrible ground loop
problems when connected to other equipment, which is what you are
hearing. the two solutions i can think of:
a ) use a DI box between your laptop audio output and everything else
to lift the signal off ground--an expensive option if you are just
using the headphone out, of course!
or
b ) find another way to remove your laptop from ground. using
batteries is one, but then your processor slips into a lower mode and
you lose some of that computing power you paid for. a friend suggested
using a powerstrip that either has no ground or has had its ground
removed. haven't tried it yet, but that sounds like the best bet.
better than hacking the grounds off your AC adaptor, at least... :-)
Thanks Derek,
i will try some of this solutions
best
juto
22 Apr
22 Apr
8:01 a.m.
Hallo,
derek holzer hat gesagt: // derek holzer wrote:
yes,
same here. it is very common for laptops to have terrible ground loop
problems when connected to other equipment, which is what you are
hearing. the two solutions i can think of:
a ) use a DI box between your laptop audio output and everything else to
lift the signal off ground--an expensive option if you are just using
the headphone out, of course!
You can also use the Monacor FGA-40 filter, which lifts ground, has
two cinch connectors on either side and costs just 17.20 EUR. It is
available in car audio shops or online for example here:
http://www.power-discounter.de/p3721.html
(Germany)
or
b ) find another way to remove your laptop from ground. using batteries
is one, but then your processor slips into a lower mode and you lose
some of that computing power you paid for. a friend suggested using a
powerstrip that either has no ground or has had its ground removed.
haven't tried it yet, but that sounds like the best bet.
Well, epanorama calls this solution the "cheater plug" and doesn't
recommend it:
http://www.epanorama.net/documents/groundloop/problem_solving.html
better than hacking the grounds off your AC adaptor,
at least... :-)
The result is the same as the ground-less plug and thus might be
dangerous, as well.
ciao
--
Frank Barknecht _ ______footils.org__
12:44 p.m.
On Tue, Apr 22, 2003 at 11:51:42AM +0200, Frank Barknecht wrote:
You can also use the Monacor FGA-40 filter, which
lifts ground, has
two cinch connectors on either side and costs just 17.20 EUR. It is
available in car audio shops or online for example here:
http://www.power-discounter.de/p3721.html
(Germany)
do you have one? How's it sound?
--
Paul Winkler
http://www.slinkp.com
Look! Up in the sky! It's SHINY FORNICATOR!
(random hero from isometric.spaceninja.com)
1:09 p.m.
Hallo,
Paul Winkler hat gesagt: // Paul Winkler wrote:
On Tue, Apr 22, 2003 at 11:51:42AM +0200, Frank
Barknecht wrote:
No, I don't have one, as disconnecting some stuff from my amp resolved
the problem.
ciao
--
Frank Barknecht _ ______footils.org__
You can also use the Monacor FGA-40 filter, which
lifts ground, has
do you have one? How's it sound?
7738
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linux-audio-user@lists.linuxaudio.org
7 comments
6 participants
participants (6)
-
Ben Saylor -
derek holzer -
Frank Barknecht -
juto aviten -
Paul Winkler -
Tim