Disk noise in audio - Hardware

This is a discussion on Disk noise in audio - Hardware ; I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE. Using the onboard AC97 for sound. and external powered speakers. Sounds are audible in the speakers at low level which sound almost like instability, but which vary with hard ...

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Thread: Disk noise in audio

  1. Disk noise in audio

    I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE. Using the
    onboard AC97 for sound. and external powered speakers.

    Sounds are audible in the speakers at low level which sound almost like
    instability, but which vary with hard disk activity. Muting the sound with
    Kmix stops the noise.

    Can I block these sounds with suppressors, or similar? I don't have any
    ferrite suppressors handy at the moment.

    Doug.

  2. Re: Disk noise in audio

    Doug Laidlaw wrote:
    > I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE. Using the
    > onboard AC97 for sound. and external powered speakers.
    >
    > Sounds are audible in the speakers at low level which sound almost like
    > instability, but which vary with hard disk activity. Muting the sound with
    > Kmix stops the noise.
    >
    > Can I block these sounds with suppressors, or similar? I don't have any
    > ferrite suppressors handy at the moment.


    I have the same problem with one of my laptops, but not the other. I
    don't have that trouble with any of the desktop machines I use. The
    laptop that has the trouble doesn't have Windows on it, or I'd see if it
    was operating system specific.

    I guess I'm not help, other than to say, "me too."

    Sorry....

    --
    PLEASE post a SUMMARY of the answer(s) to your question(s)!
    Show Windows & Gates to the exit door.
    Unless otherwise noted, the statements herein reflect my personal
    opinions and not those of any organization with which I may be affiliated.

  3. Re: Disk noise in audio

    Doug Laidlaw wrote:

    > I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE. Using
    > the onboard AC97 for sound. and external powered speakers.
    >
    > Sounds are audible in the speakers at low level which sound almost like
    > instability, but which vary with hard disk activity.


    Can you redefine "which sound like instability"?

    > Muting the sound with Kmix stops the noise.


    Just a wild guess, not from an IT perspective but from my experience as a
    musician... It is possible that either your speakers or - more likely -
    your soundchip is experiencing microphonics. Concretely, this would boil
    down to your soundchip picking up the vibrations from your hard disk
    activity and amplifying them.

    I myself am mainly an electric guitarist. Real electric guitars make use of
    electromagnetic induction pickups - basically composed of one or two
    bobbins with coil wire, with a magnet inside the bobbin - and can therefore
    only be used with magnetically conductive strings, which pass through the
    top of the pickup's magnetic field - we call this the magnetic window.

    You pluck the string, it starts vibrating in the magnetic field and thus
    disrupts the field, and this causes a signal to be generated in the coil
    wire of the bobbins. As such, electric guitar pickups are not microphones,
    because they can (in theory) only pick up the vibration of a magnetically
    susceptible alloy string in their magnetic window.

    However, on older electric guitars, poorly shielded and loosely assembled
    pickups tend to be microphonic and pick up other sounds as well, such as
    tapping on the guitar's wood or pickguard - this is especially true when
    the pickups are mounted to the pickguard (like on a Fender Stratocaster)
    instead of directly into the wood (with our without a metal or plastic
    mounting ring) as more common with e.g. Gibson, Ibanez, Jackson, et al.

    The microphonic effect is caused by the same principle through which
    piezo-electric pickups on electric-acoustic guitars work and can be
    eliminated by assembling the pickups more firmly, potting them in wax
    and/or mounting them to the guitar body directly instead of to the
    scratchplate.

    My guess is that your soundcard is acting like a piezo-electric pickup,
    which may not be the fault of the chip itself, but rather of the
    motherboard design.

    There are also other factors that could create disturbing sounds, such as
    the EM interference from a rheostat. This is why Gibson invented the
    humbucking pickup in the mid 1950s. Basically and simplified, a humbucker
    pickup consists of two coils, mounted above a single magnet but on opposite
    magnetic poles. These poles are extended to run through the center of the
    bobbins via (usually iron) polepieces to extend the magnetic field so that
    the strings pass through it.

    Both coils are connected in series and 180° out of phase with one another.
    The phase reversal and series connection then eliminates the humming, but
    it would normally also eliminate the actual guitar sound, if it wasn't for
    the fact that having both coils on opposite sides of the magnet's polarity
    also generates a 180° phase reversal, which brings the actual electric
    guitar sound of each coil back in phase with eachother. Humbucking pickups
    do sound "fatter" than single coil pickups because of the series connection
    - a sound that's quite beautiful and warm in its own right, though - but at
    least the hum is canceled.

