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Hello!
A background (about 50hz) rumble appears in a sound from microphone.
Windows XP SP2.
I tried two headsets (which surely are good). The rumble decreases if
I touch the computer case. I checked the inside of the case, did not
find any improper contacts. The sound card is Creative sound blaster
live ct4830. I tried the latest Microsoft and Creative drivers. The
Creative driver does not output sound from microphone to speakers at
the same time, but only from a recording from the microphone. How to
prevent the rumble?
Best regards,
Dima

"D" wrote ...
> A background (about 50hz) rumble appears in a sound from
> microphone. Windows XP SP2.

In common use, "rumble" applies to low frequency *random noise*
such as from an air duct or a subway train or from a distant highway.

If you are hearing interference from your power mains (presumably
50Hz if you are posting from Russia), that is called "hum" and it is a
very *constant* tone.

We will assume that you mean that you are hearing interference
from power-line hum. If it is *rumble*, then it is acoustic and you
should be able to hear it with your ears, no headset, no computer.

> I tried two headsets (which surely are good). The rumble decreases if
> I touch the computer case. I checked the inside of the case, did not
> find any improper contacts. The sound card is Creative sound blaster
> live ct4830. I tried the latest Microsoft and Creative drivers. The
> Creative driver does not output sound from microphone to speakers at
> the same time, but only from a recording from the microphone. How to
> prevent the rumble?

Does it hum when no headset is plugged in?
If so, then there is a problem with the computer or sound card.
If no, then *both* of your headsets have a problem

Does the hum change when you move the headset around
the room?

Does it hum when you try using a differen computer mic?

rcrowley posting from rec.audio.pro

On Mon, 15 Oct 2007 13:34:04 -0700, D <> wrote:

>Hello!
>A background (about 50hz) rumble appears in a sound from microphone.
>Windows XP SP2.
>I tried two headsets (which surely are good). The rumble decreases if
>I touch the computer case. I checked the inside of the case, did not
>find any improper contacts. The sound card is Creative sound blaster
>live ct4830. I tried the latest Microsoft and Creative drivers. The
>Creative driver does not output sound from microphone to speakers at
>the same time, but only from a recording from the microphone. How to
>prevent the rumble?


Is "rumble" a precise term or are we chasing a mains hum?

D <> wrote in
news: oups.com:

> Hello!
> A background (about 50hz) rumble appears in a sound from
> microphone. Windows XP SP2.
> I tried two headsets (which surely are good). The rumble
> decreases if I touch the computer case.

IMO, this undoubtedly means you have a ground problem. As if
"about 50 Hz" was not enough of a tipoff. It's always 50 or 60.

But it MAY just be a totally crappy microphone. Try another one,
preferably a good one.

If it's NOT the microphone, I am not a technician so I can't
tell you how to fix it, but first thing you should do is check
that everything to do with you system is plugged into the SAME
AC circuit, preferably same outlet with power bar(s), and then
you can buy or borrow (or steal I suppose) a little gizmo which
you plug into the wall outlet and it tells you if everything's
OK. Other than that, ask a technician.

> I checked the
> inside of the case, did not find any improper contacts. The
> sound card is Creative sound blaster live ct4830. I tried
> the latest Microsoft and Creative drivers. The Creative
> driver does not output sound from microphone to speakers at
> the same time, but only from a recording from the
> microphone.

That si impossible. Check your mixer volumes, mutes etc.
Watch out for feedback, it can be VERY unpleasant, but no sound
card manufacturer will disable mic to speakers direct just
because of that.

> How to prevent the rumble?
> Best regards,
> Dima




--
Waiting for the day when it is illegal to use anything but Vista
on any computer in the world.

D wrote:
> Hello!
> A background (about 50hz) rumble appears in a sound from microphone.
> Windows XP SP2.
> I tried two headsets (which surely are good). The rumble decreases
> if I touch the computer case. I checked the inside of the case, did
> not find any improper contacts. The sound card is Creative sound
> blaster live ct4830. I tried the latest Microsoft and Creative
> drivers. The Creative driver does not output sound from microphone
> to speakers at the same time, but only from a recording from the
> microphone. How to prevent the rumble?
> Best regards,
> Dima

What are you recording, I know you state form a microphone, but are
you plugging in something else into the microphone socket? If so that
would be the problem try plugging it into the line in socket.

If it is a microphone then make sure that it is being fully pushed
home, if it is then try another one (they aren't exactly expesinve).

Others have mentioned ground loops etc, but try the easy bit (normally
the cheapest bits) first.

As a matter of fact I get a continual low level 50hz hum from my line
in post unless I actually plug something into it then it dissapears,
so you could also try turning off all ports you are not using before
doing your recording.

