Line in extreme buzzing noise after connecting guitar

[swell9]

Hello,

Previously my soundcard was performing well, while i recorded some amateur bass lines by connecting my bass into the amplifier and then from the amplifier directly into the computer via line in..
Recently, I did the same thing and i connect my guitar via the line in. But now, i am hearing this loud buzzing noise comnig from the line in signal. And now this continues to happen even if i disconnect my guitar, do a restart, tried opening the case, pulled out the sound card and reinstalled it... but no results?

everything else works fine, i.e. mic in, headphones out, etc..

What could have happened? interference issue? could i have messed up my sound card?

thank you

 

[Petrofsky]

Are you saying that your guitar amp has a line out? How do you know that the buzzing is coming from the line in--does it go away when you mute line in in your computer's mixer? When you say "disconnect my guitar", do you mean unplug the plug from your computer's line in?

 

[swell9]

Hello Pertofsky,
Thanks for the reply
sorry for the late answer though.
No, my guitar does not have a line out. I connected via the headphones out of the guitar into the computer line in.
Yes, the sound goes away when I mute line in, but I can still see the signal level fluctating meaning it is still there.
and by disconnect my guitar yes I do mean unplugging out from line in of the computer.

Any ideas?

 

[Petrofsky]

Yeah, you could have fried something. Line in is, let's see if I have what's-his-name's disease yet, one volt across 600 ohms, as I recall (close enough for jazz). You gave it God knows how many volts. Don't do that. Use some sort of direct input device, instead of your amplifier, between the guitar/bass and the computer. Google on direct input guitar.

 

[outlw6669]

Yup, that is my thought also.
Probably gave the ADC and supporting circuitry quite a jolt.
Pumping an amped signal into the line in (especially with a cheap onboard codec) is really not a good idea.

Sorry for your luck.

 

[outlw6669]

WTH?

Sorry, don't know how this post got here :/

 

[swell9]

Best answer selected by swell9.

 

[swell9]

Thanks again Petrofsky and outlw6669
good information.
Any ideas if the direct input device for guitar would work for bass too?

 

[Petrofsky]

I've never used one. I used to play bass, but that was before PCs, and I let the studio guy do the rest. We miked amps to record. I would expect the cheaper, passive direct input thingies to each have a slightly or not different effect on the sound of either instrument--that one might be better for bass. I'd look for a musician's forum or newsgroup, or search periodicals at the local library.