    > Can I block these sounds with suppressors, or similar? I don't have any
    > ferrite suppressors handy at the moment.


    I think it would be best to make sure your hard disk's vibrations are muted
    sufficiently. There are several mounting brackets and kits available to
    this end, but I have no experience with them myself, and one must of course
    also keep their possible negative effect on heat dissipation into
    account... :-/

    As for the motherboard... There's little you can do about that.
    Motherboards are manufactured to form factor standards which also designate
    the holes for the screws by which you attach the motherboard to the
    chassis, and so my guess is that your motherboard has its sound chip
    located in a less fortunate place where the board is susceptible to
    mechanical vibrations inside the chassis. :-/

    Anyway, just my two cents again... :-/

    --
    *Aragorn*
    (registered GNU/Linux user #223157)

  4. Re: Disk noise in audio

    Doug Laidlaw writes:

    > I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE. Using the
    > onboard AC97 for sound. and external powered speakers.
    >
    > Sounds are audible in the speakers at low level which sound almost like
    > instability, but which vary with hard disk activity. Muting the sound with
    > Kmix stops the noise.
    >
    > Can I block these sounds with suppressors, or similar? I don't have any
    > ferrite suppressors handy at the moment.


    Audio interference from nearby chips is quite common. Using a digital
    (optical or coax) output should get rid of the noise.

    --
    Mns Rullgrd
    mans@mansr.com

  5. Re: Disk noise in audio

    In article ,
    Mns Rullgrd wrote:
    > Doug Laidlaw writes:
    >
    > > I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE. Using the
    > > onboard AC97 for sound. and external powered speakers.
    > >
    > > Sounds are audible in the speakers at low level which sound almost like
    > > instability, but which vary with hard disk activity. Muting the sound with
    > > Kmix stops the noise.
    > >
    > > Can I block these sounds with suppressors, or similar? I don't have any
    > > ferrite suppressors handy at the moment.

    >
    > Audio interference from nearby chips is quite common. Using a digital
    > (optical or coax) output should get rid of the noise.


    Such an option is often not available. AIR, what solved the problem for
    me (or worked around it, one) was hdparm -u "get/set unmaskirq flag
    (0/1)". But it's been years so ICBW. There might be /etc/hdparm.conf
    in your distro but its structure is left as an exercise for the reader.

    --
    -eben QebWenE01R@vTerYizUonI.nOetP http://royalty.mine.nu:81
    AQUARIUS: There's travel in your future when your tongue freezes to the
    back of a speeding bus. Fill the void in your pathetic life by playing
    Whack-a-Mole 17 hours a day. -- Weird Al, _Your Horoscope for Today_

  6. Re: Disk noise in audio

    Hactar wrote:

    > In article ,
    > Måns Rullgård wrote:
    >> Doug Laidlaw writes:
    >>
    >> > I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE.
    >> > Using the onboard AC97 for sound. and external powered speakers.
    >> >
    >> > Sounds are audible in the speakers at low level which sound almost like
    >> > instability, but which vary with hard disk activity. Muting the sound
    >> > with Kmix stops the noise.
    >> >
    >> > Can I block these sounds with suppressors, or similar? I don't have
    >> > any ferrite suppressors handy at the moment.

    >>
    >> Audio interference from nearby chips is quite common. Using a digital
    >> (optical or coax) output should get rid of the noise.

    >
    > Such an option is often not available. AIR, what solved the problem for
    > me (or worked around it, one) was hdparm -u "get/set unmaskirq flag
    > (0/1)". But it's been years so ICBW. There might be /etc/hdparm.conf
    > in your distro but its structure is left as an exercise for the reader.
    >

    Thanks all round. It sounds as though a separate sound card may be the
    answer.

    Doug.

  7. Re: Disk noise in audio

    On Wed, 14 May 2008 17:59:48 +1000, Doug Laidlaw wrote:

    > I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE. Using
    > the onboard AC97 for sound. and external powered speakers.
    >
    > Sounds are audible in the speakers at low level which sound almost like
    > instability, but which vary with hard disk activity. Muting the sound
    > with Kmix stops the noise.
    >
    > Can I block these sounds with suppressors, or similar? I don't have
    > any ferrite suppressors handy at the moment.
    >
    > Doug.