On Oct 16, 1:45 am, "Richard Crowley" <rcrow...@xp7rt.net> wrote:
> "D" wrote ...
>
> > A background (about 50hz) rumble appears in a sound from
> > microphone. Windows XP SP2.
>
> In common use, "rumble" applies to low frequency *random noise*
> such as from an air duct or a subway train or from a distant highway.
>
> If you are hearing interference from your power mains (presumably
> 50Hz if you are posting from Russia), that is called "hum" and it is a
> very *constant* tone.
>
> We will assume that you mean that you are hearing interference
> from power-line hum. If it is *rumble*, then it is acoustic and you
> should be able to hear it with your ears, no headset, no computer.
>
> > I tried two headsets (which surely are good). The rumble decreases if
> > I touch the computer case. I checked the inside of the case, did not
> > find any improper contacts. The sound card is Creative sound blaster
> > live ct4830. I tried the latest Microsoft and Creative drivers. The
> > Creative driver does not output sound from microphone to speakers at
> > the same time, but only from a recording from the microphone. How to
> > prevent the rumble?
>
> Does it hum when no headset is plugged in?
> If so, then there is a problem with the computer or sound card.
> If no, then *both* of your headsets have a problem
>
> Does the hum change when you move the headset around
> the room?
>
> Does it hum when you try using a differen computer mic?
>
> rcrowley posting from rec.audio.pro
Thanks Richard Crowley for your explanations!
It does not hum when no headset is plugged in.
One of the headsets is brand new and checked.
Yes, the hum changes when I move the headset around the room: the
further from the computer case the louder.
Yes, it hums when I try using a differen computer mic: both headsets.

On Oct 16, 3:34 am, Laurence Payne <NOSPAMlpayne1ATdsl.pipex.com>
wrote:
> On Mon, 15 Oct 2007 13:34:04 -0700, D <t...@bk.ru> wrote:
> >Hello!
> >A background (about 50hz) rumble appears in a sound from microphone.
> >Windows XP SP2.
> >I tried two headsets (which surely are good). The rumble decreases if
> >I touch the computer case. I checked the inside of the case, did not
> >find any improper contacts. The sound card is Creative sound blaster
> >live ct4830. I tried the latest Microsoft and Creative drivers. The
> >Creative driver does not output sound from microphone to speakers at
> >the same time, but only from a recording from the microphone. How to
> >prevent the rumble?
>
> Is "rumble" a precise term or are we chasing a mains hum?
Yes, we are chasing a mains hum.

On Oct 16, 11:08 am, thanatoid <wait...@the.exit.invalid> wrote:
> D <t...@bk.ru> wrote innews: groups.com:
>
> > Hello!
> > A background (about 50hz) rumble appears in a sound from
> > microphone. Windows XP SP2.
> > I tried two headsets (which surely are good). The rumble
> > decreases if I touch the computer case.
>
> IMO, this undoubtedly means you have a ground problem. As if
> "about 50 Hz" was not enough of a tipoff. It's always 50 or 60.
>
> But it MAY just be a totally crappy microphone. Try another one,
> preferably a good one.
>
> If it's NOT the microphone, I am not a technician so I can't
> tell you how to fix it, but first thing you should do is check
> that everything to do with you system is plugged into the SAME
> AC circuit, preferably same outlet with power bar(s), and then
> you can buy or borrow (or steal I suppose) a little gizmo which
> you plug into the wall outlet and it tells you if everything's
> OK. Other than that, ask a technician.
>
> > I checked the
> > inside of the case, did not find any improper contacts. The
> > sound card is Creative sound blaster live ct4830. I tried
> > the latest Microsoft and Creative drivers. The Creative
> > driver does not output sound from microphone to speakers at
> > the same time, but only from a recording from the
> > microphone.
>
> That si impossible. Check your mixer volumes, mutes etc.
> Watch out for feedback, it can be VERY unpleasant, but no sound
> card manufacturer will disable mic to speakers direct just
> because of that.
>
> > How to prevent the rumble?
> > Best regards,
> > Dima
>
> --
> Waiting for the day when it is illegal to use anything but Vista
> on any computer in the world.
Thanks thanatoid for your suggestions!
I checked my mixer volumes, mutes etc. and did not find anything
wrong. I uninstalled the Creative driver.

On Oct 16, 2:06 pm, "kráftéé" <kraftee@b&e-cottee.me.uk> wrote:
> D wrote:
> > Hello!
> > A background (about 50hz) rumble appears in a sound from microphone.
> > Windows XP SP2.
> > I tried two headsets (which surely are good). The rumble decreases
> > if I touch the computer case. I checked the inside of the case, did
> > not find any improper contacts. The sound card is Creative sound
> > blaster live ct4830. I tried the latest Microsoft and Creative
> > drivers. The Creative driver does not output sound from microphone
> > to speakers at the same time, but only from a recording from the
> > microphone. How to prevent the rumble?
> > Best regards,
> > Dima
>
> What are you recording, I know you state form a microphone, but are
> you plugging in something else into the microphone socket? If so that
> would be the problem try plugging it into the line in socket.
>
> If it is a microphone then make sure that it is being fully pushed
> home, if it is then try another one (they aren't exactly expesinve).
>
> Others have mentioned ground loops etc, but try the easy bit (normally
> the cheapest bits) first.
>
> As a matter of fact I get a continual low level 50hz hum from my line
> in post unless I actually plug something into it then it dissapears,
> so you could also try turning off all ports you are not using before
> doing your recording.
Thanks kráftéé for your suggestions!
I checked with brand new headset - the same.

"D" wrote ...
> It does not hum when no headset is plugged in.

Then you can eliminate any problem with the computer,
the sound card, or any software including drivers, etc.

> One of the headsets is brand new and checked.

What does "checked" mean? Do either of the headsets work
OK on another computer?

> Yes, the hum changes when I move the headset around the room: the
> further from the computer case the louder.

I would take a wild guess that it has a shielding or grounding problem.

> Yes, it hums when I try using a differen computer mic: both headsets.

The problem may be with the basic design if both headsets
show the same symptoms.