help! noisy tube amps and sound card
Jul 9, 2009 at 3:29 PM Thread Starter Post #1 of 5


Headphoneus Supremus
Sep 17, 2007
i use my audio setup primarily for pc gaming. have had a few ss amps and a few tube amps. the ss amps give me next to no noise, they arent the issue. i have had a ld1 and ld3, still have an ld3. all the same noise-wise. when plugged into my sound card i get noise (staticy buzzing type noise). its not the amp placement -unplugging the cable at the soundcard takes the noise away. i also made a 1/4" chicken wire cage to shield the tubes, that did nothing. unplugging my router did nothing.
i dont want to use a usb dac (i have an xmod and most of the noise went away) because i need my x-fi 3d sound features and eq.
my pc has dual vid cards, 3 fans, x-fi xtrememusic.

is there a way to filter the noise? hopefully without reducing sound quality
Jul 9, 2009 at 3:46 PM Post #2 of 5
It could be bad tubes(tube hiss). It could also be a grounding problem but that's more unlikely as you'll usually hear hum instead of hiss, but try using a mp3 player as its source and see if it improves anything, if not, then bad tubes is probably your next biggest suspect.
Jul 9, 2009 at 4:15 PM Post #3 of 5
its not the tubes. i have several pairs

and the problem is only when plugged into the sound card
Jul 9, 2009 at 6:04 PM Post #4 of 5
So the sound card is in fact transmitting some noise to the tube amp - perhaps it is passing DC, and somehow your SS amps are filtering it. Since all your tube amps are LD, maybe it is something they are prone to. If other sources do not exhibit this issue, then it must be something like this, or a ground loop problem as Moonboy indicated. You can try a cheater plug on the power cable of the LD amp to lift the ground.
Jul 9, 2009 at 8:58 PM Post #5 of 5
Try two things:

1. Try the LD with a cheater plug.

2. Connect a bare wire from the chassis of the LD to the metal on the back of the sound card, or your computer's case.

Try both and report back on the results.

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