    I had the same problem once. But it was the video that screwed up my
    sound. As the screen changed, the hum would also change. I discovered
    on opening my box that when I moved my sound card over one slot away from
    the video card, the sound stopped. So maybe you should open up your box
    and see if any wires from your hard-drive are close to the sound card.

    stonerfish

  8. Re: Disk noise in audio

    Aragorn wrote:
    > Just a wild guess, not from an IT perspective but from my
    > experience as a musician... It is possible that either your
    > speakers or - more likely - your soundchip is experiencing
    > microphonics. Concretely, this would boil down to your
    > soundchip picking up the vibrations from your hard disk
    > activity and amplifying them.
    >
    > I myself am mainly an electric guitarist. Real electric
    > guitars make use of electromagnetic induction pickups -
    > basically composed of one or two bobbins with coil wire, with a
    > magnet inside the bobbin - and can therefore only be used with
    > magnetically conductive strings, which pass through the top of
    > the pickup's magnetic field - we call this the magnetic window.
    >
    > You pluck the string, it starts vibrating in the magnetic
    > field and thus disrupts the field, and this causes a signal
    > to be generated in the coil wire of the bobbins. As such,
    > electric guitar pickups are not microphones, because they
    > can (in theory) only pick up the vibration of a magnetically
    > susceptible alloy string in their magnetic window.


    Hiya,

    Your description of the coil/pickup stuff seems pretty good.
    But, it's quite unlikely that there is magnetic interference
    affecting the internals of the sound chip itself. I speak as
    a designer of chips. Also, there are regulations as to how
    much electromagnetic interference is tolerable to be put out by
    electronic equipment. It's *much* more likely that the disk
    drive is demanding different amounts of power from the power
    supply and that this is causing the power supply voltage to
    rattle a little, which could be picked up by the circuitry on
    the soundcard. It's still possible that the gain on an unused
    channel is turned way up, and that the channel is picking up
    electric field interference from whatever is running inside the
    case of the computer. But, I think magnetic field interference
    is pretty unlikely.

    Cheers....


    --
    PLEASE post a SUMMARY of the answer(s) to your question(s)!
    Show Windows & Gates to the exit door.
    Unless otherwise noted, the statements herein reflect my personal
    opinions and not those of any organization with which I may be affiliated.

  9. Re: Disk noise in audio

    Doug Laidlaw writes:

    < I am running a Gigabyte motherboard with Mandriva 2008.1 and KDE. Using the
    < onboard AC97 for sound. and external powered speakers.
    >

    < Sounds are audible in the speakers at low level which sound almost like
    < instability, but which vary with hard disk activity. Muting the sound with
    < Kmix stops the noise.
    >

    < Can I block these sounds with suppressors, or similar? I don't have any
    < ferrite suppressors handy at the moment.
    >

    < Doug.


    Check your mic inputs and plug them with a 6-32 stainless steal screw and 30
    feet of enameled copper 30awg hooked up to a nine volt.

    Just kidding. They do sell dead plugs and I would recommend one of them, but
    some people like the feedback.

    `hdparm -M' will allow you to adjust the acoustic settings of a `ide' hard
    drive if the drive allows it. It is actually recommended for certain drives.
    Also slowing down the CPU cycles if an option in your bios may help. If you
    can slow down your disk drive - some will some won't.

    I placed two sata drives on a cardboard box while makeing a quick backup
    through vista and they made some loud ass noise. I thought I was tapping
    morse code with a hammer (I suffer from paranoia).

    Cardboard usually works. Place in between video card and rest of pci bus. It
    gets hot so be careful. Removing excess fans and grounding the power
    supply/chassis might work. Be careful removing fans from the CPU! If you got
    that funky paste it may start ok, but I dunno how well your machine reacts
    to overheating. It should shut down immediately.

    Place the computer on cardboard.

    Use cardboard for mounting the drives externally.

    I actually chased out a funky sound with a variable speed fan several times.
    I think that the excess noise was result of heat build up in the case. The
    pc speaker may have added some feedback do to thermo-reactions. The fan may
    have cooled her off a bit or just smoothed the current. Dunno. Plugging one
    in while the machine was on worked. Mystery fan method #1.

    I am not a professional. I just make lots of mistakes. Staying clear of the
    ac line can help too and making sure you have air flowing from the power
    supply with plenty of space. May mean dusting.



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